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112582

3701662

Note on the Relative Chemical Intensities of Direct Sunlight and Diffuse Daylight at Different Altitudes of the Sun

20

24

Proceedings of the Royal Society of London

Henry E. Roscoe|Joseph Baxendell

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0012

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112582

10.1098/rspl.1866.0012

http://www.jstor.org/stable/112582

Optics

Astronomy

Optics

II . " Note on the relative Chemlical Intensities of direct Sunlight and diffuse Daylight at different altitudes of the Sun . " i3By HENRY E. RoscoE , F.R.S. , and JOSEPH BAXXENDELL , F.R.A.S. rIeceived February 8 , 1866 . The method of determining the chemical intensity of daylight described by one of us* presents a convenient means of experimentally comparing the intensity of the chemically active rays which reach the earth 's horizontal surface directly from the sun with that of the same rays reflected from the atmosphere and constituting diffuse daylight . For this purpose it is only necessary alternately to expose pieces of the standard sensitive paper , according to the method described in the memoir above mentioned , to the action of the total light of day , and to the diffuse daylight alone , which is easily done by cutting off the sun 's direct rays from the sensitive paper , by throwing upon the paper a shadow cast by a small screen , having an apparent diameter slightly greater than that of the solar disk . In the first case the chemical intensity of the total daylight , in the second that of the diffuse light is determined ; the difference between these two observations giving the chemical intensity of the direct sunlight . As the experiments which we have already made in this direction have led us to conclusions differing altogether from those derived from theoretical considerations concerning the relative chemical intensities of direct and diffuse sunlight , we think that , although this investigation is incomplete , the results are worthy of the attention of the Society . No direct photometrical determinations of the relative intensity of sun and diffuse light have up to this time been made ; but Clausius tl has calculated this relation for varying altitudes of the sun , founding his calculations upon the hypothesis ( generally adopted by meteorologists to explain the red tints of the morning and evening sk ) that the diffused light is reflected , not from the par ' J3akerian Lecture , 1865 . Phil. Trans. 1865 , p. 605 . t Poggendorff ' , i 'Annalen , ' dcl . lxxii . p. 291 . tides of air or solid floating material , but from the minute vesicles of water which are supposed to be always contained in large quantities in the atmosphere . According to this hypothesis , Clausius obtained the following numbers as expressing the intensities of direct sunlight and diffused daylight for altitudes varying from 200 to 60:-Calculated Intensities of Sun 's Altitudes . Total Daylight . Diffuse Light . Direct Sunlight . 200 0-10049 0-06736 0003313 25 ? 0-17808 0'09291 0'08517 30 ? 0-25933 0-11184 0-14749 350 0-34049 0-12654 0-21395 40 ? 0-41957 0-13832 0-28125 i500 0-56686 0-15599 0-41087 160o 0-69442 0-16822 0-52620 ( The intensity of sunlight at an altitude of 90 ? , unweakened by atmospheric absorption , is taken as the unit . ) The measurement of the relative chemical intensities were made at three localities : ( 1 ) Owens College , Manchester , 530 29 ' N. , and 01 9M O W. ; ( 2 ) the Observatory , Cheetham HIill , near Manchester ; and ( 3 ) the summit of the Kinigstuhl , near I-eidelberg , 1900 feet above the sea , in 490 24 ' N. , and 34m 48 " E. We are indebted for the latter observations to Dr. Wolkoff , who kindly forwarded us his results through Professor Bunsen . The following experimental numbers , obtained at Owens College , may serve to illustrate the method adopted ; in most cases several ( four or five ) observations of the inltensities of the total and diffuse light were made quickly one after the other , and the mean of all the readings taken . TABLE I.-Observations at Owens College , Manchester , 530 29 ' N. 011 9"1 0s W. G reenwich Sun 's uns Number Intensity Number Intensity Sun 's Sun 's Intenslity . Da . Mean Time Altiof total of of of of atof Observa Obsel vadifoused Observadirect Angle . tude . Daylight . onsa tion . Ansle . tule . DayLight . tions . Sunlight . 1865 . hm0 Oct. 6 . 12 00 44W . 31 17 073 3 -068 4 -005 7 . 9 30 36 42 E. 23 23 '060 1 -056 1 -004 12 00 48W . 30 54 -063 1 -057 1 -006 18 . 11 25 7 18E . 26 30 -075 2 -056 2 -001 11 45 2 17 E. 26 46.111 2 -089 2 -022 12 30 8 58 W. 26 20 -088 4 '087 4 '001 1 19 21 13 W. 24 15 '071 4 -067 5 -004 2 45 42 43 W. 17 8 -062 2 -053 2 -009 24 . 0 45 12 51W7 . 23 42 -139 3 -113 5 026 1 20 21 41W . 22 4 -123 5 '115 4 -008 Nov.15 12 01 33W . 17 55 -101 5 -082 4 '019 12 40 11 33W . 17 15 -065 4 '063 5 '002 1 15 20 18 W. 15 50 -063 4 '058 5 -005 21 . 12 10 3 43 W. 16 27 -056 5 -055 4 '001 12 30 8 43 W. 16 8 -066 4.058 5 '008 12 45 12 28W . 15 44 '058 4 -050 5 '008 ... ... . As the altitudes here observed vary only from 15 ' 44 ' to 31 ? ? 47 ' , we thought it best to collect the results into two groups , containing the eight highest and eight lowest observed altitudes . TABLE II.-Results of Observations at Owens College . Number of Intensity nten Observations . Altitnde , of Sky or of tie atio of diffused Sun to Sky . of Sun . Sunlight . Sun to Sky Sky . Sun . ofS Daylight . Group 1 33 34 17 ? ? 8 ' -066 -007 0-106 2 20 24 26 38 '074 -008 0-108 The determinations made at Cheetham Hill ( 53 ? ? 30 ' 50 " N. , and Oh 8m 56s W. ) were sixty-three in number , in which the altitude varies from 1 6 ? ? 8 ' to 4 6 ? ? 14 ' , and these are divided into three groups , as follows : TABLE III.-Results of Observations at Cheetham Hill . Number of Intensity Observations . MeAen of Sky or Insty Ratio of Alfitude diffused Sunlight . Sun to Sky . of Sun . Sunlig_h . Sky . Sun . ofSun . Daylight Group 1 23 24 19 ? ? 30 ' '064 -012 0-187 2 22 22 25 31 -091 -019 0 208 3 18 17 34 8 -104 -026 0-250 The range of altitude in the Heidelberg experiments being a much wider one ( viz. from 0 ? to 63 ? ? 49 ' ) , we have been able to arrange these ( containing ninety-nine observations ) in five groups , as follows : TABLE IV.-Results of Observations at Heidelberg . Number of Range of Mean Intensity Intensity ao ObservaAltitude of Altitude of kyor of direct RatS o fS tions . of Sun . of Sun . dffu Sunlight . Daylight . Group 1 10 0 ? to 15 ? ? 7 ? ? 15 ' '048 -002 0-041 2 19 15 -30 24 43 -134 -066 0-472 3 31 30 -45 34 34 -170 -136 0'800 4 22 45 -60 53 37 -174 -263 1 511 5 17 above 60 62 30 '199 -319 1-603 The curves on P1 . I. fig. 1 are derived from the foregoing numbers , the ordinates representing the intensities and the abscissme denoting the corresponding altitudes . The curves marked a , b , c give respectively the observations at Heidelberg , Cheetham Hill , and Owens College ; the dotted curves represent the intensities of the diffuse light , the black curves those of the direct sunlight . The ratio of the sun and skylight for the same places is represented by the curves a , 6 , and c , fig. 2 . In the following Table the experimental ratios are compared with those calculated by Clausius . TABLFE V.-Ratio of Chemical Intensities of direct Sunlight to diffuse Light , Experiments . Sun 's Calculated --Altitude . ( Clausius ) . Heidelberg . Cheetham Hill . Owens College . 20 ? 0-491 0-350 0'19 0'10 25 0-896 0-480 0-20 0'11 30 1-320 0-650 0-23 35 1-690 0-820 0-26 40 2-032 1 00 50 2-634 1-37 60 3-129 1-60 These numbers show that whilst at 20 ? of altitude , according to theory , the relation of the intensities of diffuse light to direct sunlight is as 100 to 49'1 , the experiments at Heidelberg give a relation of 100 to 35 ; those at Cheetham Hill 100 to 19 , and those in Manchester 100 to 10 . If we compare the theoretical ratio for higher altitudes , we find that in our latitudes the ratio even at 35 ? of altitude is only as 100 for diffuse light to 26 for sunlight , whereas theory gives the relation as 100 to 169 . The Heidelberg observations show indeed a more rapid rise in the intensity of the direct sun 's rays , the ratio reaching 100 to 82 for 35 ? of altitude . The great difference between these and the other experimental results must doubtless be ascribed to the considerable elevation ( 1900 feet above the sea ) at which these observations were made . Even at Heidelberg , however , no less than eight observations show that at low elevations the chemical action of the sun becomes altogether inappreciable , whilst that of the diffuse light is still considerable ; and the same inactive condition of direct sunlight at low altitudes has been frequently observed both at Owens College and Cheetham Hill . In these cases the intensity of the sun 's direct visual rays was considerable , and a strong shadow was cast ; but the more highly refrangible rays were altogether absent , and the ratio became infinite . Heidelberg Observations . Altitude . Direct Sun . Diffuse Light . 0 ? ? 34 ' 0000 0-026 1 32 0'000 0-024 2 29 0'000 0-038 3 27 0'000 0-028 60 0'000 0-030 10 40 0'000 0'083 11 51 0'000 0-079 12 58 0'000 0'080 In some of the experiments made at Cheetham Hill the shadow of a small disk was thrown on a horizontal surface of white paper , and careful estimations made of the relative brightness of the shaded and unshaded portions of the surface . A comparison of these results with those obtained at the same time for the chemical rays showed that with the sun at a mean altitude of 25 ? ? 16 ' , the mean ratio of the chemical intensities of direct and diffused light being 0'23 , that of the luminous intensities was 4'00 , or that the action of the atmosphere was 17'4 times greater on the chemically active than on the luminous rays of sunlight . A series of photometrical experiments made afterwards at Owens College gave the following results Mean altitude of the sun ... ... ... . 12 ? ? 3 ' Mean ratio of chemical intensity ... . 0'053 Mean ratio of luminous intensity ... . 1 400 It appears therefore that with the sun at an altitude of 12 ? ? 3 ' , the action of the atmosphere was 26'4 greater on the chemical than on the luminous rays . The foregoing experiments appear to proveI . That the effect of the atmosphere upon the highly refrangible and chemically active solar rays is regulated by totally different laws from those founded upon the hypothesis of the reflexion by means of hollow vesicles of water . II . That the ratio of the chemical intensity of direct to diffuse sunlight for a given altitude of the sun at different localities is not constant , varying with the transparency , &c. , of the atmosphere . III . That this ratio of " chemical " intensity does not in the least correspond to the ratio of " visible " intensity as estimated by the eye ; the action of the atmosphere being 17'4 times greater upon the chemical than on the luminous rays when the sun 's altitude is about 25 ? ? 16 ' , and 26'4 times greater when the sun 's altitude is 12 ? ? 3 ' . _-oc:f ? : . ' & i Vo . a P._ . _/ RATIO OF DIRECT TO DIFFUSED LIGHT AT DIFFERENT ALTITUDES OF THE SUN . / / : / -~~~~ I ... ... ' I_ _ ... ... ... ... ... ... ... ... . . : 11 CbeetkF , aaIfi.-liAL. . fvl7.ia ' ( > ie , . : CHEMICAL INTENSiYV OF DIFFUSED AND DIRECT SUN-LIGHT ' AT DIFFERENT ALTITUDES OF THE SUN . -~--------A-------~--L -I-1I -j~~ k:a ... ..oo ' -8io -Io 17_jO 3^ wnj_ ? L_.0 _. . -^0 2l < ? 0 * 3\0 ? . ^ < 90~~~~1 / 1190( I ' / 7 ? L ... 400._ . * : 04 . | . O00-'QO & 0:00L L. i4t L6c < 67 : a. _H1a ; d.ede & a 6'y , :'- , ia..9,9 o & -e , az,.a ' . il b ' . ? .e ? .wka [ .t 11:iaat-a/ vni . ohs'vrV ' 'o:t/ . a , ' ... ... ... . . & ... ... oa'ae..y___ ? ? 9 ... ... ... --. . | ' ... . " .a^^^JSI/ .r^ssi . 4^ " A & iFi . II I~ . , f , , ; i ' I| I_ -_OP_O~ ... ... ... ... ... ... . . ! _~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ iIiII -----i i " ' ? '---=- ? -"'T-r ? . ? C^"-'U'P r 7j ; i1 It iIi --i L ~__ . _~..___._f_i._ ; _.i . _ ,

112583

3701662

Researches on Acids of the Lactic Series.--No. I. Synthesis of Acids of the Lactic Series. [Abstract]

25

28

Proceedings of the Royal Society of London

E. Frankland|B. F. Duppa

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112583

http://www.jstor.org/stable/112583

Chemistry 2

Biochemistry

Chemistry

" Researches on Acids of the Lactic Series.-No . I. Synthesis of Acids of the Lactic Series . " By E. FRANKLAND , F.R.S. , and B. F. DUPPA , Esq. Received February 14 , 1866 . i(Abstract . ) In the first part of this paper the authors give the details of the synthetical production of numerous acids of the lactic family , which have been briefly described in a series of notes already published in these Proceedings during the years 1863 , 1864 , and 1865 . In the concluding portion of the present paper , they discuss the theoretical considerations which arise out of these investigations . They call attention to the existence of a group of elements , to which they give the name oxalyl and the formula ( C O Ho ) , and which exists not only in all acids of the lactic series , but also in nearly every known organic acid . The isolated molecule of this radical is oxalic acid , { COHo C0 Ho , in proof of which they show that when oxalic ether is acted upon by nascent amyl , it is converted into caproic ether : f C0Eto CBuH22 CB IIT2 COEto+ { CBuH=2 CCOEto . Oxalic ether . Amyl . Caproic ether . Oxalyl is closely related to cyanogen , the two radicals passing into each other in a host of reactions ; hence the production of cyanides from the ammonium-salts of the fatty acids on the one hand , and the synthesis of acids from certain cyanogen compounds on the other , -a reaction first pointed out by Kolbe and Frankland* , and which has of late yielded such important results in the hands of Maxwell Simpsont and of Kolbe and of Hugo MiillerT . C N " C0 Hol . 1CN C N " COHo . Cyanogen . Oxalyl . The researches of these chemists prove that the introduction of cyanogen into an organic compound , and its subsequenit transformation into oxalyl , converts that compound into an acid , or , if already an acid , increases its basicity by unity ( for each atom of oxalyl so developed ) , this result being apparently quite independent of the position of the oxalyl in the molecule . The atom of oxalyl ( as the above molecular formula shows ) may be regarded as methyl ( C H3 ) , in which two atoms of hydrogen have been replaced by one of oxygen , and the third by hydroxyl ( Ho ) . It may be objected that the group of elements , which is thus invested with radical functions , lacks one of the fundamental characteristics of a radical by its proneness to change ; but this characteristic is exhibited by the commonly received radicals in a very varied degree . And even methyl itself , which certainly possesses it in the most marked manner , readily permits of its hydrogen being replaced by chlorine or bromine on the one hand , and by sodium on the other . All compound radicals , the authors remark , are purely conventional groupings of elements intended to simplify the expression of chemical change ; and in this respect they believe the group oxalyl , entering as it does into the constitution of nearly every organic acid , has as valid a claim to a distinct name as the most universally recognized radical . Its admission renders possible the following very simple expression of the law governing the basicity of nearly all organic acids-an organic acid containing n atoms of oxalyl is n basic . The authors classify all acids of the lactic series at present known , or which could be obtained by obvious processes , into the following eight divisions : General formula . C R111 lo 1 . Normal acids ... ... ... ... ... ... . . C0 Ho 2 . Etheric normal acids ... ... ... ... C HR . C0 Ho 3 . Secondary acids ... ... ... ... ... O T2Io OH , Ho 4 . Etheric secondary acids ... ... ... . . C Ho Gf C:lRHo CR11 Ho 5 . Normal olefine acids ... ... ... ... . . ( C H2g ) C0 Ho + qCR IHRo 6 . Etheric normal olefine acids ... ... . . ( C H2 ) , n COHo +f CR2Ho 7 . Secondary olefine acids ... ... ... . . ( C COHo C0 BRo 8 . Etheric secondary olefine acids ... ... ( C H2)n CO Ho. A normal acid of the lactic series may be defined as one in which an atom of carbon is united with oxalyl , hydroxyl , and at least one atom of hydrogen . In the above general formula for these acids R may be either hydrogen , or any alcohol hydrogen . An etheric normal acid is constituted like a normal acid , but contains a monatomic organic radical , chlorous or basylous , in the place of the hydrogen of the hydroxyl . A secondary acid is one in which an atom of carbon is united with oxalyl , hydroxyl , and two atoms of an alcohol radical . An etheric secondary acid stands in the same relation to a secondary , as an etheric normal does to a normal acid . A normal olefine acid is one in which the atom of carbon united with oxalyl is not united with hydroxyl , and in which the atom of carbon united with hydroxyl is combined with not less than one atom of hydrogen . In -1this formula R may be either hydrogen or a monatomic alcohol radical , and the olefine , or diatomic radical of these acids , may belong to either the ethylene , or the ethylidene series . An etheric normal olefine acid differs from a normal olefine acid only in D having the hydrogen of the hydroxyl replaced by an organic radical positive or negative . A secondary olefine acid is one in which the atom of carbon united with oxalyl is not combined with hydroxyl , and in which the atom of carbon united with hydroxyl is also combined with two monatomic alcohol radicals . In the above formula R must be a monatomic alcohol radical . An etheric secondary olefine acid is related to the secondary olefine acids in the same way as the etheric normal olefine acids are related to the normal olefine acids . The numerous cases of isomerism in the lactic series are next examined and explained ; and the authors then show how the radicals which are employed for the production of the synthesized acids may again be separated , thus affording analytical as well as synthetical proof of the constitution of these acids . These investigations have conducted the authors to the following conclusions:1 . All acids of the lactic series are essentially monobasic . 2 . These acids are of four species , viz. normal , secondary , normal olefine , and secondary olefine acids ; and each of these species has its own etheric series of acids , in which the hydrogen of the hydroxyl contained in the positive or basylous constituent of the acid is replaced by a compound organic radical , either positive or negative . 3 . The normal acids are derived from oxalic acid by the replacement of one atom of oxygen , either by two atoms of hydrogen , or by one atom of hydrogen and one atom of an alcohol radical . 4 . The secondary acids are derived from oxalic acid by the replacement of one atom of oxygen by two atoms of monatomic alcohol radicals . V , 5 The olefine acids are derived from oxalic acid by a like substitution of two monatomic positive radicals for one atom of oxygen , with the addition of a diatomic radical ( C. IT2f ) between the two atoms of oxalyl . 6 . The acids of the lactic series stand in the very simple relation to the acids of the acetic series first pointed out by Kolbe , viz. that by the replacement , by hydrogen , of the hydroxyl , ethoxyl , &c. contained ill the positive radical of an acid of the lactic series , that acid becomes converted into a member of the acetic series . 7 . The acids of the lactic series stand in an almost equally simple relation to those of the acrylic series , as is seen on comparing the two following formula:{ C ( C HI ) H Ho C ( C 112 ) IH . CO Ho CO Ho. Lactic acid . Acrylic acid .

112584

3701662

Note on a Correspondence between Her Majesty's Government and the President and Council of the Royal Society regarding Meteorological Observations to Be Made by Sea and Land

29

38

Proceedings of the Royal Society of London

Lieutenant-General Sabine

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0014

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112584

10.1098/rspl.1866.0014

http://www.jstor.org/stable/112584

Biography

Meteorology

Biography

I. " Note on a Correspondence between Her Majesty 's Government and the President and Council of the Royal Society regarding Meteorological Observations to be made by Sea and Land . " By Lieutenant-General SABINE , P.R.S. Received March 8 , 1866 . Her Majesty 's Government having been pleased to consult the Royal Society on several occasions in the last few years regarding the proper steps to be taken by this country , under the sanction and authority of its Government , for the prosecution , in cooperation with the Governments of other States in Europe and America , of systematically conducted meteorological observations by Land and Sea , it may be desirable to offer to the Fellows a resume of the correspondence , and of the suggestions which from time to time have been tendered on the part of the Society to the several depart . ments of the State . The correspondence commenced by a communication from the Foreign Office in March 1852 , transmitting , by direction of the Earl of Malmesbury , several documents received from foreign governments in reply to a proposition which had been made to them by Her Majesty 's Government , for their cooperation in establishing a uniform system of recording meteorological observations ; and requesting the opinion of the President and Council of the Royal Society in reference to these documents , and more especially in reference to a communication from the Government of the United States of America respecting the manner in which the proposed cooperation might be carried out . The reply of the President and Council was dated May 10 , 1852 . It recognized fully the importance of well-directed and systematically conducted meteorological observations , not only for their scientific value , but also on account of the important bearing which correct climatological knowledge has on the welfare and material interests of the people of every country . With reference to a specific proposal for the adoption , by all countries , of a uniform plan in respect to instruments and modes of observation in meteorological researches on land , the President and Council expressed a doubt whether any practical advantage was likely to be gained by pressing such a recommendation in the then state of meteorological science . Many of the principal Governments of the European Continent had already organized systematic climatological researches throughout their respective States under the superintendence of men eminently qualified by theoretical and practical knowledge , and whose previous publications had obtained for them a general European reputation . The instruments employed in each country had.been constructed under the care of the Superintendents , and the instructions for their use drawn up and published by them ; the observations were also received by them and reduced and coordinated , and were in this state published periodically by the respective governments . To call on countries so advanced in systematically conducted meteorological observations to remodel their instructions and instruments with the view of establishing uniformity in these respects , was scarcely likely to be successful , especially if the request proceeded from a country which " had no similarly organized system extending over its own area . Moreover the discussions which had taken place at the Magnetical and Meteorological Congress assembled at the Cambridge Meeting of the British Association in 1845 , which was attended by the Superintendents of the different continental systems , had manifested so marked a disposition on the part of the meteorologists of the different countries to adhere to their respective arrangements in regard to instruments , times of observation , and modes of publication , as to produce a strong conviction that the suitable time for pressing a proposal for the substitution of a uniform scheme , however advantageous in some respects , had not then arrived . But in respect to Marine Meteorology the case was widely different ; and the suggestions which the President and Council felt it their duty to offer on that subject had a much more positive character , and were directed to immediate action . An application had been made by the Government of the United States to that of our own country to give a greater extension and a more systematic direction to meteorological observations made at sea . Apart from the important scientific bearing of such researches , the wellknown publications of Lieutenant Maury had given to the Government of the United States a fair claim to make such an application to that of our own country , to whose commercial interests a practical knowledge of the meteorological statistics of the ocean was not less important than to those of the United States . Accordingly , in their reply to the Foreign Office , the President and Council did not fail to express emphatically their hope that the application for cooperation , thus earnestly addressed by the Government of the United States , might not be addressed in vain . The following extracts from a memoir addressed by Lieutenant Maury to the Secretary of the United States Navy , printed in " Papers presented to the House of Lords by command of Her Majesty , pursuant to an address dated Februairy 21 , 1853 , " will show that the sugglestions thts made by the President and Council , both in regard to Land and to Sea Meteorological Observations , were fully concurred in by Lieutenant Maury , on his return from an official mission to visit and report upon the meteorological establishments of the principal States of Europe . Lieutenant Maury 's memoir is dated November 6 , 1852 . " I would recommend that the United States should abandon , for the present at least , that part of the 'Universal System ' which relates to the Land , and that we should direct our efforts mainly to the Sea , where there is such a rich harvest to be gathered for navigation and commerce ... . I am induced to make this recommendation in consequence of the evident reluctance with which Russia , Austria , Bavaria , Belgium , and other powers seem to regard any change in their systems of meteorological observations on shore ... . Each country seems to have adopted a system of its own , according to which its labourers have been accustomed to work , and to which its meteorologists are more or less partial . Any proposition having in view for these systems a change so radical as to bring them to uniformity , and reduce them to one for all the world , would , I have reason to believe , be regarded with more or less jealousy by many ... . . Not so , however , with regard to the Sea ; that proposal meets with decided favour and warmest support . " Lieutenant Maury then quotes largely from the Report of the President and Council of the Royal Society ( already referred to ) , and from the anniversary address of the President of the British Association at the Belfast Meeting in 1852 , in illustration of the advantages which navigation and commerce may derive from the extension of maritime researches by the proposed cooperation of Great Britaii and the United States . In June 1854 the Board of Trade informed the President and Council by letter that they were about to submit to Panliament an estimate for an office for the discussion of observations on Meteorology to be made at Sea in all parts of the globe , in conformity with the reconmmendation of a conference held at Brussels in the preceding year ; and that it was their intention to publish from time to time , and to circulate , such statistical results , obtained by means of the observations referred to , as might be considered most desirable by men versed in the science of meteorology , in addition to such other information as might be required for the purposes of navigation . To this end , the Board of Trade were desirous of obtaining the opinion of the Royal Society as to what were the great desiderata in that science , and as to the forms which may be best calculated to exhibit the great atmospheric laws which it may be most desirable to develope . The Board further stated that , " as it may possibly happen that observations on land upon an extended scale may hereafter be made and discussed in the same office , it is desirable that the reply of the Royal Society should keep in view and provide for such a contingency . " In their reply to this communication , dated February 22 , 1855 , the President and Council kept carefully in view the relative importance which the Board of Trade attached to the suggestions which might be olrered respecting observations to be made at sea , and observations to be made on land ; the immediate bearing of the one , and the contingent and eventual bearing of the other . Their reply consequently bore chiefly on points to be investigated by marine observations , -under the several heads of barometric variations ; of those of the dry air and of aqueous vapour ; of the mean temperature of the air ; of the temperature of the sea , and investigations regarding currents ; of storms and gales ; thunderstorms ; auroras and falling stars ; and charts of the magnetic variation . ( Proc. Roy . Soc. , vol. vii . pp. 342-361 . ) These were treated of in their generality , as subjects of investigation to be made ( in the words of the Board of Trade ) " at sea in ail parts of the globe . " Nor was the contingency of observations to be made on land upon an extended scale , " which may hereafter be made and discussed in the same office , " overlooked ; and to enable the Royal Society to be more fully prepared , and to be ready " to provide for the contingency " whenever it should present itself , the President and Council put themselves in communication with several of their foreign members who were known as distinguished cultivators of meteorological science , -having always in view the possibility that , when the occasion should occur , they might be prepared to offer such suggestions as might facilitate the purpose which had been deemed so desirable by Her Majesty 's Government in the preceding year . The chief difficulty which had then presented itself had been the desire shown by the meteorologists of the different European States to adhere to the instruments , and more particularly to the hours of observation , to which they had been accustomed . The hours had been selected partly on grounds of convenience , and partly in the belief that they were those best suited to receive the corrections required in different localities for diurnal and casual variations . The most hopeful way of surmounting the difficulties in question would obviously be the introduction of instruments which should be continuously self-recording ; such instruments would in addition supply the exact instants of the maxima and minima of the different phenomena-points greatly required in the discussion of the laws of extensive atmospherical disturbances . At the epoch of the Cambridge Congress in 1845 it was understood that no perfectly reliable instruments for continuous record were in use amongst the continental observers . The self-recording instruments of M. Kreil , employed at the observatories of Prague , Senftenberg , Vienna , and Munich , and which had also been in use for many months at the Kew Observatory , were not continuously self-recording , and were also , in the opinion of many , not altogether free from objections . The construction of instruments both in magnetism and meteorology which should serve this important purpose and at the same time be free froma causes of error in other ways , had been a cherished object of the Committee of the Kew Observatory from the commencement of that institution . The advance which had been accomplished at a very early period may perhaps best be stated in the following extract from the fourth report of Mr. Ronalds , its Director , published in the volume of the British Association for 1847 , Trans. of Sections , page 30 . " The preliminary experiments on the photographic registration of the atmospheric electrometer , the thermometer , the barometer , and the declination-magnet having been long since completed and published , and their results having warranted the cost and trouble of constructing apparatus of a durable and convenient character , a declination-magnet and a barometer have been mounted at Kew which scrupulously fulfil the requisite conditions without the intervention of those friction-rollers , levers , pivots , or other mechanism which have hitherto rendered self-registering apparatus so objectionable . " Mr. Ronalds added that it was his " intention to provide during the ensuing year complete apparatus on like principles for registering as many of the other meteorological and magnetical instruments as funds will permit . " The instruments which would be required for a complete equipment of a meteorological observatory would be those which should automatically and continuously record ( 1 ) the variations of the atmospheric pressure ; ( 2 ) those of the dry and wet thermometers ; ( 3 ) those of the force and direction of the wind ; and ( 4 ) those of the atmospheric electricity . Of these , Nos. 1 and 2 , as has been already said , had been devised at Kew in or before 1847 . Dr. Robinson 's hemispherical-cup anemometer , of which a description was published in 1851 in the Transactions of the Royal Irish Academy , and which was immediately adopted at Kew , records , in a manner which I believe is universally held to be unexceptionable , the direction and force of the wind at every instant . The electrometer to which Mr. Ronalds referred in his report of 1847 , though highly ingenious and yielding very instructive results , was not continuously self-recording . An electrometer fulfilling this condition was consequently a desideratum until Professor William Thomson devised , and caused to be constructed under his own superintendence at Kew , in the spring of 1861 , the self-recording electrometer which has been subsequently in successful work at that observatory ; thus supplying the fourth apparatus required for a complete meteorological record . It may be added that the Kew Barograph photographs its records self-compensated for temperature ; its curves consequently are in immediate readiness for the lithographer or engraver . Such was the state of instrumental preparation at the Kew Observatory when the untimely death of Admiral FitzRoy , who had been placed by the Board of Trade in charge of the meteorological office established in 1855 , occasioned a renewal of the communications which had taken place on the formation of the office , between the Board of Trade and the Royal Society . In a letter dated May 26 , 1865 , the Board of Trade recalled to the recollection of the Royal Society the recommendations regarding marine meteorology contained in the letter of the President and Council of February 22 , 1855 , stating that those recommendations had been adopted by the Board as the basis of the proceedings of the meteorological department ; and that in conformity therewith instruments and logs had been prepared and furnished to ships proceeding on distant voyages , and had been returned to the office ; and that some progress had been made in carrying into effect the original programme of tabulating these in readiness for statistical charts . It was further stated that " in 1859 or 1860 , the French Government having adopted a system of telegraphing and publishing the actual state of the weather from one place to another , in which Admiral FitzRoy 's cooperation had been sanctioned , a considerable part of the vote previously applied to obtaining and digesting observations was devoted to these telegrams ; and further , that in 1861 , Admiral FitzRoy having grafted on this system of telegraphic communication a system of forecasting the weather , and , on occasions of anticipated storms , the giving of special warnings , communicated by telegraph to the different ports and there made known by hoisting certain signals , the whole or almost the whole of the funds originally voted for the purpose of observations had thus been diverted from their original scientific purpose to an object deemed more immediately practical . " The decease of Admiral FitzRoy afforded , in the judgment of the Board of Trade , a fitting opportunity to review the past proceedings and present state of the meteorological department , and rendered them desirous of again consulting the Royal Society on the constitution and objects of the department , and the mode in which those objects might be most effectually attained . The points on which the opinion of the Royal Society was specially requested were the following:1 . Are the points specified in the letter of the Royal Society of the 22nd of February 1855 still deemed as important for the interests of science and navigation as they were then considered ? ? 2 . To what extent have any of these objects been answered by what has already been done by the meteorological department ? ? 3 . What steps should be talen for making use of the observations already collected ? ? 4 . Is it desirable to make any , and what , further observations on any of the subjects mentioned in the Iloyal Society 's letter of the 22ndl of February 1855 ? ? 5 . What is the nature of the basis on which the system of daily forecasts and storm-warnings established by Admiral Fitz oy rests ? Are they founded on scientific principles , so that they , or any part of them , may be carried on satisfactorily notwithstanding Admiral Fitzloy 's ( lecease ? ? 6 . Can the Royal Society suggest any improvemenit in the form and manner of the process pursued in forecasts and storm-warnings ? ? 7 . Have the lRoyal Society any er general suggestions to make as to the mode , place , 'or establishment in , at , or by which the duties of the meteorological department ct an be be performed ? it being understoodLta tha the Admiiralty are willing to undertake to place in the hands of the iHydrrographer all those observations which can properly be used in framing charts for the purposes of navigation , but not those which relate to meteorology proper or meteorological observations on land . Several documents accompanied this communication , -amongst them a statement by Mr. Babington , chief clerk in Admiral FitzRoy 's office , regarding the method adopted in the department in regard to forecasts and stormwarnings ; and returns , exhibiting a comparison of the probable force of the wind indicated by signals in the years ending March 31 , 1864 , and March 31 , 1865 , and its actual state as reported in the three days following the exhibition of the signals . The reply of the President and Council was dated June 15 , 1865 . It suggested the continuance , for the present , of the practice of forecasts and storm-warnings as before , and the continued issue of instructions and forms to such masters of vessels proceeding on distant voyages as might be expected to make a profitable use of them ; both these duties to be continued under Mr. Babington 's superintendence , by whom in effect they had been carried on for some time previous to Admiral FitzRoy 's decease . And it was further recommended that both the system under which the forecasts and storm-warnings had been hitherto carried on , and the extent and value of the information regarding ocean-statistics which had been accumulated in the office of the Board of Trade , should be subjected to a careful examination . These recommendations were adopted ; and a Committee has been appointed , of three members , one nominated by the Board of Trade , a second by the Admiralty , and a third by the Royal Society , to report on what has been done , and to suggest any modifications which may appear desirable for the future . The report of this Committee is expected to appear very shortly . With reference to the subject of Land Meteorology , the President and Council had been apprised by the Board of Trade , in February 1855 , that " observations on land upon an extended scale might hereafter be made and discussed in the meteorological department of the Board , " and had been requested to be " prepared for such a contingency . " In the more recent correspondence in 1865 , the subject of land observations was again brought forward , and the Royal Society was invited to offer suggestions in reference to it . Thus appealed to , the President and Council would have failed in their duty if they had not replied fully and explicitly to a request proceeding from Her Majesty 's Government , -carefully restricting themselves , in their reply , to such suggestions as their own knowledge enabled them to affirm with confidence could be carried into practical operation , and which at the same time enabled them to respond to the more general inquiry in the letter from the Board of the 26th of May 1865 , viz. " Have the Royal Society any suggestions to make as to the mode , place , or establishment in , at , or by which the duties of the meteorological department can best be performed ? " The reply of the President and Council was as follows:- " There remain , therefore , to be noticed solely the considerations which relate to 'Meteorology roper , ' i. e. to the Land Meteorology of the British Islands . We find that the principal states of the European Continent have almost without exception formed establishments for the collection and publication periodically of the meteorology of their respective countries . The arrangements consist usually of a central office , at which instruments and instructions are provided for a number of stations , greater or less , according to the area which they represent ; at which stations observations are made and transmitted to the central office , where the results of all are reduced , coor . dinated , and published . The small extent of the area comprised by the British Islands in comparison with the territories of many of the European States may requirefewer stations ; but in a matter now so generally attended to and provided for , it seems scarcely fitting that our country should be behind others . There is , moreover , a peculiarity in the meteorological position of the British Islands in respect to Europe generally as its northwestern outpost , in consequence of which an especial duty appears to devolve upon us . M. Matteucci , in a very recent publication , has already made the important remark that extensive atmospheric disturbances which first invade Ireland and England are those which , in winter more especially , extend to and pass the Alps ( although somewhat retarded by them ) , and spread over Italy ; and that storms so telegraphed from England have actually reached Italy , and have been found to correspond with the accounts subsequently received from Italian 3Mediterranean Ports . " A few stations-say six , distributed at nearly equal distances in a meridional direction from the south of England to the north of Scotland , furnished with self-recording instruments supplied from and duly verified at one of the stations regarded as a central station , and exhibiting a continuous record of the temperature , pressure , electric and hygrometric state of the atmosphere , and of the force and direction of the wind-might perhaps be sufficient to supply authoritative knowledge of those peculiarities in the meteorology of our country which would be viewed as of the most importance to other countries , and would at the same time form authentic points of reference for the use of our own meteorologists . The scientific progress of meteorology from this time forward requires indeed such continuous records-first , for the sake of the knowledge which they alone can effectively supply , and , next , for comparison with the results of independent observation not continuous . The actual photograms or other mechanical representations , transmitted weekly by post to the central station , would constitute a lithographed page for each day in the year , comprehending the phenomena at all the six stations , each separate curve admitting of exact measurement from its own base-line , the precise value of which might in every case be specified . " The President and Council suggest that the observatory of the British Association at Kew might with much propriety and public advantage be adopted as the central meteorological station . " It has been already shown , in the earlier part of this communication , that the Kew Observatory possesses all the instruments required in a complete system of continuous self-recording meteorological observation . These are well known to the Directors of many meteorological observatories both at home and abroad , who in several instances , after personal examination , have applied for and obtained for their own establishments similar instruments prepared under the Superintendent of the Kew Observatory , Mr. Balfour Stewart . Thus , Barographs on the Kew pattern have been supplied to Oxford , St. Petersburgh , and Coimbra ; Anemometers to St. Petersburgh , Odessa , Melbourne , Coimbra , Ascension , Madras , Agra , and two meteorological stations established by Admiral FitzRoy ; Electrographs to Lisbon and Coimbra . There would be no difficulty ( as was stated in the letter to the Board of Trade ) in preparing instruments at Kew for affiliated meteorological stations in Britain , and in arranging for their verification and comparison with the Kew standards , as well as in giving to those in whose hands they may be placed such instructions as may ensure uniformity of operation . Such functions constitute in fact part of the original purposes of the Institution at Kew , and are in continual exercise both for magnetism and for meteorology . It is not unreasonable to anticipate that the success of such a system of continuous self-recording meteorological observation , exemplified over the limited area of the British Islands , might occasion its wider extension , and thus contribute to the virtual fulfilment of the desire expressed by Her Majesty 's Government in 1852 " for the adoption of a general and uniform plan of making and recording meteorological observations . " POSTSCRIPT , March 23.-Since this " Note " 'was communicated to the Royal Society , I have read with great satisfaction the opinion expressed in the following extract from the " Report of a Committee assembled at the Board of Trade to consider certain questions relating to the Meteorological Department of the Board , " pages 52 , 53:"There is no doubt that self-recording instruments are urgently needed in the present state of meteorological science , and that they will soon in all probability be largely employed both in this country and abroad . Their advantages are manifest . By reason of the continuity of their records , no wave or variation of any description in any of the meteorological elements can escape notice , and the course of that wave or variation can be tracked with certainty from station to station , and its modification at the time of reaching each station in succession can be accordingly observed . For the same reason one difficulty , now seriously felt , in charting the weather , viz. that which arises from observers in different places and countries adopting different hours of observation , would wholly disappear ; and a further difficulty , viz. that which arises from observers being unpunctual to their professed hours of observation , would disappear also . The unvarying accuracy of the record is an advantage of still greater importance than might be expected by those who have had no experience of the frequent errors to be found in meteorological registers . Each error creates considerable confusion ; it throws doubt on the observations accurately made at neighbouring places ; and that doubt cannot be removed except by the continuity of the records at those places . This continuity is unattainable unless the weather happens to be uniform over a wide district , or unless observations are made at many more places than would be needed , if reliance could be placed upon the accuracy of the observers . Another advantage of self-recording instruments is that their records are independent of particular scales . Their notation is in lines and curves that can be measured with equal facility according to any desired scale . The thermometer lines could be measured at pleasure according to Fahrenheit 's scale , as used in England ; to the Centigrade , as in France ; or to Reaumur 's , as in Germany . The barometer lines could be measured with equal ease in English inches , in millimetres , or in Paris feet . For the various reasons we have mentioned , self-recording instruments are of eminent local and international utility . The establishment of a series of them in England would confer a wide benefit . They would give precision and fulness to the charts of our own weather ; they would set an example that foreign governments would soon follow ; and they would afford material in a very acceptable form to meteorologists at home and abroad for the discussion of the weather of Europe at large . "

112585

3701662

On the Action of Compasses in Iron Ships

38

42

Proceedings of the Royal Society of London

John Lilley

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6.0.4

http://dx.doi.org/10.1098/rspl.1866.0015

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112585

10.1098/rspl.1866.0015

http://www.jstor.org/stable/112585

Biography

Measurement

Biography

II . " On the Action of Compasses in Iron Ships.9 By Mr. JOHN LILLEY . Communicated by Sir W. SNOW HARRIs , F.R.S. Received February 9 , 1866 . Although many ably-written papers upon this subject have at various times appeared , none of them seem to be of that simple practical character as to supersede the necessity of any further investigation of the subject , or deter the author from submitting to the Royal Society the results of many years ' practical experience in the construction of the mariner 's compass , and its adjustment in iron ships . These results are given with a view to advance our knowledge of this important and great practical scientific question , and to add still more to the security of life and property . In the present day , when iron shipbuilding is so widely extending , it is presumed that the most humble offering tending to place the directive action of the compass beyond the reach of disturbing magnetic forces may not be unacceptable . It is unnecessary here to enter into a mathematical investigation of the properties or magnetic condition of iron ships , this part of the subject having been already fully treated and developed by many learned men . The author rather proposes to confine himself to the consideration of the probable causes of the disasters so frequently attendant on the navigation of iron and other ships , through defective compass guidance ; such disasters , according to the author 's experience , may be traced , in a large majority of cases , to one or other of the following causes:38 [ March 8 , 1 . The improper construction and position of the steering binnacle and compass . 2 . The too frequent habit of placing all reliance upon the steering binnacle compass . 3 . Allowing the compasses to be too long in use without due examiniation . 4 . The improper manner in which the compasses have been adjusted . 1 . The construction of the compass is at all times a matter of great importance , but when applied to the case of an iron ship its value is increased tenfold ; it is most essential that the compass should be of the best attainable ( lescription , and so constructed that its centre and pivot should be subject to the smallest possible amount of friction in order that the needles may be entirely free to follow the directive force of the earth , and have at the same time great retentive power . Some years since the author observed , when adjusting an iron steamer 's coinpass furnished by him with very powerful needles , discarded from some previous experiments in magnetism , and which were only 4 inches in length , that more than usually satisfactory results were obtained ; the deviations were of a smaller value , and far more uniform than when using needles of greater length . IHe has since adopted the practice of employing needles not exceeding 6 inches in length , even for cards of the largest diameter . The position of the compass is also important ; it is an objectionable practice of too frequent occurrence , even with the ordinary plane spindle and barrel , to place the binnacle near the steering-wheel ; with the screw apparatus , arms , and levers the practice becomes extremely dangerous , the whole mass , from the process of manufacture , being found highly magnetic . The idea , however , prevails that all this is a matter of indifference , since the counteracting magnets are supposed to neutralize all magnetic disturbance . The reverse , however , is the case ; many instances have come under the author 's notice practically in which errors have arisen solely from this cause , but which ceased to exist on the removal of the binnacle to a distance of 4 feet from the spindle , or twice the original distance . It would be far better , in all cases , if the steering-wheel could be placed before the mizzenmast of ships , instead of abaft and close to the stern , as is generally the case ; compasses would invariably act better and be subject to smaller changes . 2 . It is too frequently the practice to place exclusive reliance upon the steering-compass ; this may be attended with less trouble to the navigator , but is , as regards the safety of the ship , very perilous . As ships are now fitted , the steering-compass is placed very near the stern ; and since in iron ships the magnetic forces are generally concentrated at the two ends of the vessel , it must be obvious that it is placed at that spot where the greatest variations may be expected . Every iron ship should be furnished with a properly constructed standard binnacle not less than 5 feet high above the deck , suitably placed , and containing a compass fitted in the most con venient manner for taking observations without the aid of compensating magnets . By this compass alone should the ship be navigated ; the steering-compass is simply the helmsman 's guide . Many iron ships have been fitted with two navigating binnacles , the one for steering , and the other at the fore part of the poop , both furnished with compensating magnets , and obviously both subject to the same changes incident to the change of hemisphere ; cases of ships thus fitted have come under the author 's notice , in which many providential escapes from wreck have occurred on the return passage from India ; in one particular instance , land was made on the coast of Ireland when the commander imagined he was entering the channel , an error that could not have arisen had the ship been furnished with an uncompensated standard compass instead of a compensated compass . In the uncompensated compass , the changes of deviation are far less than would be found in a compensated compass placed not more than 2 feet above iron beams . Very full directions on this subject will be found in the valuable work of the late Capt. E. J. Johnson , R.N. , and it is much to be regretted that this work is not more studied by commanders and officers of iron ships . 3 . Frequent disasters have been found to occur in consequence of allowing the compass to be too long in use without due examination , more particularly in steam-vessels going short voyages ; the author is led to this conclusion from the fact of having readjusted iron vessels ' compasses stated to be largely in error , but subsequently found , on swinging the ship , to have a comparatively small error , the supposed error being referable to a defective centre and pivot in the compass itself , which prevented the needle from reaching its meridional position . In such cases an error of 8 ? or 10 ? has been often observed ; the importance of such an error in narrow channels is too obvious to require comment . There are valuable and simple appliances which to a very great extent remove this difficulty , and which are comparatively inexpensive ; it is to be much regretted that a great indifference to the state of vessels ' compasses exists in the minds of those under whose care the compasses are often placed , and who , it might be expected , would from experience have been more sensitively alive to the absolute necessity of keeping the compasses , as far as possible , in a state of efficiency . If a compass looks clean upon its surface , it is believed to be in a perfect state , although it may have been stowed away with the card upon the pivot without any protection , thus interfering with the most important of its working parts ; as a consequence , the card , when required for use , will be sluggish upon its pivot , and a false indication of the direction of the vessel 's head is an unavoidable result . 4 . A defective adjustment of the compass is again a vital source of error . This mainly depends , 1 , on the locality in which the vessel is swung , which is too often a dock , where other iron vessels lie in dangerous proximity ; 2 , a want of due precaution on the part of the adjuster , in the place selected for the shore-compass . This is a matter of great importance , far more than is often supposed . As the corrections made on board necessarily depend upon the bearings given from the shore , if these are faulty , the ship 's compass cannot be otherwise than incorrect . The author has more than once seen a shore-compass within a very short distance of an iron shed . The prevailing practice of swinging a ship in the short space of two hours is also very objectionable ; it is utterly impossible to regulate compensating magnets , and to make the requisite observations for the use of soft iron , in so short a time ; it does not allow the vessel to be stayed upon the several points for a sufficient scrutiny of the compasses , sometimes three in number , and the results are too often merely guessed at , and thus all the advantages of that admirable system of adjusting iron vessels ' compasses , introduced by the Astronomer Royal , and which are invaluable to our coasting and short voyage vessels , are , to a great extent , negatived . London is unfortunately very badly provided with the means of adjusting the compasses of iron vessels , and , as their number is so much increasing , this subject is daily becoming more important ; the docks are crowded , and it is by mere chance that in the Victoria Dock , the only available dock at our command , a sufficiently clear space is to be met with . Greenhithe remains as the last resource in this dilemma ; here moorings have been laid down by the City authorities for the use of merchant-vessels , but they are too near the edge of the tide . A very strong down current exists ; the entire space of slack water in the Reach is occupied by two sets of moorings for the use of the Royal Navy , It would be a very great boon if one of these sets of moorings were allowed to be used by the merchant service , when not required for Her Majesty 's Navy . It rarely happens that both sets of moorings are at the same time required for use . As the swinging a ship , moreover , at Greenhithe is entirely dependent upon the tide , it must be commenced with the flood , added to which , the operation is often much impeded by the wind , so that in the winter months , when the days are short , and the seven hours of ebb occur during nearly the whole of daylight , much serious delay is the result ; the author has often occupied three days in adjusting a ship 's compasses . The construction of a dock for this purpose would be very desirable ; the expense may be urged against the proposal ; but surely in London , one of the greatest mercantile cities in Europe , such an undertaking should be regarded as a national matter , and it is believed that shipowners would not object to pay a small rate of charge for the use of such a dock which might render it self-supporting . An opportunity for constructing such a dock may possibly arise in the formation of the new docks at Dagenham , where the expense of an entrance would be saved by simply making a basin from the dock large enough to swing a ship 400 feet in length round a dolphin placed in the centre , and well supplied with mooring-posts for ropes to be made fast to , and a suitable spot for the shore observer--of course removed from all possibility of attraction by iron in the immediate vicinity ; such basin to be kept exclusively for this purpose , and known as " The Ship-swinging , " or " The Compassadjusting " Dock . With the view of deducing a practical result from what has been advanced in the foregoing remarks , the author would most strongly urge the necessity of some offcial inspection of iron vessels with reference to their compass-fittings . A code of rules and instructions might be laid dowi for this purpose ; this would be essential in the cases of new ships ; old ships should be examined at stated times , and certificates of compass adjustment be recognized by the appointed officer solely from those who can furnish evidence of having been properly instructed by competent persons , so that such an important work should not be allowed to be taken up and carried on by any amateur as his fancy may dictate . It may be a question how far a Government inspection would be cordially received by shipowners or public companies ; it might by some be regarded as an undue interference ; the Government also might be indisposed to incur the cost of an extra office , with all its details ; it mright be more properly thought a matter for the consideration of Lloyd 's . It is a question assuredly in which underwriters are largely and personally interested , and they already hold arbitrary powers as concerns the construction of the hull of a ship . The simple question of the compass as a means of safety is comparatively disregarded . The above suggestions are offered with great deference , and the author would rather leave the subject in the hands of those more conversant with legislation than himself ; but he cannot refrain from repeating that the results of his own practical experience ( which has been of no small amount ) convince him that an official supervision1 of the compass-fittings of iron ships has become , from various causes , absolutely requisite .

112586

3701662

On the Tidal Currents on the West Coast of Scotland

42

46

Proceedings of the Royal Society of London

Archibald Smith

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6.0.4

http://dx.doi.org/10.1098/rspl.1866.0016

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112586

10.1098/rspl.1866.0016

http://www.jstor.org/stable/112586

Geography

Meteorology

Geography

III . " On the Tidal Currents on the U W\est Coast of Scotland . " By ARCHIIBALD SMlITI , M.A. , ? F..S . Received March 1 , 1866 . The tidal currents on that part of the west coast of Scotland which is comprised between the Mull of Cantyre and the Island of Mulll r]un in general with great velocity . Their velocity , direction , and the time of their change , or of slack water , are therefore matters of great importance to navigators . On the other hand , the rise and fall of the tide is so small , and the depth of water in the chaninels and the harbours so considerable , that the times of high and low water are of comparatively small importance . While the laws of the currents are thus of more importance than the laws of the rise and fall of the tide , they are also much more simple . The times of high and low water are very different at different parts of the [ Mar. 8 , coast , while the times of slack water are nearly the same throughout the whole region in question . In a great part of this region the current , which sets for six hours in one direction , has no distinct title to be considered . either a flood tide or an ebb tide . The consequence is , that to describe the laws of the currents by reference to the time of high and low water , introduces great and unnecessary complexity . The application to the currents of the method first applied by Admiral Beechey to the tidal stream of the Englisih C(hannel and German Ocean ( Phil. Trans. 1851 , p. 703 ) introduces at once order and simplicity , and makes that intelligible which before was only a confutsed maze . In the following paper an attempt is made , from the materials to be found in the charts of the Admiralty Survey of the west coast of Scotland , now nearly completed , to obtain a first approximation to a tidal chart of the west coast of Scotland . For this purpose I have , with the kind assistance of Commander Evans , F.R.S. , the first Naval Assistant to the iHydrographer of the Navy , deduced from the charts all the information to be there found as to the direction and times of change of the tidal streams , as well as the times of high and low water . The latter are indicated in the usual way by Roman numerals , which , to avoid confusion , are always within the land . The times of change and direction of the currents are described by a particular symbol which I have found convenient for the purpose , and which I will now describe . In the seas which we are considering , the stream at any point generally flows for six hours in one direction and for six hours in the opposite direction . This may be conveniently indicated by the following symbol:which indicates a stream flowing from XII . o'clock to VI . towards the east , and from VI . to XII . towards the west . In this notation , for simplicity , the interval of the tide is considered as 12 hours instead , as it really is , about 1211 2 'm . T bhe hours are expressed in Greenwich mean time . The same symbol is adapted to the case of a stream flowing longer in one direction than in the other . Thus in the Sound of Sanda the stream at full and change may be indicated by V xj indicating that it flows seven hours towards the west and five hours to the east . The velocity of the stream may be expressed by the length of the figure , or sometimes more conveniently by separate lines , the terminations of which are well marked as --- , the length of the lines indicating either the velocity at the middle of the stream , or , if it is found more conveniient , the whole distance which a particle of water moves in one tide . E2 I may observe that an analogous symbol may be used to express the more complicated tides which occur where different streams meet . Thus near the Eddystone the stream may be expressed by a symbol of this kind:4 the bearing and distance of the centre of the diagram from any inumeral indicating the direction and rate of stream at that hour . The time of high and low water in the region which we are considering may be thus described . Near the two extremities , viz. the Giant 's Causeway and the Island of Eysdill , the time of high water at full and change is nearly VI Greenwich time , being very nearly that due to the Great Atlantic tidal wave propagated from S.W. to N.E. , and the same is very nearly the hour of high water on the chain of islands of which Isla , Jura and Scarba are the chief . But along the coast of the mainland of Ireland and Scotland the case is very different . Between these two countries is the great opening into the Liverpool basin , in which it is high water about XI . The change in the time of high water takes place by the following gradations:-At Giant 's Causeway it is high water about VI , , at Ballycastle VII . , Torpoint X. , Mull of Cantyre XI . , Gigha II . , Loch Killispoint IV . , Eysdill and Scarba V , Jura and Islay VI . But while the hour of high water varies , the stream through nearly the whole of the region runs from X. to IV . in one direction and from IV . to X. in the other . Between the Mull of Cantyre and the N.E. coast of Ireland , the X. to IV . stream runs to the north . The most westerly part turns to the west , and runs through the Sound of Rathlin along the north coast of Ireland ; the central part flows to the N.W. past the lihynns of Islay ; the easterly part , which has flowed partly through the Sound of Sanda , turns sharply round the Mull of Cantyre , and flows to the northward , pouring with great velocity through the narrow openings in the chain of islands , viz. , the Sound of Islay between Islay and Jura , the Gulf of Corry Vreckan between Jura and Scarba , the little Corry Vreckan between Scarba and Lunga , the Slate Isles and the Cuan Sound ; of these the little Corry Vreclsan is quite impassable ; and Corry Vreckan and the Cuan Sound are seldom attempted except near slack ' , ater . These channels open into the basin which lies between Jura and Iona-a comparatively tideless sea , owing apparently to the circumstance of the ocean tide from the outside of Isla rising to nearly the same height as that b ' " " " " ' ' " " " '^ " which pours through the openings , so that the tidal stream would be little altered by building a dam from Islay to the Ross of Mull . The question may now be asked , Is the great X. to IV . stream which has just been described a flood or an ebb tide ? So far as regards the Mull of Cantyre , Fairhead , and all that lies to the south or east , it is a true ebb tide . So far as regards Jura , Scarba , and the coast to the north and east , it is a true flood tide ; but as regards a great part of the region in question , it cannot be called either a flood or an ebb tide , and much confusion is occasioned in the Charts by attempting so to distinguish it . At the south end of Gigha in the Admiralty charts an arrow is laid down , indicating that the flood tide runs to the northward ; and a few miles south of this , another arrow is laid down , indicating that the flood tide runs to the southward . From these arrows we might expect to find at this place a meeting of the tide and a sudden change in the direction of the flood stream . But the stream which is indicated by these arrows is nothing more than the great X. to IV . northerly current which we have described . The spot which is treated as a meeting of the tides , is merely that at which it is high water at I. North of this , for more than three hours of the X. to IV . stream , the tide is rising , and it is indicated as a flood tide . South for more than three hours the tide is falling , and it is indicated as an ebb tide . On the south and west coast of Isla the confision is greater . In some of the charts , the incoming stream is marked as the flood , in others , and perhaps with better reason , the outgoing tide . It is in truth neither the one nor the other . The extreme complication which arises from describing the time of change of the stream by reference to the time of high and low water will now appear ; thus we should have to say that in the Sound of Sanda , the ebb stream begins two hours before high water ; at the Mull of Cantyre , one hour before high water ; a little north of this again two hours before high water . At the south of Gigha we might say indifferently , that the flood tide runs to the south and begins three hours before low water , or that it runs to the north and begins three hours after low water ; in the Sounds of Islay and the Gulf of Corry Vreckan that it begins an hour before low water ; and in describing the streams along the north coast of Ireland , we have even greater complication . The direction of the tidal streams on the rest of the west coast of Scotland is easily described . The X. to IV . stream , through the course which I have described , becomes an XI . to V. stream at the outside of Isla , and through the Sound of lona . The stream which sets to the northward up the Sound of Jura fills the Linnhe Loch , and causes high water at the south end of the Sound of Mull at half-past V. , whilst the high water caused by the ocean tide at the north end of the Sound of Mull is an hour later ; the consequence , as may easily be seen , is that nearly the whole flood tide through the Sound of Mull runs to the northward , and the nearly whole ebb tide runs to the southward . The tides round the island of Sky are comparatively simple . The V. to XI . tide from the outside of Mull is gradually retarded to a VI . to XII . stream at the outside of Sky , and then as it rounds the north end of Sky , it is met by the tidal stream which has rounded the north end of the island of Lewis , and bends round into the inner Sound of Skve , where it becomes a VII . to I. tide ; the course of both streams being nearly the same as if there were an embankment from Loch Shell in the island of Lewis to Ru Rea on the coast of Ross-shire . At the same time , another branch of the tide which has rounded the point of Ardnamurchan flows through the Sound of Sky as a XII . to VI . tide , and being an hour earlier than the tide which has rounded the north end of Sky , it pours with great velocity through Kyle Rea , but only to fill Loch Alsh and Loch Duich ; the retardation which it meets with in so doing , making the rise inside of the narrows at Kyle Akin so nearly contemporaneous with the rise outside , that there is little stream through that narrow opening ; the flood stream , as I am informed , sometimes flowing in one direction and sometimes in the other , according to the prevailing winds . There are many more minute details in these streams which have features of great interest . I have not , however , ventured in the present imperfect state of the data which we possess to enter upon these . I ventlre , however , to express a hope that before the survey is completed , the data may be obtained for showing , and that the charts may show the direction and rate of the stream at every place and at any time .

112587

3701662

On a Possible Geological Cause of Changes in the Position of the Axis of the Earth's Crust

46

54

Proceedings of the Royal Society of London

John Evans

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0017

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112587

10.1098/rspl.1866.0017

http://www.jstor.org/stable/112587

Fluid Dynamics

Geography

Fluid Dynamics

" On a possible Geological Cause of Changes in the Position of the Axis of the Earth 's Crust . ' By JO . HN EVANS , F.R.S. Sec. G.S. Received February 28 , 1866 . At a time when the causes which have led to climatal changes in various parts of the globe are the subject of so much discussion , but little apology is needed for calling the attention of this Society to what possibly may have been one of these causes , though it has apparently hitherto escaped observation . That great changes of climate have taken place , at all events in the northern hemisphere of the globe , is one of the best established facts of geology , and that corresponding changes have not been noticed to the same extent in the southern hemisphere may possibly be considered as due , rather to a more limited amnount of geological observation , than to an absence of the phenomena indicative of ' suchi alterations in climatal conditions having occurred . [ Mar. 15 , The evidence of the extreme refrigeration of this portion of the earth at the Glacial Period is constantly receiving fresh corroboration , and various theories have been proposed which account for this accession of cold in a more or less satisfactory mannaer . Variations in the distribution of land and water , changes in the direction of the Gulf-stream , the greater or less eccentricity of the earth 's orbit , the passage of the Solar System through a cold region in space , fluctuations in the amiount of heat radiated by the sun , alternations of heat and cold in the northern and southern hemispheres , as consequent upon the precession of the equinoxes , and even changes in the position of the centre of gravity of the earth and consequent displacements of the polar axis , have all been adduced as causes calculated to produce the effects observed ; and the reasoning founded on each of these data is no doubt familiar to all . The possibility of any material change in the axis of rotation of the earth has been so distinctly denied by Laplaceand all succeeding astronomers , that any theory involving such a change , however tempting as affording a solution of certain difficulties , has been rejected by nearly all geologists as untenable . Sir I-enry Jamest , however , writing to the 'Athenaeum ' newspaper in 1860 , stated that he had long since arrived at the conclusion that there was no possible explanation of some of the geological phenomena testifying to the climate at certain spots having greatly varied at different periods , without the supposition of constant changes in the position of the axis of the earth 's rotation . I-e then , assuming as an admitted fact that the earth is at present a fluid mass with a hardened crust , showed that slaty cleavage , dislocations , and undullations in the various strata are results which might be expected from the crust of the earth having to assume a new external form , if caused to revolve on a new axis , and advanced the theory that the elevation of mountain-chains of larger extent than at present known produced these changes in the position of the poles . The subject was discussed in further letters from Sir Henry James , the Astronomer Royal , Professors Beete Jukes and I-ennessy , and others , but throughout the discussion the principal question at issue seems to have been whether any elevation of a mountain-mass could sensibly affect the position of the axis of rotation of the globe as a whole , and the general verdict was in the negative . At an earlier period ( 1818 ) the late Sir John Lubbock , in a short but conclusive paper in the 'Quarterly Journal of the Geological Society ' : pointed out what would have been the effect had the axis of rotation of the earth not originally corresponded with the axis of figure , and also mentioned some considerations which appear to have been absent from Laplace 's calculations . * Mec . C61 . , vol. v. p. 14 . t A.thenauinm , Aug. 25 , 1860 , &c. + Vol. v. p. 5 . in the Sir John Lubbock , however , in common with other astronomers , appears to have regarded the earth as consisting of a solid nucleus with a body of water distributed over a portion of its surface ; and there can be but little doubt that , on this assumption of the solidity of the earth , the usually received doctrines as to the general persistenceof the direction of the poles are almost unassailable . Directly , however , that we argue from the contrary assumption that the solid portion of the globe consists of a comparatively thin , but to some extent rigid crust with a fluid nucleus of incandescent mineral matter within , and that this crust , from various causes , is liable to changes disturbing its equilibrium , it becomes apparent that such disturbances may lead , if not to a change in the position of the general axis of the globe , yet at all events to a change in the relative positions of the solid crust and the fluid nucleus , and in consequence to a change in the axis of rotation , so far as the former is concerned . The existence in the centre of the globe of a mass of matter fluid by heat , though accepted as a fact by many , if not most geologists , has no doubt been called in question by some , and among them a few of great eminence . The gradual increase of temperature , however , which is found to take place as we descend beneath the surface of the earth , and which has been observed in mines and deep borings all over the world , the existence of hot springs , some of the temperature of boiling water , and the traces of volcanic action , either extinct or still in operation , which occur in all parts of the globe , afford strong arguments in favour of the hypothesis of central heat . And though we are at present unacquainted with the exact law of the increment of heat at different depths , and though , no doubt , under enormous pressure the temperature of the fusing-point of all substances may be considerably raised , yet the fact of the heat increasing with the depth from the surface seems so well established that it is highly probable that at a certain depth such a degree of heat must be attained as would reduce all mineral matter with which we are acquainted into a state of fusion . When once this point was attained , it seems probable that there would be no very great variation in the temperature of the internal mass ; but whether the whole is in one uniform state of fluidity , or whether there is a mass of solid matter in the centre of the fluid nucleus , are questions which do not affect the hypothesis about to be considered . Those who are inclined to regard the earth as a solid or nearly solid mass throughout , consider that many volcanic phenomena may be accounted for on the chemical theory , which has received the support , among others , of Sir Charles Lyell. . But apart from the consideration that such chemical action must of necessity be limited in its duration , the existence of local seas of fluid matter , resulting from the heat generated by intense chemical action , would hardly account for the increase of heat at great depths in places remote from volcanic centres ; and the rapid transmission of shocks of earthquakes and the enormous amount of upheaval and subsidence as evidenced by the thickness of the sedimentary strata , seem inconsistent either with the general solidity of the globe or any very great thickness of its crust . The supposition that the gradual oscillations of the surface of the earth , of which we have evidence all over the world as having taken place ever since the formation of the earliest known strata up to the present time , are due to the alternate inflation by gas and the subsequent depletion of certain vast bladdery cavities in the crust of the earth , can hardly be generally accepted . Those who wish to see the arguments for and against the theory of there being a fluid nucleus within the earth 's crust , will find them well and fairly stated in Naumann 's 'Lehrbuch der Geognosie'* . AMy object is , not to discuss that question , but to point out what , assuming the theory to be true , would be some of the effects resulting from such a condition of things , more especially as affecting climatal changes . The agreement or disagreement between these hypothetical results and observed facts may ultimately assist in testing the truth of the assumption . The simplest form in which we can conceive of the relations to each other of a solid crust and a fluid nucleus in rotation together is that of a sphere . Let ACBD be a hollow sphere composed of solid materials and of perfectly uniform thickness and density , and let it be filled with the fluid matter E , over which the solid shell can freely move , and let the whole be in uniform rotation about an axis F G , the line CD representing the equator . A - ? cc It is evident that in such a case , the hollow sphere being in perfect equilibrium , its axis and that of its fluid contents would perpetually coincide . 1866 . ] 49 -*2nd edit ; . , 1.858 , vol. i. p. 36 , in the If , however , the equilibrium of the shell or crust be destroyed , as , for instance , by the addition of a mass of extraneous matter at H , midway between the pole and the equator , not only would the position of the axis of rotation be slightly affected by the alteration in the position of the centre of gravity of the now irregular sphere , but the centrifugal force of the excess of matter at 11 would gradually draw over the shell towards D until , by sliding over the nucleus , it attained its greatest possible distance from the centre of revolution by arriving at the equator . The resultant effect would be that though the whole sphere continued to revolve around an axis as nearly as possible in the line F G , yet the position of the pole of the hollow shell would have been changed by 45 ? , as by the passage of II to the equator the points I and K would have been brought to the poles by spirals constantly decreasing in diameter , while A and B , by spirals constantly increasing , would have at last come to describe circles midway between the poles and the equator . The axis of rotation of the hollow sphere and that of its fluid contents would now again coincide , and would continue to do so perpetually unless some fresh disturbance in the equilibrium of the shell took place . If instead of the addition of fresh matter at H1 we had supposed an excavation or removal of some portion of the shell , a movement in the axis of rotation of the shell would also have ensued , since from the diminished centrifugal force of that portion of the hollow sphere where the excavation had taken place , it would no longer equipoise the corresponding portion on the opposite side at I , and the excavated spot would eventually find its way to the pole . In order more clearly to exhibit these effects , I hyave prepared a model in accordance with a suggestion of Mr. Francis Galton , F.R.S. , in which a wheel representing a section of a hollow sphere has its axis , upon which it can freely turn , fixed in a frame , which is itself made to revolve in such a manner that the axis of its rotation passes through one of the diameters of the wheel , and coincides with what would be the axis of the sphere of which the wheel is a section . In the periphery of the wheel are a number of adjustable screws with heavy heads , so that , by screwing any of them in or out , the addition of matter or its abstraction at any part of the sphere may be represented . If by adjusting these screws the wheel could be brought into perfect equilibrium , its position upon its own axis would remain unchanged in whatever position it was originally placed , notwithstanding any amount of rotation being given to the frame in which it is hung ; but practically it is found that with a certain given position of the screws a certain part of the wheel coincides with the axis of the frame , or becomes the pole around which the sphere revolves . The rim of the wheel is graduated so as to show the position of the poles in all cases , and generally speaking the wheel always settles down after rotation with the pole within three or four degrees of the same spot , if no alteration has been made in the adjustment of the screws , though of course what was the uppermost pole may become the lower one ; and in some cases the wheel may be in equilibrio with a projecting screw either above or below the equator , in which case there may be four readings on the circle at the index-point , according as the one pole or the other is uppermost , and the projecting screw is above or below the equator . With the screws on the wheel evenly balanced , a slight alteration in the adjustment of any of them immediately tells upon the position of what , for convenience sake , may be called the poles , except , indeed , in such cases as screwing outwards those already at the equator , or making similar alterations in the adjustment of two screws at equal distances on either side of one of the poles . If a screw be turned outwards so as notably to project at any spot , no matter how near to the pole , it will be found , after the machine has been a short time in revolution , in the region of the equator . Or again , if one or , better still , two opposite screws at the equator be turned inwards , they will be found after a short period of revolution at the poles . Now let us assume for a moment that , though the crust was partially covered by water , the earth , instead of being a spheroid , was a perfect sphere , consisting of a hardened qrust of moderate thickness supported on a fluid nucleus over which the crust could travel freely in any direction , but both impressed with the same original rotatory motion , so that without some disturbing cause they would continue to revolve for ever upon the same axis , and as if they were one homogeneous body . Let us assume , moreover , that this crust , though in perfect equilibrium on its centre of rotation , was not evenly spherical externally , but had certain projecting portions , such as would be represented in Nature by continents and islands rising above the level of the sea . It is evident that so long as those continents and islands remained unaltered in their condition and extent , the relative position of the crust to the enclosed fluid nucleus would remain unaltered also . But supposing those projecting masses were either further upheaved from some internal cause , or worn down and ground away by the sea or by subaerial agency and deposited elsewhere , it seems impossible but that the same effects must ensue as we see resulting upon the model from the elevation and depression of certain screws , and that the axis of rotation of the crust of the sphere would be changed in consequence of its having assumed a fresh position upon its fluid nucleus , though the axis of the whole sphere might have retained its original direction , or have altered from it only in the slightest degree . An irregular accumulation of ice at one or both of the poles , such as supposed by M. Adhdeftar , would act in the same manner as an elevation of the land ; and even assuming that the whole land had disappeared from above the surface of the sea , yet if by marine currents the shallower parts of the universal ocean were deepened and the deeper parts filled up , in the there would , owing to the different specific gravity of the transported soil and the displaced water , be a disturbance in the equilibrium of the crust , and a consequent change in the position of its axis of rotation . Now if all this be true of a sphere , it will also , subject to certain modifications , be true of a spheroid so slightly oblate as our globe . The main difference in the two cases is , that in a sphere the crust may assume any position upon the nucleus without any alteration in its structure , while in the case of the movement of a spheroidal crust over a similar spheroidal nucleus , every portion of its internal structure must be more or less disturbed as the curvature at each point will be slightly altered . The extent of the resistance to an alteration of position arising from this cause will depend upon the oblateness of the spheroid and the thickness and rigidity of the crust ; while the thicker the latter is , the less also will be the proportionate effect of such elevations , subsidences , and denudations as those with which we are acquainted . The question of friction upon the nucleus is also one that would have to be considered , as the internal matter though fluid might be viscous . It will of course be borne in mind that the elevations and depressions of the surface of the globe are not , on the theory now under consideration , regarded according to the proportion they bear to the earth 's radius , but according to their relation to the thickness of the earth 's crust ; and that , even assuming Mr. Hopkins 's extreme estimate to be true , yet elevations or depressions , such as we know to have taken place , of 8000 or 10,000 feet , bear an appreciable ratio to the 800 or 1000 miles which he assigns as the thickness of the earth 's crust . It is , however , to be remarked that the extremely ingenious speculations of Mr. Hopkins are based on the phenomena of precession and nutation , and that if once the possibility of a change in the position of the axis of rotation of the earth 's crust be admitted , it is not improbable that the value of some of the data upon which the calculations of these movements are founded may be affected . The supposition of the thickness of the crust being so great seems also not only entirely at variance with observed facts as to the increase of heat on descending beneath the surface of the earth , but to have been felt by Mr. Hopkins himself to offer such obstacles to any communication between the surface of the globe and its interior , that he has had recourse to an hypothesis of large spaces in the crust at no great depth from the surface , and filled with easily-fusible materials , in order to account for volcanic and other phenomena . But though it may be possible to account for volcanoes upon such an assumption , yet , as already observed , the phenomena of elevation and depression , such as we find to have taken place , and more especially the existence of vast geological faults , cannot without enormous difficulty be reconciled with such a theory . Taking the increment of heat as 1 ? Fahrenheit for every 55 or 60 feet* in descent , a temperature of 24000 Fahr. would be reached at about 25 miles , sufficient to keep in fusion such rocks as basalt , greenstone , and porphyry ; and such a thickness appears much more consistent with the fluctuations in level , and the internal contortions and fractures of the crust which are everywhere to be observed . Sir William Armstrong , on the assumption of the temperature of subterranean fusion being 3000 ? Fahr. , considers that the thickness of the film which separates us from the fiery ocean beneath would be about 34 miles . Even assuming a thickness of 50 miles , so as to make still greater allowance for the increased difficulty of fusion under heavy pressure , the thickness of the crust would only form one-eightieth part of the radius of the earth ; or if we represent the earth by a globe 13 feet in diameter , the crust would be one inch in thickness , while the difference between the polar and equatorial diameters would be half an inch . In such a case , the elevation or wearing away of continents such as are at present in existence , rising , as some of them do , nearly a quarter of a mile on an average above the mean sea-level , would cause a great disturbance in the equilibrium of the crust , sufficient to overcome considerable resistance in its attempts to regain a state of equilibrium by a movement over its fluid nucleus . Whether the thickness of the earth 's crust was not in early geological times less than at present , so as to render it more susceptible of alterations in position-whether the spheroid of the fluid mineral nucleus corresponds in form with the spheroid of water which gives the general contour of the globe-whether or no there are elevations and depressions upon the nucleus corresponding to some extent with the configuration of the outer crust , and whether the motion of the crust upon it , besides effecting climatal changes , might not also lead to some elevations and depressions of the land , and produce some of the other phenomena mentioned by Sir Henry James , are questions which I will leave for others to discuss . My object is simply to call attention to what appears to me the fact , that if , as there seems reason to suppose , our globe consists of a solid crust of no great thickness resting on a fluid nucleus , either with or without a solid central core , and if this crust , as there is abundant evidence to prove , is liable to great disturbances in its equilibrium , then it of necessity follows that changes take place in the position of the crust with regard to the nucleus , and an alteration in the position of the axis of rotation , so far as the surface of the earth is concerned , ensues . Without in the slightest degree undervaluing other causes which may lead to climatal changes , I think that possibly we may have here a vera causa such as would account for extreme variations from a Tropical to an Arctic temperature at the same spot , in a simpler and more satisfactory manner than any other hypothesis . The former existence of cold in what are now warm latitudes might , and probably did in part , arise from other causes than a change in the axis of rotation , but no other hypothesis can well account for the existence of traces of an almost tropical vegetation within the Arctic circle . Of the former existence of such a vegetation , the evidence , though strong , is not conclusive . But if the fossil plants of Melville Island , in lat. 7.5 ? N.@ , which appear to agree generically with those from the English coal-meastires , really grew upon the spot where they were now discovered , they seem to afford conclusive evidence of a change in the position of the pole since the period at which they grew , as such vegetation must be considered impossible in so high a latitude . The corals and Orthoceratites from Griffiths Island and Cornwallis Island , and the liassic Ammonites from Point Wilkie , Prince Patrick 's Island , tell the same story of the former existence of something like a subtropical climate at places at present well within the Arctic circle . To use the words of the Rev. Samuel I aughton:t , in describing the fossils collected by Sir F. L. MeClintock , " The discovery of such fossils in situ , in 76 ? N. latitude , is calculated to throw considerable doubt upon the theories of climate , which would account for all past changes of temperature by changes in the relative position of land and xvater on the earth 's surface ; " and I think that all geologists will agree with this remark , and feel that if the possibility of a change in the position of the axis of rotation of the crust of the earth were once admitted , it would smooth over many ? difficulties they now encounter . That some such change is indeed taking place at the present moment may not unreasonably be inferred from the observations of the Astronomer Royal , who , in his Report to the Board of Visitors for 186 l , makes use of the following language , though " only for the sake of embodying his description of the observed facts , ' as he refers the discrepancies noticed to " some peculiarity of the instrument ... . . The Transit Circle and Collimators still present those appearances of agreement between themselves and of change with respect to the stars which seem explicable only on one of two suppositions-that the ground itself shifts with respect to the general Earth , or that the Axis of Rotation changes its position . " .

112588

3701662

On the Action of Trichloride of Phosphorus on the Salts of the Aromatic Monamines

54

62

Proceedings of the Royal Society of London

A. W. Hofmann

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0018

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112588

10.1098/rspl.1866.0018

http://www.jstor.org/stable/112588

Chemistry 2

Fluid Dynamics

Chemistry

I. " On the Action of Trichloride of Phosphorus on the Salts of the Aromatic Monamines . " By A. W. IIOFMANN , LL. D. , F.1.S . , &c. Received March 3 , 1866 . The starting-point of the following experiments was an accidental observation . Whilst investigating the chlorine- , bromine- , and nitro-derivatives of aniline , I had prepared a large quantity of phenylacetamide by the action of chloride of acetyl on aniline . From the hydrochlorate of aniline , abundantly produced as a by-product in this reaction , the aniline was recovered by treating the mother-liquors with hydrate of sodium . During the distillation , after the greater part of the aniline had passed over and collected in the receiver , a tenacious oily fluid began to come over , adhering to the tube of the condenser and gradually becoming a crystalline mass . It was easily purified by washing with cold , and crystallization from hot alcohol . Beautiful white leafy crystals were thus obtained , fusible at 137 ? , and volatile without decomposition at a temperature beyond the range of the mercury-thermometer . These crystals are almost insoluble in water , difficultly soluble in cold , but soluble in hot alcohol , and also soluble in ether . The solutions are neutral . In acids the crystals are also easily soluble ; an alkali precipitates the original substance unaltered frora the solutions . The hydrochloric-acid solution yields , with tetrachloride of platinum , a difficultly soluble crystalline precipitate . The new substance thus exhibits the deportment of a well-characterized base . Its composition was readily determined by combustion with oxide of copper , the analytical results pointing unequivocally to the formula C7 71 N as the simplest atomic expression for the new body . But the whole behaviour of the substance , and more especially its transformation , by means of concentrated sulphuric acid , into aniline and acetic acid , leave no doubt that the above expression must be doubled , and that the new base is repre , sented by the formula Cl I-1 N2 . This formula was confirmed by the analysis of the platinum-salt already mentioned , and that of the nitrate which separates from the solution as an oily fluid , gradually changing to a beautiful crystalline compound ; the former contains 2(C1 11 N , IIC1 ) , Pt *C1 , the latter C , l Hi1 N , , HN03 . Whence is this body derived ? and how is its formula to be interpreted ? An answer to these questions was furnished by examining the chloride of acetyl employed in preparing the phenylacetamide . When on distilling the chloride the principal product had passed over , the thermometer gra* Pt=198 . dually rose from 55 ? to 78 ? . The last portion which came over was pure trichloride of phosphorus . It was obvious that this substance must have played a part in the formation of the new compound . I therefore submitted phenylacetamide to the action of trichloride of phosphorus . The new body was formed , but in very unsatisfactory quantity . The result of the experiment was essentially different when phenylacetamide and aniline in varying proportions were jointly submitted to the action of trichloride of phosphorus . The amount of substance obtained varied with the composition of the mixture , and appeared greatest when the mixture was made in the proportion of one part of trichlloride of phosphorus , two parts of aniline , and three parts of phenylacetamide . Hence the reaction had taken place according to the following equation : 3 C6 7N+3 C,8 H NO + PC3 =3 C14 H14 N2 + 113 PO3 +3 HC1 . Perfectly similar results were obtained when a proportionate quantity of hydrochlorate of aniline was employed instead of aniline in this experiment . The idea naturally presented itself to produce the same result without taking the trouble of preparing and purifying the phenylacetamide by including its preparation in the very process of forming the new compound . For this purpose 6 molecules of aniline were added to 3 molecules of chloride of acetyl , and the dense liquid thus 'obtained mixed with 1 molecule of trichloride of phosphorus . The result could not have been better : 6C , , N +3C13 OCIl+PCI3=3 C3 , HI N , + H3 P 3+ 6 HC1 . A simple additional step and the true mode of preparing the substance , and with it the general method for the production of an endless variety of analogous bodies , was found . Evidently it was not even necessary to prepare the chloride of acetyl separately . The new body must be as easily obtained by the direct action of trichloride of phosphorus on aniline and acetic acid . The mixture had only to be made in such a manner that , after transforming the acetic acid into chloride of acetyl , there was a sufficient amount of trichloride of phosphorus left to perform the rest of the work . In this case , therefore , 6 molecules of aniline and 3 molecules of acetic acid had to be added to 2 inolecules of trichloride of phosphorus , 6C , H , N +3 CH2 0 , +2PC13 -3C 11 , N + , 2 13 P03 6HC1 . The reaction is violent , and the operation must be performed with care . The substances are mixed according to the above equation . For this purpose three parts by weight of aniline are added to one part of acetic acid and into the mixture surrounded by cold water two parts of trichioride of phosphorus are slowly poured ; in which proportion the latter compound is in slight excess . The tenacious fluid thus obtained is then heated for a couple of hours to 160 ? . On cooling , it solidifies to a hard , friable , translucent , resinous mass of a light-brown colour , which dissolves in boiling water almost without residue , leaving only traces of an amorphous yellow substance containing phosphorus behind . The clear filtered solution , after cooling , yields , on the addition of soda , a white crystalline precipitate , which requires only to be washed and recrystallized from alcohol . The foregoing equations give a pretty clear idea of the qualitative and quantitative nature of the experiment , but they do not afford us an insight into the true mechanism of the reaction . This , nevertheless , is a very simple one . Trichloride of phosphorus acts water-generating and waterwithdrawing . The oxygen required for this purpose is supplied by the pheliylacetamide ; as , however , the molecule of this compound contains but one atom of hydrogen belonging to the original ammonia skeleton , a molecule of aniline is required in addition to supply the second atom of hydrogen . In this manner a diamine is formed , in which two atoms of the hydrogen of the double ammonia type are replaced by two univalent phenyl-residues , and three of the remaining hydrogen atoms by the trivalent group C2 H1 , to which the term ethenyl * may for the present be applied . The new body would thus become ethenyldiphenyldiamine , the formation of which in the most simple form would depend upon the removal of 1 mol . of water from 1 mol . of phenylacetamide and 1 mol . of aniline . C , , j > N -N N==1 + ( C6 HA )2 N , . Hi 3H1 I-I H3 I was anxious to test this assumption by experiment . At 100 ? iodide of ethyl has no action on ethenyldiphenyldiamine , but at about 150 ? the two bodies react on one another . The mixture , after being heated for five or six hours , yielded , upon cooling , beautiful crystals of an iodide . By treatment with chloride of silver this iodide was converted into the corresponding chloride , and then into the platinum-salt . Analysis of this salt showed that the ethyl group had been once taken up . On the addition of caustic soda the corresponding base was separated . It is a thick oily fluid , which , when shaken with water , does not impart to it the slightest alkaline reaction . By renewed treatment with iodide of ethyl an iodide , it is true , was separated , but it was proved on examination that the ethyl group had not been assimilated a second time . In the sense of the above assumption , this nevertheless ought to have taken place . The experiment was therefore repeated with iodide of methyl which is well known to act much more powerfully than the ethyl-compound . This body attacks the ethylated base even at 100 ? . The iodide thus obtained , when decomposed by oxide of silver , yielded a strongly lalkaline liquid , whence quantivalence of the residuary group again increases , the groups becoming quadri . valent and quintivalent , and acquiring the terminations in and inyl , &c. According to this principle the following names are formed : Methane , ( C H4 )o Sextane , ( C6 H14 ) ? Ethane , ( C2 He )o Septane , ( C , H116 ) Propane , ( C3 H8 )o Octane , ( C8 HI18 ) Quartane , ( C4 Hio)0 Nonane , ( C9 IH20 ) Quintane , ( C5 H112 ) Decane , ( CIo H22 ) ? And further : Methane , ( C H1)J 'Ethane , ( C20 1)0 Propane , ( Ca H8 ) ? Quartane , ( I H10 ) ? Methyl , ( C H13 ) Ethyl . ( C2 H5 ) ' Propyl , ( C H ) ' Quartyl , ( C4 1 , ) ' Methene , ( C 12 ) " Ethene , ( C21 ) " Propene , ( C311H ) " Quartene , ( C4s ) " Methenyl , ( C H ) " ' Ethenyl , ( C2 ) " ' Propenyl , ( Ca { O ) " ' Quartenyl , ( C4H ) " ' Ethine , ( C2 H2)iV Propine , ( C3 H)iv Quartine , ( C 116)iV Ethinyl , ( C0 I7 Propinyl , ( C 1H3 ) V Quartinyl , ( 04 H)V Propone , ( C3 H2 ) , i Quartone , ( 04 4)vi Proponyl , ( Ca I{)vii Quartonyl , ( C4 113)ii Quartune , ( O4 I2)viii Quartunyl , ( C4 H )i This is not the place to develope this subject further . The short notice I have given must suffice . A superficial examination of the system shows , however , how large a number of groups of atoms may be clearly and succinctly expressed in it . It appeared convenient to submit the plan to a provisional test by framing some of the names required for the substances which were furnished by the above experiments . Bodies containing oxygen may be as simply nominated according to this plan . The acid derived from ethylic alcohol is ethoxylic acid ( acetic acid ) , the first acid corresponding to ethenic alcohol would be etho.xenic acid ( glycolic acid ) , the second being ethdioxenic acid ( oxalic acid ) . We speak of the oxylic , oxenic , and dioxenic acids of a series , of the quartane series , for inlstance , and any one would understand that by these expressions are meant butyric , butylactic , and succinic acids . it was at once inferred that the methyl group had been added to the ethyl group already present in the substance . This conclusion was amply corroborated by the analysis of the platinum-salt precipitated from the liquid . By this experiment the nature of ethenyldiphenyldiamine is most satistorily elucidated . The action of iodide of ethyl had converted this base into the tertiary diamine ethenylethyldiphenyldiamine , ( C2 H3 ) ; ( C2115 ) N2 ; ( C6 11)2 J the latter , under the influence of iodide of methyl , yielding the compound [ ( C2 113 ) " ' ( C2 11 ) ( C6 Ha ) > N2 ] ( C H3 ) } , which is soluble in water with a strongly-marked alkaline reaction . The stability of ethenyldiphenyldiamine is remarkable . As I have already mentioned , this base distils at a very high temperature without decomposition . It is moreover scarcely attacked by fision with hydrate of potassium . Concentrated sulphuric acid , on the other hand , decomposes it easily . When gently heated , the solution of ethenyldiphenyldiamine in sulphuric acid evolves acetic acid , and , on addition of water , the slightly-coloured liquid solidifies to a white crystalline mass of sulphanilic acid , ( 0 211)2 }H 11C2 r0C io5 ( C s)2 N 2+2H SO= 3 o+2 HN 83 RH H It need scarcely be mentioned that , by reactions similar to that of trichloride of phosphorus on acetate of aniline , an almost endless variety of new compounds may be obtained . By changing the acid , or base , or both , a series of substances is formed , the composition of which in each case is fixed in advance by theory . I have worked only very little in this direction . Toluidine acts in a manner precisely similar to that of aniline . The base formed can scarcely be distinguished from the phenyl base . Analysis of the platinum-salt has led to the formula ( C2 ) " ' ) 16 I,18 N2= ( C , H7)2 N2 . With naphthylamine the reaction is less smooth . The product obtained by acting with 1 molecule of trichloride of phosphorus on 3 molecules of chloride of acetyl and 6 molecules of naphthylamine , was an unenjoyably viscous scarcely crystalline mass which retained , after repeated solution and precipitation , its amorphous character . An analysis of the platinumsalt led , however , to the formula ( C2 1H3 ) " C22 1 N2= ( CO 117)2 N2 . toluidine , and naphthylamine being primary monamines , it seemed of interest also to extend the examination to a secondary one . For this purpose I selected diphenylamine . When a mixture of diphenylamine and phenylacetamide , in the proportion of their molecular weights , was submitted to the action of trichloride of phosphorus , the reaction took place in the ordinary way , but the mass precipitated from the solution of the chloride by ammonia could not be crystallized . It had therefore to be analyzed as platinum-salt . Determination of the platinum as well as combustion showed , however , that the expected ethenyltriphenyldiacmine had been formed , C2 1130 C6 1-5 N ( C2 13 ) " C , H1 N+C , H+ N= 0+ ( ( , . ) , 2 N.2 , II~J ( C( J-J- ) J An entirely unexpected result , on the other hand , was obtained by the action of triclloride of phosphorus on a mixture of acetic acid and methylaniline . Working , as I did , exclusively with a secondary monamine , I had expected to see the reaction take place according to the following equation:rCi3 Oc io-1 ( C2 113 ) " 3 C6JI , N+2 }0=2 1O +(C H3)3 N3 . L IH ( C 115 J_3 But this was not the case ; the action was found to have been very irregular ; and amongst the products a chloride was observed , the base of which , when liberated by oxide of silver , dissolved in water with an alkaline reaction . When analyzed in the form of a platinum salt , this body proved to be ethenyldiphenyldiamlinie , which had twice appropriated the methyl-group , having the composition [ ( C2 H , ) " ( C , Hii , ) ( C H3 ) N , ] C HI , In this case evidently chloride of methyl had been eliminated from one of the molecules of mietliylaniline , which , acting on the ethenyldiphenylmethyldiatnine , had given rise to the formation of the chloride corresponding to the above-mentioned oxide , 2[(C , H1 ) ( C H13 ) HN ] + C2 I3 0 C1= -110 + [ ( C , I- , ) ' " ( C , II ) , ( C HI ) N , ] ( C 11 ) Cl. A few experiments made with the derivatives of valeric and benzoic acids are still to be mentioned . Quintenyldiphenyldiamine.-For the preparation of this substance , 3 molecules of valeric acid were miixed with 6 molecules of aniline , and to the liquid , after cooling , 2 molecules of trichloride of phosphorus were added . This mixture , on being submitted for a couple of hours to a temperature of 150 ? , yielded a viscous mass soluble in water . Fromn the solution hydrate of sodium precipitated a crystalline base almost insoluble in water , which was recrystallized from alcohol . This substance fused at 1 11 ? . The com bustion of the body and the analysis of its platinum-salt , which crystallized in rhombic plates difficultly soluble in water and almost insoluble in alcohol , led to the formula ( C , H1 ) " ' CG7 -20 N2 =(C6 HJ ) N2 . H Benzyldiphenyldiamine.-By substituting benzoic acid for valeric acid in the reaction just described , the corresponding benzyl-compound is obtained . I have prepared this substance by the action of 1 molecule of trichloride of phosphorus on a mixture of 3 molecules of phenylbenzamide and 3 molecules of hydrochlorate of aniline . The reaction takes place in the ordinary way . The product is a very weak base crystallizing in fine silky needles . The hydrochlorate forms thin brilliant plates difficultly soluble in water , which upon re-crystallization lose their acid . The analysis led to the formula ( C7 )'1 C19 Uo16 N2=(C6 HUE , )2 > N2 . HJ This compound has been already observed by Gerhardt . He obtained it whilst examining the action of pentachloride of phosphorus on the amides , the last experiments which he performed before his death . A short notice of this investigation , found after his death , has been published by M. Cahours * . The phenyl-compounds of the acetic and valeric groups above described are naturally linked with a compound which several years ago I procured by an essentially different reaction . This substance , which at the time I described under the name of formyldiphenyldiaminet , but to which , in accordance with my present ideas on nomenclature , I would give the name methenyldiphenyldiamine , is obtained by the action of chloroform on aniline ; its relation to the compounds before mentioned is seen by a glance at the following formule:(C T1 ) ' " Methenyldiphenyldiamine , C13 H1 N2= ( C6 T1s ) N2 . ( C , H1 Ethenyldiphenyldiamine , C , , IH , N= ( C , HI)2 N , . HJ ( C5 J1 ) " ) Quintenyldiphenyldiamine , C7 HI0 N2 =(C6 II)2 N , . It seemed worth while to establish by a special experiment the analogy of methenyldiphenyldiamine , obtained in so different a reaction , with the substances just described . For this purpose I submitted phenylform* Ann. Ch. Phys. [ 3 ] , vol. liii . p. 302 . t Proceedings of the Royal Society , vol. ix . p. 229 . 61 amide* to the action of a mixture of aniline and trichloride of phosphorus . The result proved that the methenyl-compound can be thus prepared even more easily than by means of chloroform . In conclusion , the relation must be mentioned which the compounds just described hear to the base obtained by Professor Strecker t , when acting with gaseous hydrochloric acid on acetamide , The body thus formed is C2 H , N2 ( C2 3)i } N2 , H3 ~ , and has been called acediamine , for which name , in accordance with the proposed nomenclature , I would now substitute the term ethenyldiamine . When compared with the analogous aniline-compound , the very slight stability of acediamine , which splits up with the greatest facility into acetic acid and ammonia , deserves to be noticed . A quintenyldiamine , corresponding to the quintenyldiphenyldiamine , has not as yet been prepared . Methenyldiamine , on the other hand , is known , although the compound which I have in view has scarcely been looked upon as such . The body in question is no other than cyanide of ammonium . ( C I[ ) " ' t ) Methenyl(C I)m } Methenyldiamine ( C H it Methenyl(C H)'N ( Cyanide of ammonium ) dieny ( Ce 5)2 HJ diamine H The facility with which this substance decomposes is well known ; amongst the productsformic acid and ammonia are invariably found . It is further known that by heating ammonia with chloroform ( trichloride of methenyl ) , cyanide of ammonium is formed , a reaction which is perfectly similar to that by which the analogous phenyl-base was originally obtained in the corresponding experiment with aniline . In conclusion , I beg to thank Messrs. Tingle and Fischer for their valuable assistance during the performance of the experiments described .

112589

3701662

Notice of a Zone of Spots on the Sun

63

70

Proceedings of the Royal Society of London

John Phillips

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0019

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112589

10.1098/rspl.1866.0019

http://www.jstor.org/stable/112589

Astronomy

Optics

Astronomy

II . " Notice of a Zone of Spots on the Sun . " By JOHN PHILLIPS , M.A. , LL. D. , F.R.S. , Professor of Geology in the University of Oxford . Received March 22 , 1866 . During the latter half of February and the first half of March , spots of extremely varied character have appeared on the sun , and have been seen with great distinctness , in good observing weather , through the whole or parts of two semi-rotations . On the 13th of February , at 10h 25 ' , four spots were visible on the disk , in the situations marked Z , A , B , C in the diagram No. 1 . In that diagram the apparent course of the sun 's equator is Diagram No. 1.\3 marked by the curved line e , and the pole of rotation at P. Thus the four spots indicated for observation being all on the same side of the sun 's equator , and all within the latitude of 10 ? , constitute a zone of spots . Since that date a fifth spot , D , still in the same zone , has appeared , following C. Of these Z was about to disappear ; its reappearance was noted , and several remarkable changes in form were observed while it traversed half the disk , till its contraction to a black speck 1000 miles in diameter , after which it was obliterated . The spot B had advanced some distance on the disk , and was followed till the 2i st of February , when it approached the edge , with indications of being a shallow concavity . It was not observed to reappear . The spots A and C require longer notice , both on account of their persistence through more than a rotation-period , and because of the remarkable changes which they have undergone . The spot D is now under observation . The spot A , visible from the 4th to the 16th of February , and again reappearing early in March , was solitary , and approximately round , measuring , on February 10 , about 23,000 miles across the penumbra , and about 8000 across the umbra . It had a clear brown tint over the whole penumbra , the body of the sun appearing fairly white , and a deeper brown tint over part of the umbra , the remaining and larger space of the umbra being black . The penumbral space was marked with the broken structure represented in a former communication* . The edges of the umbra and penumbra were much broken , the former running out into a sharp point on the apparent left , and including a lighter brown space . Except in this part , the dark umbra was uniformly and equally distant from the penumbral border , so that it offered an excellent object , large enough and distinct enough to be employed with confidence as a test of the depth of the umbra beneatli the luminous photosphere . In a former communication I assigned to an umbra of good figure , carefully observed , a depth of only 300 milest . Since then M. Chacornac+ has given the depth of 400 miles as an approach to average , though in some cases 1000 miles might be nearer . That the spots are most frequently sunk below the photosphere , as Wilson long since asserted , can no longer be doubted , since Mr. De la Rue , Mr. Stewart , and Mr. Loewy have recorded , after many measures of photographs taken at Kew , as the general result that the interior parts of the solar spot are sunk below the general surface ? . . The spot now under consideration approached the edge of the disk on the 15th of February , when the umbra seemed nearly bridged across by a lighter part , and was perceptibly but very slightly nearer to the following , or left-hand side . The reappearance of this spot was anxiously looked for . It came into view on the morning of March 3 , having when observed passed the limb about 6§ 16 ' . Its appearance was sketched on this occasion , and again on successive days to the 14th of March . Its apparent magnitude was diminished , but the main features were less altered than is usual with sunspots . The umbra still appeared in such relation to the penumbral border as to confirm the opinion of its being but very little depressed below the photosphere . Remarkable changes happened between the 7th and 10th of March . On the 8th two broad penumbral extensions appeared ; on the 9th these were separated into two detached masses , and much altered in figure . Diagram No. 2 . The path of spot A in February and March . The great spot , or rather aggregation of spots , marked C , was observed from the 13th to the 24th of February , as often as good opportunities occurred in the extremely variable weather . When fully expanded , about the 17th , 18th , and 19th of February , it measured about 12 ? on the surface of the sun , and occupied a space about 100,000 miles long , lying not quite parallel to his equator , and including forty or more black , dark , and dusky umbral tracts , in a cormplicated penumbral area . The definition was often excellent , so as to show the granular surface of the photosphere with more than ordinary distinctness . The same fine brown tint already referred to was observed in the penumbral spaces , and there was every gradation of depth in this tint observable in the many specks and spots , till in a few only it seemed to be black . The penumbral tracts were plainly broken up into a kind of network of granllation ; and the largest spot , chosen for special study , threw out long black digitations into the surrounding granulated space of the penumbra , like slits in a solid substance , 1000 or 2000 miles in length . These characters of the largest spot in the group C became very prominent on the 19th of February , and were accompanied by others of an unusual character , which seem to deserve special attention in the question of the nature and history of these black spaces . In the drawing for this date these appearances are sketched with a power of 135 . The spot was somewhat rhomboidal , the extreme length from angle to angle being about 15,000 miles , the least breadth about 4500 . On the right the boundary was gently convex ; parallel to it was a bright facular tract of uniform breadth ; this was margined on the right by a nearly continuous very narrow black band , 17,500 miles long , extending in both directions beyond the spot , and slightly ramose in the ( apparently ) upper part . Parallel to this again was a curiously interrupted series of black angularly bent sharp cuts , ending upwards in a larger subdigitated mass , near which were some other small spots , forming broken chains , which turned off in curves to the right for about 40,000 miles ( P1 . II . fig. 7 ) . On the 20th of February the appearances had changed to those represented in another sketch ( P1 . II . fig. 8 ) , where the great spot , something reduced in magnitude and altered in figure , shows very long digitations on all sides ; the facular space on the right is broader ; the long very narrow black band shows two internal extensions ; the outer crested ridge has gathered itself into a shorter figure , 10,000 miles long , and has lost the character of angular tegulation which was so remarkable on the 19th. . On the 21st the spot had approached enough toward the limb to undergo some apparent change of general figure , by contraction perpendicular to the edge ; the facular space on the right was entirely free from the narrow curved black divisional band ; and the summit of the outer broader band was bent away from the great spot , to which it had been parallel ( PI . II . fig. 9 ) . The disappearance of the spot amidst large elevated bright faculm and depressed broader shaded tracts , was sketched on the 24th of February . Reappearing with similar splendid companion ridges of mountainous clouds , but much reduced in size , and altered in every part , it was observed again from the 12th to the 17th of March , after which the weather allowed no further opportunity . Two sets of drawings of this remarkable spot are presented to show its growth , development , and decay ( P1 . II . figs. 7 , 8 , 9 , and 10 , 11 , 12 ) . The apparent path on the sun 's disk is given for each period of appearance the two paths differing by reason of the change in the apparent place of the sun 's equator ( see Diagram No. 3 ) . Diagram No. 3 . 4 But few examples occur of such large penumbral tracts grouped about so many dark and half-darkened umbrm . On the sun they occupied , as already stated , a tract about 12 ? in length , not quite parallel to the equator ; and may be compared to some of those which are most conspicuous in Mr. Carrington 's plates . From what has been observed , it appears that , in a given zone of spots , not only are the aspects of the particular spots much diversified , but further , that the changes to which they are subject offer much variety . These circumstances seem to point to particular local conditions as the cause of the diversity of appearance , though it may be possible to refer to other influences the frequency of their occurrence , if not the fact of their occurring at all . The five spots now under review lie within an arc of longitude of 205 ? , leaving 155 ? in which as yet no spot has lately been s ? .en . In 1864 , during the months of March and April , a zone of spots , also five in number , and on the same side of the equator , was contained within an arc of longitude of 243 ? , leaving 117 ? at that time free from spots . There was then within the same arc of 243 ? a pair of spots in about the same latitude , but in the opposite hemisphere . Taking these into account , the average of the arcs of longitude between the spots was about 49 ? . In the case of the spots lately passing it was 51 ? . Twenty-six revolutions would have brought the middle of that zone of activity of 1864 to nearly the same place on the sun 's disk , as the group now under consideration . To whatever cause we may ascribe the fact of the breakixng out of these [ Mar. 22 , spots , there would appear reason for expectation that spots of like character may be expected to recur again in the same parts of the sun 's surface . In the great work of Mr. Carrington we find several examples of the appearance of new spots in nearly the same places as those which had been so occupied before . Those who think with M. Chacornac that sun-spots are due to volcanic eruptions , and regard their changes of appearance as effects of the displacement of solid and gaseous bodies about the region of disturbance , must naturally look for repetitions of these phenomena in the same parts of the solar surface . The greater frequency of spots between the parallels of 10 ? and 30 ? lat. N. and S. , the comparative rarity of them on the equator , and the almost entire absence of them from the circumpolar regions is well established . If we take the data from Mr. Carrington 's register and suppose in all 1000 spots to be observed , 178 will be found between the parallels of 0 ? and 10 ? from the equator , 450 between 10 ? and 20 ? , 324 between 20 ? and 30 ? , and 48 above 30 ? . The proportionate numbers for the northern and southern hemispheres are 450 in North latitude , 550 in South latitude . If now we inquire , by the aid of the same invaluable book , as to the relative frequency of spots in different longitudes , we shall obtain a result of considerable interest in reference to the qcuestion of the place of the eruptions . Mr. Carrington has registered his observations through 99 rotations , and has arranged them in groups which can be tabulated for longitude . Assumring the rotation-period to be exact enough for fixing the longitudes in the course of seven years and 142 days , we may represent the relative frequencv of the spots on different meridians as follows : 00 Longitude 10 to 20 ... . 320 maximum ; G , 60 to 70 ... . 220 mini-mui m ; , , 100 to 110 ... . 313 maximum , , 60 to 170 ... . 250 mininmumn ; , 190 to 200 ... . 366 maximum ' 300 to 310 ... . 173 minimumn ; showing three maxima at intervals of 90 ? , 90 ? , and 180 ? , and three minima at intervals of 1000 , 1400 , and 120 ? . Or if we take the eircumference of the sun in three meridional compartments of 120 ? each , and suppose ] 000 spots in all , we shall find 0 to 120 ... . 357 120 to 240 ... . 368 240 to 360 ... . 274 I am at present of opinion that this result may be trust ( so far as to show that certain tracts of the sun 's surface are more liable to eruption than other tracts , by reason of local peculiarity only . 67 Luminosity of the Sun . Attentive observation shows the light of the sun to be feeblest toward the edges of the disk , strongest about the centre . By M. Chacornac 's measure the ratio of the central to the marginal light is 100 to 45 . Looking directly on the central regions , the light is found to be much the brightest on the apparent summits of the undulations of the photosphere ( " ricegrains " ) ; and looking to the limb , it is the facule which are the brightest parts . In each case it is the outermost parts of the photosphere which are the brightest , and it is the innermost parts which are the darkest . The depth of shade appears to be in direct proportion to the depth below the outer surface of the photosphere . It appears to me that such appearances would follow naturally from the hypothesis mentioned in my first communication on this subject * . The hypothesis is that the lowest parts of the umbral spaces yield the least refrangible and least luminous rays , such as belong to the space about the red end of the spectrum . These spaces may not be black , not even very dark , except by comparison with the brilliant spaces around ; where the rays from them pass into the photosphere , they heat it , as the dark rays separated by sulphuret of carbon in Tyndall 's experiment heat the platinum foil , and other solid bodies . Bodies thus heated emit new rays according to their nature ; the solar photosphere is of such a nature as to send to us the miugled pencils which we receive ; the principal effect of this kind being at a maximum on the outermost layer . The effect of this will be to cause streams of the most luminous rays from the most elevated parts of the photosphere , which will be seen directly in front , about the sun 's centre , while toward the edges the sides of the undulations alone will be seen , and the rays which they yield will be less luminous the only parts which are there very bright being the high ridges of the facule . Another view has presented itself to me . If we admit the depressed part to be the body of the sun disclosed from below the luminous envelope , we may suppose its darkness to be due simply to radiation . For however hot the sun may be , if its composition be like that of the earth , the fused parts would be cooled and darkened at the surface where it may be uncovered-very much darkened where the exposure is complete ( the umbra ) , partially so where the envelope is not wholly removed ( the penumbra ) . It might be some test of this view , if the hourly changes of the umbra , immediately after its first appearance , could be accurately noted in respect of the degree of darkness as well as of the change of form . The umbra ought to grow darker and darker , never lighter and lighter , except by the overspreading of photosphere , which would be indicated independently by changes on the penumbral area . From what I have seen in the course of these observations , I infer that the study of the physical condition of the solar spots cannot be regarded as likely to yield data of sufficient weight , if it do not include determina* Proc. Roy . Soc. January 1865 . [ Mar. 22 , tions at short intervals , as twice a day for the whole penumbral outline , and once an hour for selected critical parts of the umbra . EXPLANATION OF PLATE II . [ The figures are all drawn to represent the objects as they appeared in a 6-inch achromatic furnished with the glass mirror set to reflect the rays in the equatorial plane to the westward . The motion of the spot is from left to right . ] Fig. 1 . Appearance of the spot A , nearly on the central meridian , on Feb. 10th , 1866 , at 11h 15im . The darkest part of the umbra was to the right ; on the left a sharp excurrent part like a fissure ; between this and the larger and darker part was a lighter brown tract . Small dots on the penumbra in the upper part to the left . Diameter 23,000 miles . Fig. 2 . First sketch of the spot A after its reappearance , March 5th , 10oh 30 . The long excurrent parts at the extremities of the elliptical figure ( elliptical by reason of the proximity of the spot to the edge of the disk ) are frequent appearances in this position of the spots . This figure is rather too small in proportion to 4 , 5 , and 6 . Fig. 3 . Spot A , further on the disk . The figure is rather too small . Note the peculiar shapes of the small fissure-like extensions on the left . March 6th , 211 30 " . Fig. 4 . Spot A , still further on the disk , March 7th , 10h Om . The ramifications from the umbra have changed in appearance . Fig. 5 . Spot A. near the central meridian , March 8th , 12h 30 " . The two extensions of the penumbra on the left have come into sight since yesterday . Note the little dot at their common origin , and , directed towards it , the longest of the excurrent umbral fissures . Fig. 6 . Spot A , March 9th , 121 0o " . Here the excurrent penumbral tracts are foundc to be separated from the spot , and from each other , and changed in directioni The umbra is much altered , and has a deep emargination , in place , apparently , of a small white speck , seen in fig. 5 . Note also a black speck on the right upper edge of the umbra . Fig. 7 . Spot C , the largest umbral tract with its border on the right , Feb. 19th , 10h 45"1 . On account of the remarkable aspect which the umbra wore on this occasion , it was drawn repeatedly with great care . Note in particular the digitations of the large umbra , the broad facular space to the right , and the parallel very narrow , interrupted , and tegulated umbral bands , which are part of a system of interrupted small dark tracts , traceable through nearly all the length of the penumbra , which on this occasion was about 100,000 miles from end to end . The umbra itself measured about 15,000 miles between the extremities of the digitations . Fig. 8 . The same parts as they appeared on Feb. 20th , 10h 20m . The general figure of the umbra is changed ; the long parallel narrow black space , and the broader tract on the outside of it are greatly altered ; the latter , turning away from the umbra , appears to have gathered into itself the detached spots which appear in fig. 7 , and to have lost the angular tegulation which then was conspicuous . Fig. 9 . In this figure the approach toward the edge of the sun is sensible in the elongation of the large umbra and its com panion . Feb. 21st , 21 30Om . Fig. 10 shows the reappearance of this spot C , near the edge , with a divided umbral tract , of different shades of darkness ; the whole figure compressed elliptically by proximity to the edge . March 12th , 12h 10 . Fig. 11 . The same spot after it had proceeded on the disk , so as to allow of all parts being seen in their true proportions . March l3th , 2'1 30m . The change of figure in the whole penumbral space , and in the darkest parts , is so great that it is difficult to be assured of the identity of any one point now visible with the appearance shown on ally occasion in February . Yet , in fact , on searching carefully the neighbouring tracts of photosphere , we can discern what appear to be traces of the spaces occupied by the old penumbra . This important observation was made , not by myself only , but also by friends who were quite unaware of the interesting changes of form which had occurred . Fig. 12 . March 14th , I11 30m . HIere the spot is seen further modified ; gathered up into a smaller and more regular shape , with a deep slit through the penumlbra into the umbra ; the detached penumbra on the left was lost after a further day 's motion .

112590

3701662

On Uniform Rotation. [Abstract]

71

73

Proceedings of the Royal Society of London

C. W. Siemens

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112590

http://www.jstor.org/stable/112590

Measurement

Fluid Dynamics

Measurement

I. " On Uniform Rotation . " By C. W. SIEMENS , F.R.S. Received March 10 , 1866 . ( Abstract . ) The paper sets out with an inquiry into the conditions of the conical pendulum as a means of obtaining uniform rotation . This instrument , as applied by Watt to regulate the velocity of his steam-engines , is shown to be defective , -first , because the regulated position of the valve depends upon the angular position of the pendulums , and therefore upon the velocity of rotation , which must be permanently changed in order to effect an adjustment of the valve ; and secondly , because when the balance between force and resistance of the engine at a given velocity is disturbed , the angular position of the pendulums will not change until a power has been created in them , through acceleration of the engine , sufficient to overcome the mechanical resistance of the valve , giving rise to a series of fluctuations before a balance between the power and resistance of the engine is reestablished . These defects in Watt 's centrifugal governor are shown to be obviated in the chronometric governor , an instrument which was proposed by the author of the paper twenty-three years ago , and which consists of a conical pendulum proceeding at a uniform angle of rotation , and therefore at uniform speed , which is made to act upon the regulating-valve by means of a differential motion between itself and the engine to be regulated , which latter has to accommodate itself to the rotations imposed by the independent pendulum . The differential-motion wheels are taken advantage of for imparting independent drivingor sustaining-power to the pendulum ; and a constancy of the angle of rotation , notwithstanding unavoidable fluctuations in the sustaining-power , is secured ( within certain limits ) by calling into play a break , or fluid resistance , at the moment when the angle of rotation reaches a maximum , which maximum position is perpetuated by increasing the sustaining-power beyond what is strictly necessary to overcome the ordinary resistance of the pendulum . The chronometric governor is used by the Astronomer Royal to regulate the motion of the large equatorial telescope and recording apparatus at Greenwich , in which application a very high degree of regularity is attained ; but the instrument proved to be too delicate in its adjustments for ordinary steam-engine use . After a short allusion to M. Foucault 's governor , the paper enters upon the description of a new apparatus which the writer has imagined for obtaining uniform rotation , notwithstanding great variations in the drivingpower , and which consists , in the main , of a parabolic cup , open at top and bottom and mounted upon a vertical axis , which cup dips with its smaller opening into a liquid contained within a casing completely enclosing the cup . It is shown that a certain angular velocity of the cup will raise the liquid ( entering from below ) in a parabolic curve to its upper edge or brim , and that a very slight increase of the velocity will cause actual overflow , in the form of a sheet of liquid , which , being raised and projected against the sides of the outer chamber , descends to the bath below , whence fresh liquid continually enters the cup . Without the overflow scarcely any power is required to maintain the cup , with the liquid it contains , in motion ; but the moment an overflow ensues , a considerable amount of power is absorbed in raising and projecting a continuous stream of the liquid , whereby further acceleration is prevented , and nearly uniform velocity is the result . When absolute uniformity is required , the cup is not fixed upon the rotating axis , but is suspended from it by a spiral spring , which not only supports its weight , but also transmits the driving-power by its torsional moment . The cup is guided in the centre upon a helical surface , which arrangement has for its result that an increase of resistance or of driving-power produces an increased torsional action of the spring , and with it an automatic descent of the cup , sufficient to make up for the thickness of overflow required to effect the readjustment between power and resistance , without permanent increase of angular velocity . It is shown that the density of the liquid exercises no influence upon the velocity of the cup , which velocity is expressed by the following formula , p2 n-2r7r in which n signifies the number of revolutions per second , h the height of liquid from the surface to the brim of cup , r the radius of the brim , and p the radius of lower orifice of cup ; only the rigidity of the spring must be greater when a comparatively dense liquid is employed . In order to test the principle of action here involved , Mr. Siemens has constructed a clock consisting of a galvanic battery , an electro-magnet , and his gyrometric cup , besides the necessary reducing-wheels and hands upon a dial face , which proceeds at a uniform rate , although the driving-power may be varied between wide limits , by the introduction of artificial resistances into the electrical circuit . The instrument appears , therefore , well calculated for regulating the speed of all kinds of philosophical apparatus , and also for obtaining synchronous rotations at different places for telegraphic purposes . One of its most interesting applications is embodied in the " Gyrometric Governor " for steam-engines , of which an illustration is given . This consists of a cup of 200 millinetres diameter and the same height , which is fixed upon its vertical axis of rotation , and is enclosed in an outer chamber , containing water in such quantity that the lower extremity of the cup dips below its surface . The upper edge of the rotating cup is , in this application , surrounded by a stationary ring armed with vertical vanes , by which the overflowing liquid is arrested and directed downward , causing it to fall through a space or zone which is traversed by a number of radial and vertical blades projecting from the external surface of the rotating cup , which , in striking the falling liquid , project it with considerable force against the sides of the outer vessel , at the expense of a corresponding retarding effect on the cup , increasing its regulating-power . The cup-spindle carries at its lower extremity a pinion , which gears into two planet-wheels at opposite points , which on their part gear into an inverted wheel surrounding the whole , which latter is fastened upon a vertical shaft in continuation of the cup-spindle , and is driven round by the engine in the opposite direction to the motion of the cup . The two intermediate or planet-wheels are attached to a rocking frame supported , but not fixed , upon the central axis , which wheels , in rotating upon their studs , are also free to follow the impulse of either the pinion or the inverted wheel to the extent of the differential motion arising between them . The rocking frame is connected to the regulating valve of the engine , and also to a weight suspended from a horizontal arm upon the valve-spindle , tending to open the valve and at the same time to accelerate the cup to the extent of the pressure produced between the teeth of the planet-wheels and the pinion , while the engine is constantly employed to raise the weight and to cut off the supply of steam . The result is that the engine has to conform absolutely to the regular motion imposed by the cup , which will be precisely the same when the engine is charged with its maximum or its minimum of resisting load . The paper shows that the action upon the valve must take place at the moment when the balance between the power and load of the engine is disturbed , and that the readjustment will be effected notwithstanding a resistance of the valve exceeding 100 kilogrammes-a result tending towards the attainment of several important objects .

112591

3701662

On a Fluorescent Substance, Resembling Quinine, in Animals; and on the Rate of Passage of Quinine into the Vascular and Nonvascular Textures of the Body

73

93

Proceedings of the Royal Society of London

H. Bence Jones|A. Dupr\#xE9;

fla

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112591

http://www.jstor.org/stable/112591

Physiology

Chemistry 2

Physiology

Professor Donders has carefully investigated the time in which atropine and Old Calabar bean begin and cease to act on the iris in man . A solution of atropine dropped upon the cornea began to act in fifteen minutes , and attained its maximum in from twenty to twenty-five minutes . In forty-two hours the pupil was rather smaller ; and even after thirteen days the pupil had not returned to its natural size . The solution of Calabar bean began to act in from five to ten minutes . It attained its maximum in from thirty to forty minutes . At the end of three hours it began to diminish , and its effect disappeared entirely in from two to four days . After continued applications of belladonna to the eye of a rabbit , it was thoroughly washed by a full current of water . The aqueous humour was then evacuated and brought into contact for a long time with the eye of a dog ( De Graefe injected the aqueous humour into the anterior chamber ) ; then a notable dilatation of the pupil was observed . As one part in 120,000 of water acts very energetically , the quantity must be very little that produced the dilatation of the pupil . When belladonna used internally produces the dilatation , the aqueous humour which is taken from the anterior chamber is inactive . Thirdly . The fluorescence that naturally occurs in different parts of the human body when no quinine had been taken before death was determined , in order that the effect of quinine on the fluorescence in the same parts might be estimated : The different parts were dried in a water-bath , and equal quantities of the dried substance were taken , amounting to 0'6 grain , that being the weight of the dry lens . The same method of extraction was followed . The solution was in all cases made up to twenty-five grains . Extract from per 100 litres . Cartilage fluoresced one 32nd of a grain of quinine to a litre. . =3'1 Nerves fluoresced a little more than one 64th of a grain of quinine to a litre ... ... ... ... ... ... ... ... ... ... ... . =1*6 Liver fluoresced a little more than one 64th of a grain of quinine to a litre ... ... ... ... ... ... ... . . =1 6 Kidney fluoresced a little more than one 64th of a grain of quinine to a litre ... ... ... ... . . =16 Lens fluoresced a little less than one 64th of a grain of quinine to a litre ... ... ... . * ... ..l ... ... ... 6 ... ... . 1 ' Lungs fluoresced one 128th to one 64th of a grain of quinine to a litre ... ... ... ... .=0 ... ... ... ... ... . 08 to 1'6 Muscle fluoresced a little more than one 128th of a grain of quinine to a litre ... ... ... ... ... ... ... ... ... ... =.0'8 Spleen fluoresced one 128th of a grain of quinine to a litre. . =0'8 In another patient , who died after a surgical operation , the same quantity of substance , treated in exactly the same way , gave[Apr . 12 , 88 Extract from per 100 litres Cartilage fluoresced a little less than one 128th of a grain of quinine to a litre ... ... ... ... ... ... ... =0'8 Nerves fluoresced a little less than one 128th of a grain of quinine to a litre ... ... ... ... ... ... ... ... . . =0'8 Liver fluoresced a little less than one 64th of a grain of quinine to a litre ... ... ... ... ... ... ... ... ... ... . = -1'6 Kidney fluoresced a little less than one 64th of a grain of quinine to a litre ... ... ... ... = 1'6 Lungs fluoresced one 128th of a grain of quinine to a litre. . =0'8 Muscle fluoresced between one 128th and one 64th of a grain of quinine to a litre - ... ... .=0'8 to 1'6 Spleen fluoresced a little less than one 128th of a grain of quinine to a litre ... ... ... . ; ... ... ... ... ... ... ... . . =08 Heart fluoresced one 128th of a grain of quinine to a litre. . =0'8 When a much larger quantity of each organ was taken ( whether from loss or destruction of substance in the process of preparation ) , no great increase of fluorescence was obtained . Thus , of the different parts of a man who died of apoplexy , six grains were taken and treated as in the previous cases . Extract from per 100 litres . Cartilage fluoresced one 128th to one 64th of a grain of quinine to a litre ... ... ... ... ... ... ... ... ... ... ... . =08 to 1'6 Nerves fluoresced one 64th of a grain of quinine to a litre. . 1'6 Liver fluoresced one 64th of a grain of quinine to a litre ... . = 1'6 Kidney fluoresced one 64th to one 32nd of a grain of quinine to a litre ... ... ... ... ... ... ... ... ... ... =1'6 to 3'1 Lungs fluoresced one 64th of a grain of quinine to a litre. . =1'6 Muscle fluoresced a little less than one 64th of a grain of quinine to a litre ... 6 ... ... ... ... ..= 16 Spleen fluoresced one 64th to one 32nd of a grain of quinine to a litre ... ... ... . . =16 to 31 Heart fluoresced one 32nd of a grain of quinine to a litre. . =3 1 Brain fluoresced one 64th to one 32nd of a grain of quinine to a litre ... ... ... ... ... . = 1-6 to 3-1 In a precisely similar way the different parts of the tissues of a woman who had taken small doses of quinine up to twenty-four hours of her death , were examined . The tissues were dried in a water-bath , and 0'6 grain of the dry substance was taken for examination . Extract from per 100 litres . Kidney fluoresced one 32nd to one 16th of a grain of quinine to a litre ... ... ... ... ... -- , ==3'1 to 6'3 I Nerves fluoresced a little more than one 64th of a grain of quinine to a litre ... .= ... ... ... ... ... ... ... = 1'6 Liver fluoresced one 64th of a grain of quinine to a litre ... . =1 ' 6 Muscle fluoresced one 64th of a grain of quinine to a litre. . =1'6 Spleen fluoresced a little less than one 32nd of a grain of quinine to a litre ... ... ... ... ... ... ... ... ... . =31 Lungs fluoresced one 128th to one 64th of a grain of quinine to a litre ... ... ... ... ... .=08 to 1-6 Fourthly . On the increase of fluorescent substance in the human lens after different quantities of sulphate of quinine had been taken at different periods before the operation for cataract ( for the means of making these experiments we are indebted td the great kindness of Mr. Bowman):The fluorescence of the human lens without cataract was about equal to one 64th of a grain of quinine in a litre of water ; grs. per 100 litres . That is , natural fluorescence about ... ... ... ... ... ... . . 1'6 Sulphate of quinine was given for many days previous to the extraction of a cataract . After the operation the fluorescence was found to be less than one 16th and more than one 32nd of a grain of quinine to a litre of water ... ... =c6'2 to 3'1 In four patients , aged respectively 75 , 60 , 60 , and 72:the lens removed 1 hour after 5 grains of quinine , fluorescence =1 6 , , 14 , , , , =1'6 , 2 , , =1-6 2 , , 2 , , =-21 to 1-6 Fifthly . On the rate of increase of fluorescent substance in the urine after quinine was taken , or on the rapidity of the passage of quinine , when taken by the stomach , into and out of the urine of man : A healthy man breakfasted at 8.30 A.M. ; at 12 he emptied the bladder , and took four grains of sulphate of quinine in solution . The fluorescence of the urine at different periods after the quinine was taken was examined by rendering it alkaline with caustic potash and shaking it up three times with its own bulk of ether . Half an ounce of urine was taken for each examination . Urine passed at gr. of quinine . water . 12 ( just before taking the quinine ) , fluorescence=ie --to -4 to 1 litre . 12.10 , fluorescence ... ... ... ... ..= , 12.20 , , ... ... ... .= to , , 12.30 = 4to4 , , 12.30 , , ... ... ... ... ... ... ... to 1 ... ... ... ... ... ... ... . to 2 ... ... ... ... ... ... = tol 4 , , ... ... ..o ... ... ... ... ... t , 8 , . 8 24 hours after quinine , fluorescence ... ... ... little less . 48 , ... ... ... . , little more . 72 , , , ... . about 1 ? , [ Apr. 12 , 90 The same man breakfasted at 8.30 A.M. ; at 12 took four grains of sulphate of quinine . Urine passed at gr. of quinine . water . 12 ( just before taking the quinine ) , fluorescence -= to to 1 litre . 12.10 , fluorescence ... ... ... ... ... ... ... . to ~~1 ~~~2 . ~~-20 , * Urine passed at . gr. of quinine . water . 12.30 , fluorescence below ... ... ... ... ... ... . . to 1 litre . 1 , ... ... ... ... ... ... . . I to i2 , , , ... ... ... ... ... ... . . ? to 1 , , 4 , , , ... ... ... ... ... ... . . to , , , ... ... ... ... ... ... . . to , , 24 , , , ... ... ... to 11 48 , ... ... ... ... ... ... . . I e , 72 , , , ... . . scarcely perceptible . The same boy breakfasted at 8.30 , passed urine at 12 noon , and immediately took four grains of sulphate of quinine . The fluorescence was observed in half an ounce of the urine passed at different periods after the quinine was taken . Urine passed at gr. of quinine . water . 12 ( just before taking the quinine ) , fluorescence 1 - , little more , to 1 litre . 12.15 , fluorescence ... ... ... ... ... ... ... y to 12.30 , , , ... ... ... ... ... ... ... . 1 1 , , , ... ... ... ... ... ... above 1 , , 2 , , ... ... ... ... ... ... above 1 , 3 , , , ... ... ... ... ... . . above I ( was at maximu ) , , 4 , , ... ... ... ... ... ... .above 1 8 , , , ... ... ... ... ... ... . . 1 24 , , ... ... ... 48 , ... ... ... ... ... ... ... . to 72 , , , ... ... ... ... ... ... ... not perceptible . Henlce in fifteen minutes quinine is detectable in the urine , and in three hours the maximum quantity is present in the urine . In eight hours it begins to decrease ; in forty-eight hours it is much decreased ; and in seventy-two hours it has entirely disappeared . CONCLUSIONS . Part I. From every texture of man and of some animals a fluorescent substance can be extracted , which is identical with the fluorescent substance that for some years has been known to exist in the lenses of man and animals . This fluorescent substance , when extracted , has a very close optical and chemical resemblance to quinine , and when mixed with quinine it cannot be separated from it ; we have therefore called it " animal quinoidine . " Part II . By quantitative determinations of the amount of fluorescent substances naturally existing in the textures , we were able to determine the rate and time of increase of fluorescent substance in the vascular and non-vas . cular textures of animals , and in the urine of man after quinine had been taken . By this means we have shown that in guineapigs , in fifteen minutes , the quinine has certainly passed into all the vascular , and most probably into the extra-vascular textures . In three hours the amount of quinine in the textures may be at the maximum ; and for six hours it does not much diminish . In twenty-four hours the quinine sinks very considerably , and in forty-eight hours it is scarcely perceptible anywhere . By similar experiments on cataracts in man , it appears that in two hours and a quarter traces of quinine may be found in the lens . After quinine has been taken , it begins to appear in the urine in from ten to twenty minutes ; in from two to three hours it has reached its maximum ; in from three or four , or at longest eight hours , it begins to decrease ; in twenty-four hours it has very much decreased ; in fortyeight hours its presence is still detectable ; but in seventy-two hours not a trace of it can be found . II . " On a Fluorescent Substance , resembling Quinine , in Animals ; and on the Rate of Passage of Quinine into the Vascular and Nonvascular Textures of the Body . " By H. BENCE JONES , M.D. , F.R.S. , and A.DUPR33 , Ph. D. , F.C.S. Received March 14,1866 . PART I. On a Fluorescent Substance , resembling Quinine , in Animals . The term fluorescence in the last few years has found a place in physiological works because different substances that occur in the body have been said to possess the property of fluorescence . Of these the solution of bileacids in concentrated sulphuric acid , the white of egg when kept for a H2 73 short time , and the urine sometimes , are the best-known fluorescing substances . But as long since as 1845 , Professor Briicke , in Miiller 's Archiv , ' stated that he had found in many and very frequently repeated experiments , that the lens absorbed the blue rays of light to a very great extent , and that the cornea and the aqueous humour did so to a less extent , but that the lens together with these other media absorbed these rays to the greatest degree . He used the eyes of oxen and of rabbits , and the lens of a pike 's eye , which last , when dried with care , preserved its transparency , and allowed the light to fall on a porcelain plate covered with tincture of guaiacum and bleach a portion of the green surface . Professor Stokes , in his well-known paper " On the Change of the Refrangibility of Light , " in the Philosophical Transactions for 1852 , says ( p. 512 ) , " It is found that the property of change of refrangibility in the incident light is extremely common . " " To make a list of sensitive substances would be useless work ; for it is very rare to meet with a white or light-coloured organic substance which is not more or less sensitive . " Among others he mentions horn , bone , ivory , white shells , leather , quills , white feathers , white bristles , the skin of the hand , and the nails . And in his conclusion ( p. 557 ) , he says , " The phenomenon of change of refrangibility proves to be extremely common , especially in the case of organic substances , such as those ordinarily met with , in which it is almost always manifested to a greater or less degree . " When speaking of the fluorescence of sulphate of quinine , he says ( p. 541 ) , " When quinine was dissolved in dilute hydrochloric acid , the blue colour was not exhibited , not even when the fluid was held in the sunlight and examined by superficial projection . " In 1855 Helmholtz published a paper in Poggendorff 's 'Annalen , ' vol.xciv . p. 205 , in which he says that , as far as quinine paper showed that the spectrum extended , so far the eye could perceive light * . He then proposes this question , Does the retina see the rays beyond the violet directly as it sees other colours of the spectrum , or does it fluoresce under the influence of these rays ? and is the blue colour of the rays beyond the violet light of less refrangibility which shows itself in the retina only under the influence of the violet rays ? To determine this question , he says , I examined for fluorescence the retina of the eye of a man who had been dead for eighteen hours . The first experiment showed that it was very feebly fluorescent . The retina was less fluorescent than paper , linen , and ivory , but more than porcelain . The colour of the light dispersed through the retina is greenish white , very different from that which the direct perception of these rays usually gives . In 1858 , in the Comptes Rendns des Seances de la Societe de Biologie pendant le mois de Novembre 1858 , pp. 166 & 167 , there is a short notice headed " Analyse et conclusions d'un travail sir la fluorescence des milieux de l'ceil , par M. Jules Regnauld . " He used sunlight , and found in man and the mammifera that the cornea fluoresced in a very slight degree . In the sheep , dog , cat , and rabbit , the crystalline lens possessed in the highest degree fluorescent properties . In these animals , and also in many birds , the central part of the lens ( endophaine of MM . Valenciennes and Fremy ) , preserved by desiccation at a low temperature , retained this property . The central portion of the crystalline of many aquatic vertebrata and mollusca ( phaconine of MM . Valenciennes and Fremy ) is almost entirely without fluorescence . The hyaloid body possesses only a very feeble fluorescence , due to the hyaline membranes ; for the vitreous humour itself is not fluorescent . The retina , as M. Helmholtz discovered , possesses a certain fluorescence which is not at all comparable in intensity to that of the crystalline lens of mammifera . Finally , M. Regnauld concludes that , if we must attribute the accidents caused by feebly luminous radiations of the electric light to the phenomena of fluorescence , it is above all in the energetic action on the crystalline that it is natural to look for an explanation . The impression which the cornea undergoes must nevertheless not be neglected . In 1859 , in the 'Archiv fur Ophthalmologie , ' vol. v. part 11 . p. 205 , there is a paper by J. Setschenow of Moscow , " On the Fluorescence of the Transparent Media of the Eyes of Man and some other Animals . " He undertook the examination at Professor Helmholtz 's request , because it was possible that the phenomena of fluorescence observed by Helmholtz might have been modified by a post-mortem change in the eye . He experimented on the eyes of oxen and rabbits . The fresh retina showed the same phenomena as the dead human retina . It diffused a greenish-white light , which , examined by a prism , gives a spectrum in which the red is wanting . The vitreous humour in a thin glass vessel showed only traces of fluorescence . The lens , on the contrary , fluoresced very strongly : the colour of the dispersed light is white-blue , exactly like quinine ; only the quinine was a little stronger . Examined by a prism , the dispersed light gave a spectrum in which the red was wanting , and in which the blue tone predominated . The fluorescence begins , as in quinine solutions , between G and H , and is strongest at the outer edge of the violet rays , and extends into the ultraviolet to the same distance in the case of the lens as in the case of the quinine solution . 75 1866 . ] When the cornea was cut out , it fluoresced much feebler than the lens ; the aqueous humour did not fluoresce at all . The appearances in the three last media , he says , can be shown with the greatest ease , even in the eye of a living man . When the eye is brought into the focus of the ultra-violet rays , immediately the cornea and the lens begin to glimmer with a white-blue light . The cornea in the living eye is much more strongly fluorescent than when dissected out , probably from the loss of transparency consequent on contraction of the texture and from evaporation . The question how and why our eyes perceive the ultra-violet spectrum is still undetermined . The fluorescence of the lens would be rather a hindrance than a help ; only the general sensibility to the light which the ultra-violet rays produce in our eyes can be explained by the fluorescence of the media lying before the retina . In 1862 , ' Zeitschrift ffir Rationelle Medicin , ' 3rd series , vol. xiii . p. 270 , Pfluger , by mixing fresh ox-gall with concentrated sulphuric acid , saw a clear dichrotic solution form . It had a deep red colour by transmitted light , and a beautiful green colour by reflected light . This was seen very beautifully when dried bile was put into sulphuric acid ; and then the dichroism increased by standing . It is desirable to separate the cholesterin and the bile-fats . The green fluorescence appeared when only blue or green light fell on the sulphuric-acid solution of the bile . On the contrary , it did not appear when the light was only yellow or red . The sulphuric-acid solution of the bile absorbed all the rays of the spectrum except the yellow and the red . In the ' Journal fiirPrakt . Chem. ' vol. xcii . p. 167 , Schonbein has the following remarks on the formation of a fluorescing substance in the putrefaction of human urine : If urine is left to stand in the air until it becomes covered on the surface with a thick layer of fungus , the alkaline fluid that filters from it shows a very strong fluorescence of a greenish colour . Small quantities of the stronger organic or inorganic acids take away this fluorescence , which , however , by alkalies can be again reproduced . This substance has a reaction like esculine , and , like this , is the opposite to quinine , the fluorescence of which is increased by those acids . The hydrobromic , hydriodic , and hydrochloric acids lessen the fluorescence of the solution of quinine almost to entire removal . Schonbein also remarked that fresh urine had a feeble fluorescence , and also that a weak solution of albumen , by standing long in the air , became fluorescent to a considerable degree . This was the state of our knowledge of fluorescence in animals when , having traced the rate of passage of chloride of lithium and other mineral substances into and out of the textures by means of the spectrum analysis , we endeavoured to find some method of determining the rate at which organic substances passed into and out of the same structures . 76 [ Apr. 12 , Among all the delicate tests for different organic substances , the fluorescence of sulphate of quinine appeared likely to afford good results ; for the following experiments on the delicacy of this test for sulphate of quinine show that this method of tracing sulphate of quinine into and out of the body , though inferior to the spectrum determinations of lithium , was superior in delicacy to the spectrum determinations of many other substances . On the Delicacy of the Fluorescent Test of Sulphate of Quinine when a Ruhmkorf coil was used as the source of light . One grain of sulphate of quinine was dissolved in five ounces of acidified water , and this was again and again diluted until one grain of quinine-salt was present in 1,800,000 parts of water . This , when examined in a quartz cell by the induction-spark , showed blue fluorescence distinctly in twenty grains of solution . Another grain , dissolved in a litre and diluted until one grain of salt was present in 1,440,000 parts of water , when acidified , also showed the fluorescence distinctly in twenty grains of solution . The same quantity , dissolved in one litre of water , was diluted to 512 litres . This was equal to one part in 7,200,000 parts of water ; as the fluorescence could be seen in twenty grains of this solution , 36 of a grain of sulphate of quinine gives the fluorescence . In another experiment , 250 of sulphate of quinine , in fifty minims of water acidified , showed the fluorescence strongly , and even 6o , of a grain of sulphate of quinine in fifty minims of water showed the fluorescence feebly . As the fluorescence could be seen in twenty grains of this solution , 20-00 of a grain of sulphate of quinine gives the fluorescence . In the last two sets of experiments the light of a bright induction-spark was concentrated by a small quartz lens . One grain of disulphate of quinine , dissolved in 256 litres of water acidulated with one-eighth of sulphuric acid ( 1 to 8 ) , shows fluorescence feebly in a quartz cell containing twelve grains of the solution . Ience 310grain gives the fluorescence feebly . If one grain of disulphate of quinine is dissolved in a thousand litres , or one part of quinine to 15,440,000 of water , the fluorescence is still perceptible in one ounce of the solution . On the Existence of an extractable Fluorescent Substance in Animals and Man . Immediately on trying to apply this reaction to test the different textures of guineapigs , after and before they had taken quinine , we found that in health no part of any of the tissues of the guineapig was free from blue fluorescence . It became desirable , therefore , to separate the fluorescence produced by some fluorescing substance normally present in the tissues from that produced after quinine was given . After very many attempts to extract these substances separately from the tissues , and many more to separate them when they were conjointly extracted , all of which proved unsuccessful , we resorted to the plan of determining the amount of natural fluorescence by comparing it with standard solutions of sulphate of quinine ; and by the same means we measured the increase that occurred in the amount of fluorescence from the same organs after quinine had been taken . The following plan was adopted for the extraction of the fluorescent substance from the textures , both before and after quinine was taken . The part to be examined was treated on a water-bath with very dilute sulphuric acid , either directly or after previous drying in a water-oven . This extraction was repeated again and again . The acid extracts were mixed , filtered after cooling , neutralized with caustic soda , and repeatedly shaken up with their own bulk of ether . The residue left after evaporation of the ether was taken up by dilute sulphuric acid , filtered , and tested for the amount of fluorescence after having been made up to a certain bulk , generally twenty-five minims . When a large quantity of material , as two or three pounds of liver , was employed , the acid extract was a second time neutralized and treated with ether ; the residue from the second ethereal solution was then taken up with dilute sulphuric acid and tested . In very dilute solutions the fluorescence of the animal substance cannot be distinguished from that produced by quinine ; if the solution is more concentrated , the fluorescence of the animal substance is confined much more to the surface , the fluorescence in a solution of quinine passing much further into the liquid ; and in still more concentrated solutions , the colour of the light given out is of a decidedly greenish hue . The fluorescence also of the animal substance begins to appear somewhat nearer to the red end of the spectrum than is the case with quinine ; but both extend to the same distance beyond the violet end . From two to three pounds of liver , only about fifty minims'of a solution was obtained showing a fluorescence equal to that produced by two or three grains of quinine to the litre of water ; and when slightly acidified , the-following reactions were obtained with the solution . It gives a precipitate with solution of iodine , with a solution of iodide of mercury in iodide of potassium , and also with phosphomolybdic acid , bichloride of platinum , and terchloride of gold : this last precipitate is soluble in alcohol , like that produced in solutions of quinine . A weak solution of quinine interposed in a quartz cell before the solution of the natural fluorescing substance , did not stop the fluorescence of this latter substance entirely ; but when the solution of animal substance was placed before the solution of quinine , no fluorescence whatever could be perceived in the quinine . ]Ether is unable to extract the animal substance from an acid solution ; the acid solution may be shaken up several times with ether ; but the ethereal solution on evaporation yields a residue which , when taken up by dilute sulphuric acid , gives no blue fluorescence whatever . The fluorescence of this animal substance is much less strong in hydrochloric acid solutions by the light of the coil-spark , and it is almost destroyed 78 by alkalies . The substance does not lose its fluorescence when treated with dilute sulphuric acid on a water-bath , nor even on the addition of a dilute solution of permanganate of potash . In an alkaline solution with permanganate of potash it is immediately destroyed . Quinine behaves in a precisely similar way . Parts of the brain , kidney , liver , and heart , and the crystalline lens of a human subject dead for many hours , were boiled with dilute sulphuric acid , neutralized with carbonate of soda , and extracted with ether . The ethereal residue , dissolved in dilute sulphuric acid , was examined by the spark of the Ruhmkorf coil for fluorescence . From every part the extract fluoresced distinctly but very feebly . The fluorescence closely resembled that caused by a very weak solution of quinine . The lenses from sheep 's , bullocks ' , pikes ' , eagles ' eyes , gave a distinctly fluorescent substance , and the extract from the sheep 's liver fluoresced very strongly . Cod-liver oil also fluoresced very distinctly . The so-called pills of cod-liver oil gave no fluorescence . The fluorescent substance could be extracted by treating the finely divided substance with alcohol , and the residue of the alcohol solution by ether , and finally dissolving the ethereal residue in water acidulated with sulphuric acid . It follows from these experiments that there exists in the body of man and animals , fishes , and birds a substance which can be extracted from any of the tissues by the same process as quinine when present can be extracted . This substance has the same reactions with chemical agents as quinine has , and the action of light upon this substance is almost , although not altogether , identical with its action on quinine . This substance is visible in the lens of the human eye during life . It is , from its mode of separation and reactions , an alkaloid bearing a close resemblance in its properties to quinine . For the present we shall call this animal quinoidine . It is the cause of the blue fluorescence of weak acid extracts from any of the tissues of the body of men and animals . When concentrated , the fluorescent substance is bluish green . On the Fluorescent Substance produced by treating Bile with strong Sulphuric Acid . We were unable to insulate and extract the substance which causes the green fluorescence in bile when it is treated with strong sulphuric acid ; nor could we separate that which forms in white of egg when a solution in water is exposed to the air . The bile dissolved in strong sulphuric acid was transparent by transmitted light , and appeared as a brownish-yellow solution ; by reflected light , even with the ordinary gaslight , it showed a strong green fluorescence , in much larger quantity than , and entirely different in appearance from , the blue fluorescent substance of the liver . Thus it was destroyed by diluting the acid with water , but returned on the addition of a larger quantity of strong sulphuric acid . The solution of egg-albumen , exposed to the air , gradually after some days showed a strong green fluorescence , which , like esculine , disappeared on the addition of an acid , but was not destroyed by alkalies . The fluorescence gradually disappeared when the albumen began to putrefy . PART II . On the Increase of Fluorescence in the Textures of Animals and Mcan after Quinine had been taken . Having proved that in all the different textures of an animal a natural alkaloid fluorescent substance was present when no quinine had been taken , and as no means could be found for separating the natural fluorescent substance from the quinine when it passed into the textures , it became necessary to make our analyses quantitative instead of qualitative . For this purpose it was necessary to determine , by means of standard solutions of quinine , what was the greatest amount of naturally fluorescent substance that usually occurred and , could be extracted from the tissues . Deducting this from the amount of fluorescence that could be extracted after quinine was given , we were enabled to measure the rapidity of passage of the quinine into or out of the tissues , the animals being destroyed at different periods after different quantities of sulphate of quinine had been taken . So also by determining the amount of natural fluorescent substance in the textures , lenses , and urine of man before quinine was taken , and deducting this from the amount obtained after quinine was taken , we were enabled to show that quinine does pass into the textures and lenses , and how quickly it appeared in the urine and reached its maximum and began to disappear and entirely vanished . First . Examinations of different textures of guineapigs when no quinine was taken , and comparison of the amount of natural fluorescent substance with standard solutions of sulphate of quinine . The amount of the different parts examined was as nearly as possible always the same : 1 . A guineapig that had taken no quinine was killed ; the extract of the brain and nerves only was measured . The fluorescence of the nerves was very feeble , and about equal to one-twentieth of a grain of sulphate of quinine in a litre of water . The extract of the brain was exceedingly feeble , and it was less than one-thirtieth of a grain of sulphate of quinine in a litre of water . 2 . In another guineapig the lenses and the nerves were dried , and boiled three times with dilute sulphuric acid . The acid solution was rendered alkaline by caustic potass , and it was then shaken up with ether three times . The ethereal solution was evaporated , and the residue dissolved in dilute sulphuric acid . The acid solution was made up to twenty-five minims . The solutions of the lenses and of the nerves showed some fluorescence . These acid solutions were now again rendered alkaline and were shaken up with ether , and the ethereal solution was evaporated and the residue I_ _ _I _ issolved in acetic acid , and the excess of the acid evaporated in a waterbath ; the residue was dissolved in a little water , and the solutions were divided into two parts . The half of the solution from the lenses and nerves , when tested with a solution of iodine and a solution of iodide of mercury , remained perfectly clear . The bile , brain , and liver , tested in the same way , gave no precipitates with these reagents , although they also gave slight fluorescence . The different parts of this pig were compared with the corresponding parts of two other pigs , one of which took sixteen grains of sulphate of quinine in nine doses in four days , and the other twenty-six grains in fourteen doses in six days . 3 . Another guineapig had the different organs treated in exactly the same way ; the liver , lenses , kidneys , urine , blood , brain , nerves , and muscle gave a fluorescence which varied from about one-twentieth to onethirty-second part of a grain of quinine in a litre of water . This pig was bought at the same time and place , and fed in the same way as two other pigs ( 18 and 23 ) , that were given six grains of sulphate of quinine in three doses with twenty minutes ' interval . One pig was killed between five and six hours after the quinine , and the other in twenty-four hours . 4 . Another pig was also treated in the same way , for comparison with three other pigs which took five grains of quinine , and were killed four hours , eight hours , and thirty-two hours afterwards . The lenses , humours , brain , blood , nerves , and muscle gave a fluorescence varying from onetwenty-fifth to one-fiftieth of a grain of quinine in a litre of water . 5 . Another pig had taken no quinine . The brain gave a fluorescence equal to one-thirtieth of a grain of quinine , and the nerves fluoresced equal to one-twentieth of a grain of quinine . 6 . Another guineapig had equal quantities of the liver , bile , kidney , urine , brain , lenses , humours , nerves , blood , and muscle treated in the same.way . The fluorescence obtained from the liver was from one-thirtysecond to one-sixteenth part of a grain of quinine . The fluorescence of all other parts was less than one-thirty-second part of a grain of quinine . The fluorescence of the humours was least of all . 7 . Another guineapig was given no quinine . Equal quantities of dry liver , blood , bile , kidney , brain , nerves , lenses , muscle , and humours were taken . Of the bile and humours , which were taken entire , rather less than half a grain , of the other parts half a grain was used ; the liver fluoresced equal to one-sixteenth of a grain of quinine . The bile , blood , kidney , brain , nerves , lens , and muscle showed somewhat less than one-sixty-fourth part of a grain to a litre ; the humours of the eye rather more than one-sixtyfourth part . 8 . Another pig , bought at the same time and place as 17 , was given no quinine ; and the fluorescence of every part was less than one-sixtyfourth of a grain of quinine in a litre of water . The fluorescence of each solution was rendered still less by the addition of common salt . 81 1866 . ] Secondly . On the increase of fluorescence that was observed when different quantities of sulphate of quinine were given to animals at different periods before they were killed:9 . A guineapig was given sixteen grains of sulphate of quinine , in nine doses , in the course of four days . It was found dead more than twelve hours after the last dose . Its fluorescence was compared with pig 2 , which had taken no quinine ; the lenses and the nerves , treated the same way , showed much more fluorescence in the pig that had taken quinine than in the other which had had no quinine . The solutions of the lenses and the nerves also gave a distinct precipitate , which was least in the solution of the lenses with solutions of iodine and of iodide of mercury ; whilst the solutions of the lenses and the nerves of the pig that had taken no quinine remained clear . The bile and the brain fluoresced brightly . The solution of the liver , when diluted even to one hundred minims , fluoresced distinctly in daylight , and very strongly in the light of the spark . The brain-solution gave a distinct precipitate with iodine and iodide of mercury . The bile gave a very faint turbidity . The liver gave an abundant precipitate , and moreover gave Herapath 's test for quinine very distinctly . 10 . Another pig took twenty-six grains of quinine , in fourteen doses , during six days . It was killed nineteen hours after the last dose , being apparently partially paralyzed . The solutions of the different organs were prepared in the same way as 9 and 2 , and they were examined at the same time . The lenses showed the fluorescence very strongly when a cone of sunlight was thrown into them with a quartz lens . The humours showed no fluorescence at all in this manner . The solutions of the bile , brain , urine , nerves , lenses , spinal marrow , liver , gave more or less distinct fluorescence . The solution of the brain gave no precipitate with iodine or iodide of mercury ; nor did the bile give a precipitate , but the liver gave a slight precipitate with both reagents . Having thus satisfied ourselves that quinine does pass into the vascular and non-vascular tissues , we proceeded to determine how quickly four , five , or six grains of sulphate of quinine given to guineapigs could be detected in the different textures of their bodies . 11 . A guineapig was given four grains of sulphate of quinine , and it was killed in one quarter of an hour ; all the extracts from the different parts of the body were mixed with one-eighth of their bulk of dilute sulphuric acid , and were made up to twenty-five minims . The amount of fluorescence was compared with the fluorescence obtained in pig 6 , and with standard solutions of sulphate of quinine with one-eighth of dilute sulphuric acid , containing one grain , three-quarters , half , one-eighth , one-sixteenth , and one-thirty-second of a grain of sulphate of quinine . The solutions of the extracts of pigs 19 , 22 , 25 , and 26 , which had taken four grains of sulphate of quinine and were killed six hours , twenty-four hours , forty-eight hours , and seventy-two hours after the quinine was taken , were examined at the same time . [ Apr. 12 , The urine and the blood gave a fluorescence equal to half a grain of quinine to a litre of water ; the extract of the kidney and the liver gave a fluorescence equal to three-fourths of a grain of quinine ; the extract of the muscle gave a fluorescence between half a grain and one-fourth of a grain . The extract of the bile and the brain gave a fluorescence nearly equal to one-eighth of a grain of quinine to a litre . The nerves gave rather more fluorescence than one-sixteenth of a grain of quinine , and the lenses gave between one-sixteenth and one-thirty-second of a grain . Comparing these numbers with pig 6 , in which the fluorescence of the liver was greatest , amounting to from one-thirty-second to one-sixteenth of a grain of quinine to a litre of water , whilst in all other parts , urine , blood , kidney , muscle , bile , brain , nerves , and lenses , the natural fluorescence was less than one-thirty-second of a grain , it is evident that in a quarter of an hour sulphate of quinine passes into all the vascular and non-vascular structures of the body . 12 . Another guineapig was given four grains of sulphate of quinine , and it was killed in half an hour ; the nerves and brain were compared with pig 1 , which had taken no quinine . The extract of the liver and kidneys gave a fluorescence equal to two-fifths of a grain of sulphate of quinine in a litre ; the blood , the bile , and the muscle gave a fluorescence equal to onefifth ; the urine gave a fluorescence between one-fifth and one-tenth ; the brain between one-tenth and one-twentieth ; the humours of the eye fluoresced feebly , but a little more than the lenses , about one-twentieth ; the lenses and the nerves less than one-twentieth of a grain of quinine . 13 . Another guineapig took four grains of sulphate of quinine , and was killed one hour afterwards . The blood , the kidney , and the urine gave a fluorescence equal to , or rather more than , one-fifth of a grain of quinine to a litre ; the liver fluoresced equal to between one-fifth and two-fifths of a grain of quinine ; the bile and the muscles gave a fluorescence equal to one-twentieth of a grain of quinine ; the brain fluoresced between onetwentieth and one-thirtieth ; the humours fluoresced rather more than the lenses ; and the nerves gave the slightest fluorescence . 14 . Another guineapig was given four grains of sulphate of quinine ; after three hours it was killed . It had been strongly affected , and the brain was much congested . The liver , kidney , blood , urine , bile , brain , and muscle gave very strong fluorescence , equal to between one and two grains of quinine in a litre of water ; the nerves gave a fluorescence equal to one-sixteenth of a grain of quinine ; the humours gave a fluorescence between one-sixteenth and one-thirty-second part of a grain ; the lenses less than one-thirty-second part of a grain of quinine to a litre of water . 15 . Another guineapig was given four grains of sulphate of quinine ; after three hours it was killed . Of every part half of the dry substance was taken , except the aqueous humour , bile , and urine , of which the whole was taken ; but when dry each of these was less than half a grain . Half the muscle gave a fluorescence equal nearly to one-sixteenth of a grain of quinine in a litre ; half the brain fluoresced a little more than one-thirty-second ; half the kidney one-eighth to one-fourth of a grain ; all the urine oneeighth ; half the blood fluoresced one-sixty-fourth to one-thirty-second ; half the liver a little more than one-sixteenth ; all the bile a little less than one-fourth ; half the lenses a little less than one-sixty-fourth ; all the humours a little more than one-sixteenth ; half the nerves one-sixtyfourth to one-thirty-second of a grain of quinine to a litre of water . 16 . Another guineapig was killed four hours after five grains of sulphate of quinine , in two doses , with half an hour 's interval . The fluorescence of the different extracts of the tissues was compared with that of pig 4 , that had taken no quinine , and with pigs 21 and 24 , that were killed after taking a dose of five grains eight and thirty-two hours previously . The liver , the kidney , the brain , and the muscle gave a fluorescence about equal to one grain of quinine in a litre of water ; the blood rather less ; the nerves rather more than the blood ; the lenses and the humours less than the blood . 17 . Another pig was killed four hours and a half after four grains of quinine . The whole of each organ was taken ; the muscle gave a fluorescence equalling from one-half to one grain of quinine to a litre of water ; the brain one-sixteenth to one-eighth of a grain ; the kidney fluoresced nearly equal to one grain ; the urine rather more than one grain ; the blood oneeighth to one-fourth ; the liver nearly one ; the bile a little more than oneeighth ; the lenses , humours , and nerves fluoresced less than one-sixtyfourth of a grain of quinine to a litre of water . This pig was compared with one which was given no quinine . 18 . Another pig was killed five hours and a half after six grains of sulphate of quinine , given in three doses , with twenty minutes ' interval . It was very much affected . The extract of its tissues was compared with pig 3 , which had taken no quinine ; the liver , kidney , and muscle fluoresced very strongly ; the brain fluoresced strongly ; the blood fluoresced between one-fifth and two-fifths of a grain to a litre of water ; the nerves and the lenses fluoresced much less . 19 . Another pig was killed six hours after four grains of sulphate of quinine . The liver and kidney fluoresced equal to from one-half to onefourth of a grain of sulphate of quinine to alitre of water ; the urine from one-eighth to one-quarter ; the blood fluoresced about one-eighth , the muscle a little more ; the brain and the humours of the eye about one-sixteenth of a grain of quinine ; the lenses between one-sixteenth and onethirty-second , and the nerves rather less than one-thirty-second part of a grain of quinine ; the fluorescence was compared with pig 6 , that had taken no quinine . 20 . Another pig was killed six hours after four grains of sulphate of quinine . The liver gave a fluorescence equal to between one and two grains of sulphate of quinine ; the kidney and the urine gave a fluorescence equal to one grain of quinine ; the blood fluoresced between one grain and half a grain ; the bile equalled three-quarters of a grain ; the muscles and the brain one-quarter of a grain ; the nerves one-sixteenth of a grain ; the [ Apr. 12 , 84 humours rather more than one-thirty-second of a grain ; and the lenses between one-thirty-second and one-sixty-fourth of a grain to a litre of water . 21 . Another guineapig was killed in eight hours after taking five grains of sulphate of quinine , in two doses , with half an hour 's interval . The extract of its tissues was compared with pig 8 , which had taken no quinine , and with pig 16 and pig 24 , which were killed four hours and thirty-two hours after taking five grains of quinine ; the fluorescence of the liver was very strong ; the muscles , the brain , and the kidneys showed the fluorescence very distinctly ; the fluorescence of the urine equalled from two-fifths to three-fifths of a grain of quinine ; the bile was not more than one-twentieth of a grain of quinine ; the blood fluoresced more distinctly ; the lenses and the humours not so much , and the nerves least of all . This pig was with young when killed , and the fluorescence of the foetus was distinct ; the fluorescence of the liquor amnii was less than that of the foetus . 22 . Another pig was killed in twenty-four hours after taking four grains of sulphate of quinine . The fluorescence of its textures was compared with pig 6 , that had taken no quinine ; the fluorescence of the liver and kidney was equal to half a grain of quinine ; the blood and bile fluoresced equal to one-eighth of a grain ; the urine between one-eighth and one-sixteenth ; the muscle the same ; the brain and the humours rather less than one-sixteenth of a grain ; the lenses and the nerves about one-thirty-second of a grain of quinine to a litre of water . 23 . Another pig was killed twenty-four hours after taking six grains of quinine , in three doses , with 20 minutes ' interval . The fluorescence was compared with pig 3 , which had taken no quinine ; the liver showed the mostffluorescence ; the muscles , the kidney , and the brain were next ; the nerves and blood equalled about one-tenth of a grain of quinine , and the lenses fluoresced least of all . 24 . Another pig was killed thirty-two hours after taking five grains of sulphate of quinine . The fluorescence was compared with pig 4 , which had taken no quinine ; the liver fluoresced scarcely more than that of the pig that had taken no quinine , about one-twenty-fifth of a grain to a litre of water ; the kidney fluoresced a little more than that of the pig without quinine ; the fluorescence of the urine was scarcely perceptible , less than one-fiftieth of a grain of quinine ; the muscles a little less than the pig without quinine ; the blood , the nerves , the brain fluoresced very slightly ; the lens and the humours more than any other part . 25 . Another pig was killed forty-eight hours after four grains of sulphate of quinine . The fluorescence was compared with pig 6 , which had taken no quinine ; the extract of the liver and of the blood had a fluorescence equal to one-sixteenth of a grain of quinine in a litre of water ; the bile , the kidney , the urine , the brain , the lenses , the humours , the nerves , and the muscles had each a fluorescence less than one-thirty-second part of a grain of quinine . 1866 . ] 85 Another pig was killed seventy-two hours after four grains of sulphate of quinine . The fluorescence was compared also with pig 6 , which had taken no quinine ; the extract of the liver and of the brain had a fluorescence equal to one-sixteenth of a grain of sulphate of quinine ; the lenses had a fluorescence equal to one-thirty-second part of a grain ; the bile , kidney , urine , the nerves , blood , and muscle had a fluorescence less than onethirty-second part of a grain ; and the humours fluoresced much less than one-thirty-second part of a grain of sulphate of quinine in a litre of water . Fluorescence without quinine , measured by the number of grains of quinine in 100 litres of water ( 176 pints ) . Pig I. Pig 4 . Pig 5 . Pig 6 . Pig 7 . Pig 8 . Liver ... ... ... ... ... . 6 to3 less 6'2 less 1'6 Lenses ... ... ... ... less 3 , , 16 , , 16 Kidney ... ... ... ... . , 3 , , 1-6 , , 16 Urine ... ... ... . , , 3 , , 16 , ,16 Bile ... ... ... . , , 3 , , 16 , , 6 Blood. . 4 to 2 ... 3 , , 16 , , 16 Brain. . less 34 to 2 3 , , 3 , , 6 , , 16 Nerves. . 54 to 2 5 , 3 , , 16 16 Muscles ... . 4 to 2 ... . 3 , , 16 , , 16 Humours ... . 4 to 2 ... . least more l'6 , , 16 Fluorescence after quinine . Pig . 11 . Pig 12 . 'Pig 13 . Pig 14 . Pig 15 . Pigl . l Pig 17 . 15 min. 30 mmin . 1 hour . 3 hours . 3 hours . 4 hrs.t 4hours . Liver. . 75 40 20 to 40 100 to 200 6-2 100 100 -Lenses . 6 to 3 5. . 3 1-6. . 16 Kidney . 75 40 20 100 to 200 12to25 100 100 Urine. . 50 20 to 10 20 100 to 200 12. . 100 Bile ... . 12 20 5 100 to 200 25. . 12-5 Blood. . 50 20 20 100 to 200 1-6 12 to 25 Brain. . 12 10to3 5to3 100to 200 3 100 6 to 12 Nerves . 65 least 6 1-6 to 3. . 1-6 Muscles 50 to 25 20 5 100 to 200 6'2 100 50 to 100 Humours. . 5. . 6 to 3 6'2. . 1-6 Pig 18 . Pig 19 . Pig 21 . Pig 22 , Pig 23 . Pig 24 . pig 25 . Pig 26 . 5-4 hours . 6 hours . 6 hours . 8 hours . 24 hrs . 32 hrs . 48 hrs . 72 hrs . Liver ... . 50 to 25 100 to 200. . 50 466 Lenses ... 6to3 3 to. . 3. . 33 Kidney ... 50 to 25 100. . 50. . 33 Urine ... . 25 to 12 100 4 to 6 12 to 6233 Bile ... ... . . 75 5 12. . 33 Blood. . 20 to40 12 100 to50. . 12. . 63 Brain 6 25 6 ... . 3 rsv ; 33 ... 3 6. . 3. . 33 Muscles. . 12 25. . 12 to. . 33 Hum ours. . 6 3. . 6. . 3 least [ Apr. 12 , 86 From these experiments it is seen that the fluorescent substance which exists naturally in the tissues , at the very highest reaches to 6 grains in 100 litres of water , and usually is between 4 and 1 grains of quinine dissolved in this quantity of water . When quinine has been taken , even in a quarter of an hour the fluorescence may become equal to 75 grains of quinine in 100 litres of water . It is found to be in greatest quantity in the liver and the kidney , and somewhat less in the blood , urine , and muscles ; still less in the brain , nerves , and bile ; and the increase is slightly perceptible even in the lenses . In three hours the maximum effect of the quinine may be reached , the fluorescence being then from 100 to 200 grains of quinine in 100 litres of water . This amount was found in the liver , kidney , urine , bile , blood , brain , and muscles . The increase was much less perceptible in the nerves and in the aqueous humour , and was least in the lenses . In six hours the amount of fluorescence was rather less than in three hours ; in twenty-four hours it was considerably less than half as much as in three hours ; in forty-eight hours there was but little more fluorescent substance than naturally exists in the textures , except in the liver and the blood ; and in seventy-two hours there was no increase except in the liver . Hence , in guineapigs , in fifteen minutes the quinine has passed to all the vascular and probably to the extravascular textures . In three hours the amount of quinine in the textures may be at the maximum , and for six hours it remains in excess ; in twenty-four hours the quinine is much diminished , and in forty-eight hours it is scarcely perceptible anywhere . In order , if possible , to obtain very decisive proof that quinine passed into the non-vascular texture of the lens , we gave two pigs three grains of sulphate of quinine , and half an hour afterwards three grains more ; the animals were killed five hours after the first dose . One lens of each pig was put into glycerine , to be compared with the lenses of two other pigs bought at the same time and place , to which no quinine was given . In the electric light there was no apparent difference , either in the colour or in the brightness of the fluorescence , between the pigs that had taken quinine and those that had taken none . Examined by the spark of the coil , the fluorescence of all four lenses was less than one-sixty-fourth of a grain of quinine in a litre of water ; and scarcely any difference was perceptible , though the fluorescence of the lenses of the pigs that had taken quinine was slightly the strongest . In all , the fluorescence was rendered less strong by the addition of a strong solution of common salt to the solution . Two pigs were both given fifteen grains of sulphate of quinine in five doses of three grains each , with the interval of one hour between each dose . They were killed one hour after the last dose , being , however , almost dead from the effects of the quinine . One lens of each animal was examined in the usual way . The fluorescence in both was equal to one-thirty-second of a grain of quinine in a litre of water , or three grains per 100 litres .

112593

3701662

On the Bursa Fabricii

94

102

Proceedings of the Royal Society of London

John Davy

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0023

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112593

10.1098/rspl.1866.0023

http://www.jstor.org/stable/112593

Biology 2

Biology 1

Biology

II . " On the Bursa Fabricii . " By JOHN DAVY , M.D. , F.R.S. , &c. Received March 24 , 1866 . In this paper I have the honour to submit to the Society some observations which I have made on the Bursa Fabricii-an organ respecting the function of which so little has yet been determined with any certainty , some physiologists regarding it , after the manner of the author who first described it , as a receptaculum seminis , others as the analogue of Cowper 's glands , others as that of the prostate ; and one as that of the urinary bladder of fishes . For the sake of ' order and to save some repetition , before entering into particulars it may not be amiss to state briefly that this peculiar organ , in every instance it is met with , is found to lie low in the cavity of the pelvis , behind the intestine , either directly in the median line , or a little on one side of it ; that it is covered anteriorly by the reflected peritoneum ; is composed mainly of two coats , one an outer muscular , the other an inner mucous , the latter in the instances of most development abounding in follicles ; that it communicates with the cloaca by an opening , in the female , close to the entrance of the oviduct , in the male between and a little inferior to that of each vas deferens , in both inferior to the termination of the ureters* ; and that it has over its orifice , when most perfect , a slight valvular fold , affording some , but not perfect , security against the entrance into its cavity of fsecal matter whilst passing in the act of expulsion . What is remarkable in this organ , giving rise to much of the obscurity adverted to , is the different aspects which it exhibits in the same animal according to age , and the differences as to form and proportional size and degree of persistence which it presents in different species . The number of birds in which I have sought for the organ , and have examined it when found , has been considerable , at least thirty different species , all of them , with the exception of the skylark , belonging to or frequenters of the Lake district . I may further briefly premise that , when the microscope has been used , the power employed has been that of -th inch focal distance , and that , when spermatozoa have been sought for , a drop of a solution of common salt of the sp. gr. 1038 , has been added to the fluid to be examined . In the descriptive part which follows , I propose to confine myself to the more striking examples illustrative of the peculiarities adverted to and likely to aid in accounting for them , passing over the several species , or very briefly noticing them , when displaying n marked difference . I. Common F owl ( Gallus domesticus).-I begin with this bird , as I have had the best opportunity of examining it at different ages . 1 . Of a chicken four days old , the bursa was about the size of a small pea ; it communicated with the cloaca , and was empty . 2 . Of another chicken , seventeen days old , found dead on the 10th of March from cold , the bursa measured *3 by '2 inch ; it was distinctly plicated internally ; it was empty . 3 . Of a young cock , eleven weeks old , examined on the 16th of June , the bursa , of a globular form , was 1 1I inch in diameter ; it communicated with the cloaca by a narrow neck about 15 inch in width ; internally it was strongly plicated ; the projecting laminie were of a crescentic form , about twenty in number , and their width , where widest , was about *4 inch . It contained some turbid fluid , in which were numerous mucus-like corpuscles and a few well-defined spermatozoa . The testes were large ; besides sperm-cells , they contained some spermatozoa . 4 . Of another cock , hatched in July , examined when nineteen weeks and six days old , the bursa , 1'2 inch in diameter , weighed 74 grs. ; it was similar to the preceding in structure , and was empty . 5 . Of a third male , hatched on the 19th of September , examined when twenty-one weeks and one day old , weighing six pounds , the bursa was 1'5 inch in diameter ; its plicae like the preceding , its opening into the cloaca large ; many spermatozoa were found in the little turbid fluid with which they were moistened . The testes were large ; the left weighed 144 grs. , the right 130 grs. ; the vasa deferentia were small . 6 . Of a fourth , hatched on the 18th of October , examinied on the 20th of March , when seventeen weeks and seven days old , weight five pounds , the bursa , compared with the preceding , was of diminished size ; its diameter only '6 inch , its plicae few , short and thick , and bloodshot ; its opening into the cloaca large and exposed , without any valvular protection . It contained a little thick mucus , in which there was commingled an appearance of spermatozoa . The testes were large , and abounded in spermcells and spermatozoa ; and the vasa deferentia were well developed , and contained a cream-like fluid rich in delicate spermatozoa* . 7 . In a fifth , a cock of about six years old , weighing four pounds and a half , no traces of a bursa could be found . The vasa deferentia were large , and were distended with a cream-like fluid abounding in spermatozoa . They terminated well apart in the cloaca , and had neither of them a visible papilla* . The right testis weighed 93'7 grs. , the left 119'7 grs. 8 . Of a young hen , hatched on the 17th of May , examined when eleven weeks old , the bursa was more flask-like than globular ; it measured 1'7 by 1'5 inch . Its plicm were large , and their glandular structure so well developed that the orifices of the follicles , as puncta , were seen with the naked eye . The bursa was empty , merely moistened with mucous fluid . 9 . Of a hen hatched on the 17th of Aarch , examined when seventeen weeks and five days old , the bursa was about the same size and form as that of the preceding ; it contained a small quantity of turbid mucous fluid , in which were seen delicate filaments bearing a resemblance to spermatozoa . 10 . Of another , hatched in May , and which , like the preceding , had never laid , examined when nineteen weeks old , the bursa , which was empty , measured 1'7 by 1'5 inch . 11 . Of a fourth , hatched on the 19th of September , said to have laid and known to have been trod , examined when twenty-four weeks old , the bursa was of shrunken appearance ; it was '5 inch in diameter ; its parietes thick ( '2 inch thick ) ; there were no plica ; it communicated freely with the cloaca , and contained a little mucous fluid in which were seen filaments like spermatozoa , but not unmistakeably such . There was a large ovum nearly ready to be detached from the ovary . A very few tolerably distinct spermatozoa were found in the oviduct , which was well developed . 12 . In a fifth , hatched on the 19th of July , examined when twenty weeks and five days old , after having laid about twenty-five eggs , no vestige of a bursa could be detected t. 13 . Of another , about eight months old , examined on the 17th of March , after having laid three or four eggs , the bursa was of a tubular form , *9 inch long by '1 wide ; its walls were exceedingly thin , and it did not communicate with the cloaca . In the little turbid mucous fluid it contained , a single spermatozoon was detected . There was a fully formed egg in the oviduct , the incrustation of which had begun . Nearest the infundibulum many spermatozoa were found . 14 . In a laying hen about three years old the bursa was reduced to a small hard mass , hardly equal to a pea in size . It contained a minute cavity without an opening into the cloaca . 15 . In another , about three years and a half old , no traces of a bursa could be detected . Its cloaca and oviduct were very large , as were also those of the preceding . II . Pheasant ( Phasianus colchicus ) . In ten examined ( seven males , three females ) , with the exception of three ( inferred to be old birds ) , the organ in question was found . It resembled in structure that of the common fowl of from four to eight months old . In each instance it was empty , merely wet with mucous fluid . These birds were shot in November , December , January , and February . Not knowing their precise age , but supposing them to have been hatched in the spring , their bursa as to size was somewhat less than that of the common fowl . The smallest , that of a hen shot in February , measured '3 inch by 2 ; it retained its plicated structure , and freely communicated with the cloaca . III . Partridge ( Perdix cinerea).-Of this bird three specimens have been examined . In one , apparently old , no trace could be found of a bursa . In the other two , in which it occurred , it resembled in form and structure that of the common fowl ; it measured *4 inch by '3 . These were young birds which had taken wing . IV . Turkey ( Meleagris gallopavo ) . In three instances of this bird , all hatched in spring , one examined in October , one in December , one in January , the bursa was found similar to that of the common fowl , and in each nearly of the same size , about . 5 inch by 7 . V. Grouse ( Tetrao scoticus ) . In a young bird , not fully fledged , just capable of a short flight , shot in the island of Lewis on the 12th of August , expressly for the purpose of examination , the bursa was found small , about the size of a pea . Air was found in its humeri , but only partially in its femora . In two , both from Scotland , later in the season , no bursa could be detected . Their femora contained air as well as their humeri . VI . Pigeon ( Columba domestica ) . In two full-grown males examined in September , no trace was found of a bursa ; in other two ( these younger birds ) the bursa was pretty large . VII . Buzztard ( Falco buteo).-Of a young one taken from its nest on the 9th of June , when about a fortnight old , the bursa was globular and comparatively large , about *8 inch in diameter , non-plicated , and empty . This nestling weighed 5193 grs. ; it was covered , except at the umbilicus , where bare , with plush-like yellow feathers , thick , very closely set , equal in weight to 647 grs. VIII . Sparrow-hawk ( Falco nisus).-Of a young bird , examined on the 31st of July , just capable of flight , weighing 3686 grs. , its sternum still cartilaginous , its humeri only partially filled with air , the bursa was small . In another , a male , apparently an old bird , shot on the 8th of March , no traces of bursa were found . It weighed 2836 grs. IX . Tawny Owl ( Strix stridula).-Of a young one taken from its nest on the 21st of June , when well fledged , but its quill-feathers not fully formed , weight 4496 grs. , the bursa was globular and comparatively large , *7 inch 1866.1 in diameter . It contained a good deal of turbid urinary fluid abounding in lithate of ammonia . It had no air in any of its bones . In an old bird , the parent of the preceding , no bursa was found . X. Cuckoo ( Cuculus canorus).-Of a young one shot on the 25th of August , weight 1310 grs. ( judging from its plumage , a bird of this season ) , the bursa was very small . In another , a male* , an older bird , shot on the 6th of June , weight 1768 grs. , no traces could be found of a bursa . XI . Common Goose.-Of one hatched in the spring , examined when about six months old , the bursa , of an ovoid form , measured 1'2 by '7 inch . It was plicated , like that of the common fowl . Of two others , one four months old , one of about eight months , the bursa was about the same size as the preceding . XII . Common Duck.--Of one , a male hatched in March , the bursa was of a cylindrical form , 1'6 inch long by *4 inch wide . Its lining membrane was without plicae ; the apertures of the mucous follicles were conspicuous , and arranged in parallel lines . It contained some dark fmecal matter similar to that in the intestine . Of another male , about three months old , the bursa was of a flask-like form , 2-6 inches in length , '6 inch in width where widest ; in structure like the preceding . It contained a turbid greyish fluid , in which were suspended granules and small globules . It was coagulated by nitric acid . Of a female , about a month older , of the same brood , the bursa resembled the last . Of another female , a little more than a year old , the bursa was very small ; its cavity was not quite obliterated , nor was its opening into the cloaca closed . Of a male about two years old , no traces remained of a bursa . XIII . Water-hen ( Gallinula chloropus).-Of a male shot in November , the bursa , of a flask-like form , was *6 inch by A4 ; its cavity was small and without plicae . XIV . Common Coot ( Ftlica atra ) . In a male shot on the 8th of Miarch no bursa was found . XV . Common Gull ( Larus canus).-The same remark applies to one examined in January . XVI . foodcock ( Scolopax rusticola ) . In two examined , one in December , the other in February , no traces of a bursa were found . XVII . Rook ( Corvus frugilegus).-Of this bird thirteen specimens have been examined . In eight no traces of a bursa were detected ; from their appearance and the quality of their bones , it was inferred that they were a year or more old . In the remaining five a bursa was met with ; three were examined in May , two in August ; all had the marks of young birds . Of one , which weighed 6132 grs. , caught when not quite capable of flight , the bursa was nearly globular and about '7 by *6 inch ; it was distended , as was also the cloaca , with a turbid fluid abounding in lithate of ammonia . Its inner surface was not plicated , but slightly pitted . Of the others , the bursa differed little from the last ; it was somewhat smaller . In the bursa of one of these some flakes were found , consisting chiefly of lithate of ammonia . XVIII . Carrion-crow ( C. corone).-Of a young male shot on the 21st of June the bursa was globular , very like that of the rook , about *7 inch in diameter ; it contained some flakes of lithate of ammonia . Of another , shot on the 30th of June , weight 6163 grs. , the bursa was somewhat different in form ; it was broadest at its base ; it measured '9 by *8 inch . Of one killed on the 16th of July , weight 5653 grs. , the bursa was smaller ; it contained some flakes of lithate of ammonia . Of a fourth , killed in February , which , judging from the smallness of the oviduct , was not an old bird , the bursa , had it not been for its opening into the cloaca , might have escaped observation , not on account of its smallness , for it was little less than that of the preceding , but from the extreme thinness of its coats and adherence to the adjoining tissues . XIX . Jackdaw ( C. monedula).-Three specimens have been examined . Two of these were old ; in neither of them was there a bursa : one was young ; it was shot on the 1 1th of July , and was fully fledged ; its bursa was pretty large , similar to that of the rook , and empty . XX . Jay ( C. glandarius).-Of one , judging from the state of its bones , hatched in spring , the bursa was comparatively large , heart-shaped , measuring ? 6 by *4 inch . Its cavity was small ; its inner surface smooth , without plicae . XXI . Blackbird ( Turdus merula).-Six different specimens have been examined . In an old bird shot in M arch , a male , no trace of a bursa was found . In an unfledged nestling , weighing 112 grs. , found dead , the bursa was so thin as to be translucent ; it was proportionally large , and contained some flakes of lithate of ammonia . In the others , which were examined between the middle of June and the beginning of October , none of them , it was inferred , more than five months old , the bursa , nearly globular , was from about '4 to *5 inch in diameter ; its lining membrane was smooth ; its parietes proportionally thick . In each instance it was empty . XXII . Song-thrush ( T. musicus ) . In an old male examined on the 28th of June no bursa was found . Of two young ones obtained on the 15th of the same month , the bursa was about the size of a large pea ; one was empty , the other contained some lithate of ammonia . XXIII . Water-ousel ( T. cinclus ) . In one , a male , probably a young one , a small bursa was found . It was shot on the 11th of November . In another , an older bird ( judging from its appearance ) , shot at the same time , there was no trace of a bursa* ; and the same remark applies to a third examined in January . XXIV . Common Starling ( Sturnus vulgaris).-Of a young one shot on the 29th of June , the bursa was about the size of that of theyoung thrush . In two old birds shot on the 7th of March , not a trace of the organ was found . XXV . Skylark ( Alauda arvensis ) . In two examined . in January there was the like deficiency . XXVI . CiZffchaff ( Trochilus minor).-Of one , a young bird , examined on the 14th of July , the bursa , of moderate size , contained a little fsecal matter . In another , an older bird , shot in March no bursa could be found . XXVII . Robin ( Sylvia rubecula).-Of a young one found dead on the 16th of June , still warm , weight 255 grs. , the bursa was of moderate size . Of another , nearly fully fledged , found dead on the 25th of June , weight 285 grs. , the bursa was comparatively large , exceeding a little in size that of the preceding . XXVIII . Yellow Ammer ( Emberiza citrinella ) . In one , a male , its testes abounding in spermatozoa , examined on the 16th of June , there was no trace of a bursa . XXIX . Blue Tit ( Parus ceruleus).-Of two young ones examined on the 8th of June , when just able to fly , one weighing 177'5 grs. , the other 162 grs. , the bursa was comparatively large ; in each it was empty . XXX . Cole Tit ( P. ater ) . In one examined in February no trace of the organ could be found . XXXI . Martin ( Hirundo urbica).-Of three young ones taken from the nest on the 10th of July , the bursa was comparatively large ; in each it was empty . One nestling weighed 414 grs. , another 398 grs. , the third 423'5 grs. The parent birds were both found of less weight ; that of the male was 263 grs. , of the female 287'4 grs. In the latter a distinct bursa was found , little less than that of the young birds . Search was made for spermatozoa , but none were found in it . Of the male , the pelvis was so injured by shot that it was useless for examination . In a male shot on the 1st of August , the testes of which contained spermatozoa , no trace of a bursa was found . From the preceding results may not the following conclusions be drawn ? 1st , That in some birds , as in the common fowl , and probably in all the gallinaceous family , and that of the Anatidme , the bursa increases in size and in completeness of organization up to a certain age , beyond which it gradually diminishes equally in both sexes , and eventually disappears . 2nd . That in other birds , those of rapid growth , which take wing as soon as they are capable of flight , the bursa is comparatively large whilst they are nestlings , does not increase conspicuously , if at all , with their growth , but rather diminishes , and after a certain age disappears , and probably sooner than in the first mentioned . The buzzard and owl are examples , and probably all birds of the same family , all of the Corvince , all of the thrush kind , and all the smaller birds , with the exception perhaps of the female martin . Of the uses of the organ , I venture to conjecture , founding my conjectures on what I have observed , that they may be provisional and various ; that in some birds , whilst nestlings , it may act the part of a urinary bladder , as witnessed in the instance of the young owl , and in some of the young rooks , crows , and thrushes , thereby tending to prevent the fouling of the nests ; that in others it may serve as a seminal reservoir at an early period , and in both male and female in the instances mentioned , in which it has been found most completely formed before the attainment of full sizein the male before the vasa deferentia are fully developed , in the female so long as the oviduct is still small and unexpanded ; and that generally , as the organ is more or less amply supplied with mucous follicles , it may serve , by the secretion it yields , to lubricate the cloaca with which it is connected , and to aid in its functions . These conjectures , or inferences , if deserving of being so considered , might be supported by what we know of the structure of the part and its position in relation to the termination of the ureters , of the spermatic vessels , and of the oviduct ; but I think it better to rest them on the facts observedthe urinary matter detected in the organ in some instances , the spermatozoa in others* , and the mucous fluid generally . But granting even that the bursa may be useful , and in the female as well as in the male , in aid of fecundation , as Fabricius supposed , yet his extreme view that that aid , in the stored-up spermatic fluid in the bursa of the hen bird , might suffice for a year , as stated in the subjoined passaget , for which and for other extracts I am indebted to the kindness of Professor Sharpey , is both highly improbable , and is opposed by the fact of the decrease of the bursa with the advancing age of the fowl , and the enlargement of the ovi* As in no instance I have yet found unquestionable spermatozoa in the bursa of the young hen , I cannot fairly infer that the bursa in the female is a receptaculum seminis ; but as in two instances there were detected in it filaments which were very like these bodies , and in one a single pretty distinct spermatozoon , and further , as the bursa seems to diminish rapidly as the oviduct becomes developed and not till then , is it not probable that for a short time it may perform the part assigned , as conjectured above ? It need hardly be remarked that the mucous secretion of the bursa adds to the difficulty of demonstrating the presence of spermatozoa . t " Semen autem Galli ad podicem immittitur , et in vesica reponitur et conservatur , quousque pullus conformetur ; immo vero per totum integrum anni tempus inibi servatur , postea quam semel admisso Gallo , ova omnia per totum illud anni tempus ftecunda redduntur , tanquam vesica unicum ob id foramen habente , ut in concluso loco semen Galli diutius ut in proprio et congrlo loco servetur."-Opp . Omnia , Lugd. Bat . 1738 , p. 21 . duct and of the vasa deferentia . Harvey , who was opposed to the notion of Fabricius , expresses the opinion that an intercourse once or twice repeated might suffice to impregnate a whole bunch of yelks , he having found that an egg laid on the 20th day of seclusion of a hen produced a chick* . This fact is an interesting one , however explained . It might be adduced in favour of the opinion of Fabricius ; but inasmuch as the passage of the fully-formed egg in the act of expulsion does not necessarily secure the expulsion of any spermatozoa previously received into the oviduct , it is of little value in the argument : and here I may mention that I have detected spermatozoa in the oviduct , even in that portion in which the egg was receiving its calcareous incrustation .

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Researches on Gun-Cotton.--Memoir I. Manufacture and Composition of Gun-Cotton. [Abstract]

102

106

Proceedings of the Royal Society of London

F. A. Abel

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112594

http://www.jstor.org/stable/112594

Chemistry 2

Chemistry 1

Chemistry

III . ' Reesearches on Gun-cotton.---Memoir . Manufacture and Composition of Gun-cottono " By F. A. ABEL , F.R.S. , V.P.C.S. Received April 10 , 1866 . ( Abstract . ) A review of the researches on the production , properties , and composition of gun-cotton hitherto published , and a brief examin-ation into the probable causes of the discrepancies exhibited between the results and conclusions of different experimenters , are followed in this paper by a criticism of the several steps in the system of manufacture of gun-cotton , as prescribed by Baron v. Lenk . The conclusions arrived at on this subject are founded upon carefully conducted laboratory-experiments , and upon extensive manufacturing operations carried on during the last three years at the Royal Gunpowder Works , Waltliam Abbey . In some of these operations v. Lenk 's system of manufacture , as originally communicated to the English Government by that of Austria , was strictly followed ; in others , various modifications were introduced in different stages of the manufacture-such as in the composition of the acids used , in the proportion borne by the cotton to the acids in which it remained immersed , in the duration of the treatment of cotton with the acids , and in the methods of purification to which the gun-cotton was submitted . Exception is taken to one or two points in the general system of manufacture , and directions are indicated in which they may be advantageously modified ; but the general conclusion arrived at is that , although Baron v. Lenk cannot be said to have initiated any new principle as applied to the production of gun-cotton , he has succeeded in so greatly perfecting the process of converting cotton into the most explosive form of pyroxyline or gun-cotton , and also the methods of purification , as to render a simple attention to his clear and definite regulations alone necessary to ensure the O Opera Omnia , a Col. Aled . Lond. ed. 1766 , p. 206 . Mr. Abel on Gun-cotton . manufacture of very uniform products , which are unquestionably much more perfect in their nature than those obtained in the earlier days of the history of gun-cotton . Great stress is laid upon the fact that deviations from the prescribed process , which at first sight may appear trivial ( such as a slight modification in the strength of the acids used , the neglect of proper cooling-arrangements ) , are certain to lead to variations in the products of manufacture , affecting their explosive characters , or their permanence , or both . A considerable deviation from the normal composition , due evidently to some accidental irregularities in the course of manufacture pursued , has been exhibited occasionally by gun-cotton obtained from the manufactories at Hirtenberg and Stowmarket . The composition of gun-cotton has been made the subject of a very extensive series of experiments , both analytical and synthetical . The material employed in the analytical researches consisted of ordinary products of manufacture , prepared at Waltham Abbey , and obtained from Iirtenberg and Stowmarket . The general analytical results are as follows : Air-dry gun-cotton contains very uniformly about two per cent. of water , which proportion it reabsorbs rapidly from the atmosphere after desiccation . If exposed to a moist confined atmosphere , it will gradually absorb as much as six per cent. of water ; but it rarely retains more than two per cent. upon re-exposure to open air . The mineral constituents of gun-cotton vary according to the quality of the water employed in its purification . The average proportion of ash furnished by gun-cotton prepared at Waltham Abbey , where the water used is hard , amounts to one per cent. It should be observed that the process of " silicating " the gun-cotton , which is prescribed by Von Lenk , but the value of which is not admitted , has been applied at Waltham Abbey only in special experimental operations . Its use naturally adds to the mineral constituents contained in the finished products . The proportions of matters soluble in alcohol alone , and in mixtures of alcohol and ether , were found to be remark : bly uniform in products of manufacture obtained by strictly following Voi Lenk 's directions . In the ordinary products from Waltham Abbey , the n atter extractable by alcohol amounted to between 0'75 and 1 per cent. , and consisted of a yellowish nitrogenized substance possessed of acid characters , and evidently produced from matters foreign to cellulose ( which are retained by cotton fibre after its purification ) , and the products of oxidation which escape complete removal when the gun-cotton is submitted to purification in an alkaline bath . The average proportion of matter extractable by ether and alcohol after the alcoholic treatment is from 1 to 1'5 per cent. This consists of one or more of the lower products obtained by the action of nitric acid upon cotton-wool , the existence of which was established by Hadow . The causes of the invariable production of small proportions of these substances in the ordinary manufacturing operations , and of their existence in larger quantities in exceptional instances , have been carefully examined into . Their absolute removal from specimens of gun-cotton , purified for analytical purposes , was found to be almost impossible . The methods employed for determining the proportions of carbon , hydrogen , and nitrogen in gun-cotton , and the relative proportions of carbonic acid and nitrogen furnished by its combustion , have been very carefully tested . Four different methods of determining the carbon were employed , and forty-nine successful estimations of that element have been accomplished in a variety of products of manufacture . A number of very concordant hydrogen-determinations , and eighteen direct estimations of the volumes of nitrogen furnished by the complete oxidation of gun-cotton , have been made . The individual as well as the mean results obtained in these analytical experiments correspond much more closely to the requirements of the formula GC6 I N3 O =-C6 13 NO )1 05 trinitro-cellulose , or CG2 H0147 , 3N2 05 trinitric cellulose ) than to the formula recently assigned for gun-cotton by Pelouze and Maury , U2 H1 01 , 5 N2 0 . The determinations of the comparative volumes of carbonic acid and nitrogen have furnished results closely in accordance with those of the direct determination of nitrogen . Since the specimens of gun-cotton analyzed always retained small quantities of the products soluble in ether and alcohol , it was to be expected that the proportion of nitrogen found would be slightly below , and consequently that the carbon-results would be somewhat above , those which the chemically pure substance should furnish . The variations exhibited by the analytical results do not exceed such as are ascribable to the above cause . A number of experiments were instituted with I-Iadow 's method of determining the composition of gun-cotton , which consists in reducing the latter to cotton by means of potassic sulphydride . The results show that , although the method is useful for controlling the results obtained , by determining the increase of weight which cotton sustains by treatm-ent with nitric acid , it does not afford sufficiently definite and trustworthy data to render it applicable as a method of ascertaining the degree of perfection of manufacturing products , i. e. the extent of freedom of a specimen of the most explosive gun-cotton from admixture with the soluble varieties . The treatment of cotton with nitric and sulphuric acids has been varied in many ways in laboratory experiments , with the view to examine fully into the increase in weight sustained by the former , upon its conversion into the most explosive gun-cotton , and to determine what circumstances may exert an influence upon the amount of increase , -an acid mixture of uniform strength being employed throughout the experiments ( 3 parts by weight of sulphuric acid of spec . grav . 1 84 , and 1 part of nitric acid of spec . grav . 1'52 ) . The results arrived at may be briefly summed up as follows : Finely carded and carefully purified cotton-wool will sustain an increase of weight varying between 81'8 and 82*5 upon 100 parts of cotton , if submitted for 24-48 hours to treatment with a very considerable excess ( about 50 parts to I of cottoll ) of the acid mixture . Similar results may also be obtained by repeatedly treating the same sample of cotton for comparatively brief periods with fresh quantities of acid , provided this treatment be not too greatly prolonged . Lower results ( somewhat above or below 78 upon 100 parts of cotton ) are obtained if the cotton be submitted to treatment with a large excess of acid for only brief or for very protracted periods , or if it be left for about 24 hours in contact with a comparatively limited proportion of acid ( 10 or 15 to 1 of cotton ) . The increase of weight which 100 parts of pure cellulose should sustain by complete conversion into a substance of the formula CG H,7 N3 0,1 is 83'3 ; if converted completely into a substance of the composition 24 H36 0,8 , , 5 N2 0 , it should sustain an increase in weight of 77'78 . There is strong evidence that the differences between the highest results furnished by carefully purified cotton-wool , and the number 83'3 , are to be principally ascribed to the small proportions of foreign matter still existing in the fibre at the time of its conversion . The maximum increase of weight sustained by cotton of ordinary quality , such as is used in gun-cotton-manufacture , is , as might have been anticipated , below the result obtained , under similar conditions , with cotton of finer quality and more thoroughly purified . The highest numbers obtained by treatment of such cotton , in small quantities , with a considerable excess of acid , were somewhat below 181 , from 100 of cotton . The increase of weight which this quality of cotton sustains is , however , more generally about 78 per cent. Experiments are quoted which show that the attainment of lower results with cotton of ordinary quality is ascribable to the existence of higher proportions of foreign matters in the cotton under treatment . Some quantitative manufacturing experiments yielded results considerably below those obtained with some of the same cotton in laboratory operations ( 171 and 176 of gun-cotton having been produced from 100 of cotton ) . The causes of these differences are investigated and explained . The identity in their characters , and close resemblance in composition , of the most perfect results of laboratory experiments , and of the purified products of manufacture , the close approximation frequently exhibited by the weight of the former to the theoretical demands of the formula C6 H7I N3 01 ( which may be expressed as C{3N 02 } 0 , o , r C12 11497 , 3N205 ) , and the satisfactory manner in which the unavoidable production of somewhat lower results in the manufacturing operations admits of practical demonstration , appear to afford conclusive evidence of the correctness of K2 either of the above formulae , as representing the composition of the most explosive gun-cotton , and demonstrate satisfactorily that the material , prepared strictly according to the system of manufacture perfected byVon Lenk , consists uniformly of the substance now generally known as trinitro-cellulose , in a nearly pure condition .

112595

3701662

On the Dentition of Rhinoceros leptorhinus (Owen). [Abstract]

106

107

Proceedings of the Royal Society of London

W. Boyd Dawkins

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6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112595

http://www.jstor.org/stable/112595

Geography

Anatomy 2

Geography

IV . " On the Mysteries of Numbers alluded to by Fermat . " By the Rt. Hon. Sir FREDERICK POLLOCK , Lord Chief Baron , F.R.S. , &c. Received March 19 , 1866 . [ See page 115 . ] April 26 , 1866 . J. P. GASSIOT , Vice-President , in the Chair . The following communications were read : I. c On the Dentition of Rhinoceros leptorhinus ( Owen ) . " By W. BOYD DAWKINS , M.A. , Oxon . , F.G.S. Communicated by Prof. J. PUILLIPS , F.R.S. Received March 28 , 1866 . ( Abstract . ) The fossil remains of the genus Rhinoceros found in Pleistocene deposits in Great Britain indicate four well-defined species . Of these the R. tichorhinus , or the common fossil species , ranged throughout France , Germany , and Northern Russia , and , like its congener the Mammoth , was defended from the intense winter cold by a thick clothing of hair and wool . Its southern limit in the Europeo-Asiatic continent was a line passing through the Pyrenees , the Alps , the northern shore of the Caspian , and the Altai Mountains . It has not yet been proved to have existed in Europe anterior to the deposit of the Boulder Clay . The second species , the R. megarhinus of M. de Christol , characterized by its slender limbs and the absence of the " cloison , " has been determined by the author among remains from the brick-earths occupying the lower part of the Thames valley , and from the Preglacial forest-bed of Cromer . The species ranged from the Norfolk shore southwards through Central France into Italy . In France and Italy it characterizes the Pliocene deposits , being found in the former country in association with Mastodon brevirostris and Halitherium Serresii , in the latter with IM . Arvernensis . From its southern range we may infer that the megarhine species was fitted to inhabit the warm and temperate zones of Europe , just as the tichorhine was peculiarly fitted for the endurance of an Arctic winter . The third species is the R. etruscus of Dr. Falconer , confined to the forest-bed of the Norfolk shore , and , like the R. megarhinus , found in the Pliocenes of France and Italy ; it ranged across the Pyrenees as far as Malaga , and is the only species known to occur in Spain . The fourth , the R. leptorhinus of Professor Owen , is the equivalent of the R. hemitcechus of Dr. Falconer . It is defined as " R. a narines demicloisonnees , " and is probably not the same animal as the R. leptorhinus or " R. d narines non-cloisonnees " of Baron Cuvier , the evidence as to the absence or presence of the cloison in the type of the species being of the most conflicting nature . In Central France it is identical with R. mesotropus and R. velaunus of M. Aymard , the R. Aymardi of M. Pomel , and the R. leptorhinus ( du Puy ) of M. Gervaise . Its dentition is characterized by the presence of the third costa in the upper molar series , coupled with the stoutness of the cingulum , the suppression of the anterior combing plate , the smoothness of the enamel , and the extent to which the upper molars overhang the lower , which causes the enamel on the outer side of the latter to be worn obliquely . The lower molars can be determined by the flattening of the anterior area , coupled with the fine sculpturing of the enamel-surface . In common with the other fossil British Rhinoceroses , it possessed a molar series of six only on either side , and was bicorn . It ranged through England , from the Hyaena-den of Kirkdale in Yorkshire in the north , as far south as the plains of Somersetshire , and as far to the West as Pembrokeshire . It is very generally found in association with Elephas antiquus and Iiippopotamus major , both species which lived in Pliocene times . The association in Wookey Hole Hyaena-den with Elephas primigenius and R. tichorhinus and other characteristic Postglacial mammals proves that it coexisted with the tichorhine species , to which it probably bore the same geographical relation as the Elk does to the Reindeer in the high northern latitudes . The sum of the evidence proves that it was coeval with the Mammoth and tichorhine Rhinoceros , and does not characterize deposits of an earlier epoch in the Pleistocene . It has not as yet been found in Preglacial formations . The R. leptorhinus is more closely allied to the bicorn Rhinoceros of Sumatra than to any other living species .

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Experimental Researches in Magnetism and Electricity. Part I. [Abstract]

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111

Proceedings of the Royal Society of London

H. Wilde

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112596

http://www.jstor.org/stable/112596

Electricity

Measurement

Electricity

II . " Experimental Researches in Magnetism and Electricity."Part I. By H. WILDE , Esq. Communicated by Mr. Faraday . Received March 26 , 1866 . ( Abstract . ) This paper is divided into two sections , the first being on some new and paradoxical phenomena in electro-magnetic induction , and its relation to the principle of the conservation of physical force ; the second on a new and powerful generator of dynamic electricity . The author defines the principle of the conservation of force to be the definite quantitative relation existing between all phenomena whatsoever ; and in the particular application of the principle to the advancement of physical science and the mechanical arts , certain problems are pointed out which , in their solution , bring out results as surprising as they are paradoxical . Although , when rightly interpreted , the results obtained are in strict accordance with the principle of conservation , yet they are , at the same time , contrary to the inferences which are generally drawn from analogical reasonings , and to some of those maxims which philosophers propound for the consideration of others . The author directs attention to some new and paradoxical phenomena arising out of Faraday 's important discovery of magneto-electric induction , the close consideration of which has resulted in the discovery of a means of producing dynamic electricity in quantities unattainable by any apparatus hitherto constructed . He has found that an indefinitely small amount of magnetism , or of dynamic electricity , is capable of inducing an indefinitely large amount of magnetism , and again , that an indefinitely small amount of dynamic electricity , or of magnetism , is capable of evolving an indefinitely large amount of dynamic electricity . The apparatus with which the experiments were made consisted of a compound hollow cylinder of brass and iron , termed by the author a magnet-cylinder , the internal diameter of which was 1inch . On this cylinder could be placed , at pleasure , one or more permanent horseshoe magnets . Each of these permanent magnets weighed about 1 lb. , and would sustain a weight of about 10 lbs. An armature was made to revolve rapidly in the interior of the cylinder , in close proximity to its sides , but without touching . Around this armature 163 feet of insulated copper wire was coiled , 0'03 of an inch in diameter , and the free ends of the wire were connected with a commutator fixed upon the armature-axis , for the purpose of taking the alternating waves of electricity from the machine in one direction only . The direct current of electricity was then transmitted through the coils of a tangent galvanometer ; and as each additional magnet was placed upon the magnet-cylinder , it was found that the quantity of electricity generated in the coils of the armature was very nearly in direct proportion to the number of magnets on the cylinder . Experiments were then made for the purpose of ascertaining what relation existed between the sustaining-power of the permanent magnets on the magnet-cylinder , and that of an electro-magnet excited by the electricity derived from the armature . When four permanent magnets capable of sustaining collectively a weight of 40 lbs. were placed upon the cylinder , and when the submagnet was placed in metallic contact with the poles of the electro-magnet , a weight of 178 lbs.-was required to separate them . With a larger electromagnet a weight of not less than 1080 lbs. was required to overcome the attractive force of the electro-magnet , or twenty-seven times the weight which the four permanent magnets used in exciting it were collectively able to sustain . It was further found that this great difference between the power of a permanent magnet and that of an electro-magnet excited through its agency might be indefinitely increased . Experiments were then made with electro-magnets of various sizes , for the purpose of ascertaining the cause of these paradoxical results . When the wires forming the polar terminals of the magneto-electric machine were connected for a short time with those of a very large electromagnet , a bright spark could be obtained from the electro-helices twentyfive seconds after all connexion with the magneto-electric machine had been broken . Hence it is inferred that an electro-magnet possesses the power of accumulating and retaining a charge of electricity in a manner analogous to , but not identical with , that in which it is retained in insulated submarine cables , and in the Leyden jar . It was also found that the electro-helices offered a temporary resistance to the passage of the current from the magneto-electric machine . When four magnets were placed on the cylinder , the current from the machine did not attain a permanent degree of intensity until an interval of fifteen seconds had elapsed ; but when a more powerful machine was used for exciting the electrohelices , the current attained a permanent degree of intensity after an interval of four seconds had elapsed . The general conclusion which is drawn by the author from a consideration of these experiments is , that when an electro-magnet is excited through the agency of a permanent magnet , the large amount of magnetism manifested in the electro-magnet , simultaneously with the small amount manifested in the permanent magnet , is the constant accompaniment of a correlative amount of electricity evolved from the magneto-electric machine , either all at once , in a large quantity , or by a continuous succession of small quantities , the power which the metals ( but more particularly iron ) possess of accumulating and retaining a temporary charge of electricity , or of magnetism , or of both together ( according to the mode in which these forces are viewed by physicists ) , giving rise to the paradoxical phenomena which form the subject of this part of the investigation . Having established the fact that a large amount of magnetism can be developed in an electro-magnet by means of a permanent magnet of much smaller power , it appeared reasonable to the author to suppose that a large electro-magnet excited by means of a small magneto-electric machine could , by suitable arrangements , be made instrumental in evolving a proportionately large amount of dynamic electricity . Two magnet-cylinders were therefore made , having a bore of 2inches , and a length of 121 inches or five times the diameter of the bore . As frequent mention is made of the different-sized machines employed in these investigations , they are distinguished by the calibre , or bore of the magnet-cylinders . Each cylinder was fitted with an armature , round which was coiled an insulated strand of copper wire 67 feet in length , and 0'15 of an inch in diameter . Upon one of the magnet-cylinders sixteen permanent magnets were fixed , and to the sides of the other magnet-cylinder was bolted an electromagnet formed of two rectangular pieces of boiler-plate enveloped with coils of insulated copper wire . The armatures of the 2--inch magnetoelectric and electro-magnetic machines were driven simultaneously at an equal velocity of 2500 revolutions per minute . When the electricity from the magneto-electric machine was transmitted through a piece of No. 20 iron wire 0'04 of an inch in diameter , a length of 3 inches of this wire was made red-hot . When the direct current from the magneto-electric machine was transmitted through the coils of the electro-magnet of the electromagnetic machine , the electricity from the latter melted 8 inches of the same-sized iron wire as was used in the preceding experiment , and a length of 24 inches was made red-hot . When the electro-magnet of a 5-inch machine was excited by the 2'-inch magneto-electric machine , the electricity from the 5-inch electro-magnetic machine melted 15 inches of No. 15 iron wire 0'075 of an inch in diameter . The author having found that an increase in the dimensions of the machines was accompanied by a proportionate and satisfactory increase of the magnetic and electric forces , a 10-inch electro-magnetic machine was constructed : the weight of its electro-magnet is nearly 3 tons , and the total weight of the machine is about 4tons . The machine is furnished with two armatures-one for the production of " intensity"- , and the other for the production of " quantity"-effects . The intensity armature is coiled with an insulated conductor consisting of a bundle of thirteen No. 11 copper wires , each 0 125 of an inch in diameter . The coil is 376 feet in length , and weighs 232 lbs. The quantity armature is enveloped with the folds of an insulated copperplate conductor 67 feet in length , the weight of which is 344 lbs. These armatures are driven at a uniform velocity of 1500 revolutions per minute , by means of a broad leather belt of the strongest description . When the direct current from the 1-5inch magneto-electric machine , having on its cylinder six permanent magnets , was transmitted through the coils of the electro-magnet of the 5-inch electro-magnetic machine , and when the direct current from the latter was simultaneously , and in like manner , transmitted through the coils of the electro-magnet of the 1 0-inch machine , an amount of magnetic force was developed in the large electromagnet far exceeding anything which has hitherto been produced , accompanied by the evolution of an amount of dynamic electricity from the quantity armature so enormous as to melt pieces of cylindrical iron rod 15 inches in length , and fully one-quarter of an inch in diameter . With the same arrangement , the electricity from the quantity armature also melted 15 inches of No. 11 copper wire 0 125 of an inch in diameter . When the intensity armature was placed in the magnet cylinder , the electricity from it melted 7 feet of No. 16 iron wire 0'065 of an inch in diameter , and made a length of 21 feet of the same wire red-hot . The illuminating power of the electricity from the intensity armature is , as might be expected , of the most splendid description . When an electric lamp , furnished with rods of gas-carbon half an inch square , was placed at the top of a lofty building , the light evolved from it was sufficient to cast the shadows from the flames of the street-lamps a quarter of a mile distant upon the neighbouring walls . When viewed from that distance , the rays proceeding from the reflector have all the rich effulgence of sunshine . A piece of the ordinary sensitized paper , such as is used for photographic printing , when exposed to the action of the light for twenty seconds , at a distance of 2 feet from the reflector , was darkened to the same degree as was a piece of the same sheet of paper when exposed for a period of one minute to the direct rays of the sun , at noon , on a very clear day in the month of March . The extraordinary calorific and illuminating powers of the 10-inch machine are all the more remarkable from the fact that they have their origin in six small permanent magnets , weighing only 1 lb. each , and only capable , at most , of sustaining collectively a weight of 60 lbs. ; while the electricity from the magneto-electric machine employed in exciting the electro-magnet was of itself incapable of heating to redness the shortest length of iron wire of the smallest size manufactured . The production of so large an amount of electricity was only obtained ( as might have been anticipated by the physicist ) by a correspondingly large amount of mechanical force ; for it was found that the large electromagnet could be excited to such a degree that the strong leather belt was scarcely able to drive the machine . When the electro-magnet of the 10-inch machine was excited by means of the 21-inch magneto-electric machine alone , about two-thirds of the maximum amount of power from the 10-inch machine was obtained . From a consideration of the combined action of the magneto-electric and electro-magnetic machines , the author points out a remarkable analogy , subsisting between the operation of the static forces of magnetism and of cohesion in modifying dynamical phenomena , which throws additional light upon the nature of the magnetic force . On reviewing and comparing the whole of the analogous phenomena manifested in the operation of the magnetic and cohesive forces under the varied conditions to which the author invites attention , it appears to him that magnetism is a mode of the force of cohesion , or is , if the term be allowed , polar cohesion acting at sensible distances , the equivalent of magnetic force being obtained at the expense of an equivalent of ordinary cohesive force ( in an axial direction ) so long as the iron continues to be magnetized .

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Extract of a Letter from Charles Chambers, Esq., Acting Superintendent of the Bombay Magnetic Observatory, to the President. Dated March 28, 1866

111

114

Proceedings of the Royal Society of London

Charles Chambers

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0027

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112597

10.1098/rspl.1866.0027

http://www.jstor.org/stable/112597

Meteorology

Biography

Meteorology

III . " Extract of a Letter from CHARLES CHAMBERS , Esq. , Acting Superintendent of the Bombay Magnetic Observatory , to the President . Dated March 28 , 1866 . " Communicated by the President . Received April 26 , 1866 . You will probably have heard from Mr. Stewart that the opportunity of applying usefully the experience which I acquired at Kew has been tem porarily accorded to me by the Bombay Government , by my appointment to the superintendence of this Observatory . The confirmation of my present appointment will probably depend upon the sanction of the scheme of improvements for the Observatory which I have just sent in for the consideration of Government . Meanwhile I have arranged the working power of the establishment so as to take up the reduction of the old observations , and I am sure you will be interested to learn that there is a probability of their turning out trustworthy and valuable . The separation of seven years of declination-disturbances has already been effected , with the results shown in the enclosed Tables and Curves ; but as the whole series of observations ( from 1845 to 1865 ) will include two complete cycles of the decenniaI period , and as the reductions have already been so long delayed , I propose completing the twenty-one years before discussing the connected questions and publishing the whole ; it is , however , a little doubtful whether the opportunity of doing this will be afforded me , as the Indian Government , in sanctioning my appointment , have limited its duration to the end of next month ; and though I am hopeful that , partly in consequence of a representation that I have made to the Government , of the wide scope for usefulness that is open to me here , and of what has been effected and has been engaged upon since my arrival six months ago , they may be induced to extend their approval of the appointment until the improvements suggested in my Report shall have been considered , yet it seems right , as there are some interesting points about the results already arrived at , that I should inform you of them whilst I may , especially as in case of a second reference of the matter to the home Government , you will , I believe , consider them good grounds upon which to recommend the continuance of the reductions of the twenty-one consecutive years of the Bombay observations . Referring to page 283 of your paper in the Philosophical Transactions , 1863 , it will be seen that these results supply the required knowledge of the laws of the disturbances at a station intermediate in longitude between Kew and Nertschinsk . The general characteristics of the westerly disturbancediurnal-variation curve are the same as you describe for Pekin and Nertschinsk . The curve is remarkably regular , and the ordinates between 8 P.M. and 4 A.M. have scarcely appreciable values , being in the latter respect like the westerly curve for Hobarton , and the easterly for Kew and St. Helena . The maximum occurs at 11 A.M. , which corresponds to about 18 " Kew astronomical time , implying , by comparison with the corresponding hours of maximum at the other two eastern stations ( Pekin and Nertschinsk ) , a rather slow propagation of the disturbing action from north to south of the eastern part of the northern hemisphere . The other curve ( of easterly disturbance ) presents a less systematic appearance ; and the ratios are at no part of the day smaller than 0'64 , or greater than 1-83 . The Table of aggregate values of disturbance in the several years points very distinctly to a minimum as occurring early in 1864 , thus adding another to the determinations of this turning-point in three former cycles given by you in the third volume of the ' St. Helena Observations , ' and confirming the conclusions you arrived at as to the propriety of the appellation " decennial " to the period in question . The Table does not extend far enough backwards to fix the time of maximum distinctly , but it suffices to place it with probability in the year 1859 . The principal requests that I have made in my Report are for a--set of Kew magnetographs , and for a suitable room , and for a body of computers to work up the old observations . Ratios of the aggregate values of the declination disturbances Astronomicl ho exceeding 1'4 in amount at the several hours in the seven years from 1859 to 1865 inclusive . Kew Westerly Easterly ( approximate ) . disturbances . disturbances . 12 7 '05 '70 13 8 '17 ' 68 14 9 '16 -64 15 10 -14 '84 16 11 -18 -69 17 12 '36 '71 18 13 '80 -92 19 14 '96 1-17 20 15 1-64 1 00 21 16 2-35 1'08 22 17 2-73 1-61 23 18 2-76 1-83 0 19 2-84 1-68 1 20 2-57 1-56 2 21 1-86 1-29 3 22 1'41 ' 99 4 23 1'06 '91 50 '61 -85 61 '40 -85 72 '45 -80 83 -16 1'00 94 '11 '79 10 5.16.70 11 6 -08 '72 Aggregate values in the seven years ... ... ... ... ... ... ... ... ... 2801-1 4538'7 7339-8 113 Ratios of disturbance in the Aggregate values of all disturbseveral years from 1859 to ances exceeding 1-4 in the in e to te m 1864 inclusive to the mean . several years from 1859 to aggregate disturbance in the aggregate disturba-nce in the 1865 inclusive . 8six years taken as unity . Years . Aggregate Years . values . Years . Ratios . 1859 1A43 1859 1532-1 1860 1-33 1860 1421-6 1861 0-89 1861 9518 1862 1-16 1862 1240-5 1863 0-64 1863 691-1 1864 0-56 1864 595-9 1865 906-8 The ratio of the maximum in 1859 to the minimum in 1864 is as 2-6 to 1 .

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On the Tides of the Arctic Seas.--Part III. On the Semidiurnal Tides of Frederiksdal, near Cape Farewell, in Greenland. [Abstract]

114

114

Proceedings of the Royal Society of London

S. Haughton

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112598

http://www.jstor.org/stable/112598

Meteorology

Geography

Meteorology

IV . " C On the Tides of the Arctic Seas.-Part III . On the Semidiurnal Tides of Frederiksdal , near Cape Farewell , in Greenland . By the Rev. S. HAUGHTON , F.R.S. Received April 12 , 1866 . ( Abstract . ) The observations discussed in this paper by the Rev. Dr. Haughton were made for him ( in 1863-64 ) , at the request of Admiral Irminger of the Royal Danish Navy , by Missionary Asboe , at Frederiksdal , near Cape Farewell in Greenland . They proved amply sufficient for the complete discussion of the semidiurnal tide of that interesting locality ; and the following results were obtained:1 . Eccentricity of lunar orbit ... ... ... ... ... ... . . 0'06786 2 . Mass of earth as compared with mass of moon ... . 64'638 3 . Depth of Atlantic deduced from heights ... ... . 10-03 miles . 4 . Depth of Atlantic deduced from times ... ... ... . 3'30 miles .

112599

3701662

On the Mysteries of Numbers Alluded to by Fermat. [Abstract]

115

127

Proceedings of the Royal Society of London

Frederick Pollock

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112599

http://www.jstor.org/stable/112599

Formulae

Measurement

Mathematics

" On the Mysteries of Numbers alluded to by Fermat . " By the Rt. Hon. Sir FREDERICK POLLOCK , Lord Chief Baron , F.R.S. , &c. * ( Abstract . ) This paper is presented as a continuation of one which appeared in the Philosophical Transactions of the Royal Society for 1861 , vol. cli . p. 409 , and the object of it is to call attention to certain properties of odd numbers when placed in a square , according to an arrangement to be explained below . It appears to me probable that these properties are connected with ( if , indeed , they be not actually some form of ) the mysterious properties of numbers , to which Fermat alludes in the announcement of his theorem ( as furnishing the proof of it ) ; for in point of fact these properties give a method by which every odd number can be divided into four square numbers , and every number ( odd or even ) can be divided into not exceeding three triangular numbers . I am not prepared to say whether or not the method affords a demonstration , and proves that it can always be done ; but it always does it , and the cause of its success may be distinctly shown . The properties I allude to are scarcely less interesting and curious than the theorem itself , and present results for which I can find no namne more appropriate than the geometry of numbers , for relations appear to be established between various numbers in the square , which relations are not founded on any arithmetical connexion between them , but on the positions they respectively occupy in tne square of which they form a part . The arrangement of the numbers is as shown in diagram No. 1 . Any odd number ( which may be the subject of inquiry ) is made the first term of a series , increasing from left to right by the numbers 4 , 8 , 12 , 16 , ... ( 4 n ) This series forms the horizontal line at the top ; each term of the series so formed is made the first term of a series , increasing downwards by the numbers 2 , 6 , 10 , 14 ... . ( 4n-2 ) . A square of indefinite magnitude is thus formed , consisting of two sets of series , one set all horizontal , the other set all vertical . 161 is the first number in diagram No. 1 . The result of the arrangement of the two series in the manner above mentioned is the formation of a third set of series , which may be found in the diagonal lines of the square . If from the first number in the square ( 3 a diagonal linie be drawn towards the opposite corner , it will pass ugh the first terms of one portion of the third set of series ; the second , third , and following , terms are takeni alternately from each side of the diagonal line . These series increase by 2 , 4 , 6 , 8 , &c. ... ( 2n ) , and with the exception of one term they are all in the diagonlal lines ( see diagram No. 1 ) , in which the single red line passes through the first terms , and the double red line shows where the terms of the series ( the second , third , &c. ) belonginog to that ( as a first term ) are to be found ; the red inik numbers indicate their order . 12345678 The Nos. 203 , 205 , 209 , 215 , 223 , 233 , 245 , 259 , &c. , &c. , compose the series ; the terms increase by 2 , 4 , 6 , 8 , 10 , &c. ... 2n . Any number in the diagonal from 161 may be the first terni of a similar series . The diagonal from 163 will give all the other first terms of the third set of series . In order to explain the indices which appear in the diagram No. 1 , and to show in what manrner the series are connected with , and pass into each other , it is necessary to point out the properties of the two series which compose the square , and of the third series , which is a niecessary result . All of them have this property in common , -that if you can discover the roots of the squares which compose any term of the series with reference to the nature of the series , and the order in the series of that term , then you know the roots of every term in the series , both before and after that term . The first series iniereases by 4 , 8 , 12 , &c. The indices of the terms of a series so increasing I have made 1 , 3 , 5 , 7 , &c. , and they are put at the top as being comimoni to all the series that are horizontal . For this reason , if two numbers differ by 1 , as n , nz+ 1 , and the larger be iniereased by 1 , and the smaller be diminiished by 1 , and the process be continued , the result will be . 21 , n+ 1 , n-1 , ? I +-2 , nz-2 , n+3 , n-3 , n ? +4 , &c. &c. n--(p-1 ) n+p . If these be treated as roots , the sums of the squares will be 2 2+ 2 + ? I. 2n'+22z+5 , 2n2+2n+ 13 , 2n2 ? + 2n + 25 , &c. &c. 2n2+2n+ 2P2_2p + 1 . The sums of the squares inierease by 4 , 8 , 12 , &c. If therefore the roots of the square , into which any odd number may be divided , bep , q , n , n+ 1 , and the number be increased by 4 , 8 , 12 , &c. ... ( 4n ) , the mnth term in the series will be composed of squares whose roots will be p , q , n-(n-1 ) , n + m ; two of the roots will be constant , the others will vary , and their differences in the successive terms will be 1 , 3 , 5 , 7 , &c. ( 2n1 ) ; and if you discover the roots of any term in the series , you can find the roots of all the terms . The second series resembles the first in having two roots constant , and two variable ; the differences between the variable roots are , in the first term 0 , in the second term 2 , in the third term 4 , &c. , and the indices of the terms are therefore 0 , 2 , 4 , 6 , 8 , 10 , &c. , which are placed vertically by the side of the square . For if two numbers are equal , as ni , An , and one of them be inclreased by 1 , and the other diminished by 1 , and the process be continued , the result will be nn 2z n-1 , n+1 j If these be treated as 2N2 ? +2 n-2 , n+2 > roots , the sunms of < 2n'+S n-3 , n+3 their squares will be 2n 'd 18 &c. & C. J & C. &c. The sums of the squares increase by 2 , 6 , 10 , 14 ... . ( 4nz-2 ) , and the successive differences of the variable roots are 0 , 2 , 4 , 6 , &c. ; and if the roots of the squares inito which any odd number may be divided be p , q , n , z , and the number be increased by 2 , 6 , 10 , &c. , the roots of the mth term will be p , q , n-(mr-l ) , n ? +(n-l ) , and if the roots of any one term be known , the roots of all the others may be found . The small figures in the upper right-hand corner of each division or small square are the indices of the third set of series . In this set all the roots are variable . The character of the first set of series is , that two roots in every term differ by an odd number ; the character of the second set of series is , that two roots in every term differ by anl even number ; but in the third set of series , the algebraic sum of all the roots of the squares into which the successive terms may be divided is successively 1 , 3 , 5 , 7 , 9 , &c. ( an odd number ) : the sum of the roots of the squares into which an odd number can be divided cannot be an even number . The following Table will explain in what manlner the series is formed from the ropts of the squares into which any odd number may be divided , so as to make the algebraic sum equal to 1 . I have preferred to use figures instead of algebraic symbols , as being more readily understood and more easily dealt with ; but the result is the same whatever figures or symbols may be used . The series begins from the centre . Let-7 , -3 , 2 , 9 , which are the roots of the squares into which the odd number 143 may be divided , be placed in the centre , and let the positive roots be increased downwards and decreased upwards , and the negative roots increased upwards and decreased downwards , the result will be as in the Table below : Order of Algebraic Sums Order of Roots . sums of of squares of terms . roots . of roots . terms . 457 12 -13-9-4 3 -23 275 12 10 -12-8-3 4 -19 233 10 8 -11-7-2 5 -15 199 86 -10-6-1 6 -11 173 64 9-5 077 155 42 8-4 183 145 2 Centre 1 7-3 291 143 13 6-2 3710 5 149 3 5-1 4 11 9 163 574 05 12 13 185 79316 13 17 215 911227 14 21 253 11 13 1-3 8 15 25 299 13 &c. &c. &c. It will be observed that the terms of the series 143 , 145 , 149 , 155 , &c. increase by 2 , 4 , 6 , 8,. . ( 2 n ) . In the column of the sums of the roots 1 , 5 , 9 , 13 , &c. increase by 4 . 1 , -3 , -7 , lII decrease by 4 ; the differences of the roots , if arranged in the order of their numerical value , is always the same throughout the series . Note . In the remainder of this paper every odd number that becomes a term in any of the series is expressed by the roots the sum of whose squares form the number itself ; 2 , 3 , 6 , 8 means that the number occupying that division or small square is 113= ( 22+32+ 62+8 ) ; a figure ( or collection of figures ) representing , merely the arithmetical value is put into it circle , thus : 2 , 3 , 6 , 8 Having explained the construction of the square and the indices which belong to the series of which it is composed , I propose to point out the properties which discover the roots of the squares into which the odd numbers ( which are found in the different parts of the square ) may be divided . If the first odd number in the square be of the form ( 4 p+ 2 ) . n+1 ( or 2 n+ 1 , 6 n+1 , 10 n+l , 14 n+1 , &c. ) , n being of any value whatever , the ( n-p)th term will be ( p+ l ) , -p , n , n j ; these are the roots ( the number itself would be 2 n2 ? ? 2p2 + 2p + 1 ) ; and as the index of the nth term is n+(n-1 ) , or 2n-1 , the inidex of the ( n-p)th will be 2 n-(2 p+ 1 ) , and the algebraic sum of the roots may be made equal to the index ; it is therefore a term in a diagonal series Lthat the ( n-p)th term is 2 n+ 2 2p2+ 2p+ 1 , will appear by finding in the usual way the ( n -p)th term of a series whose first term is ( 4 p+ 2 ) . n+ 1 , and the terms of which increase by 4 , 8 , 12 , 16 , &c. ... 4 n ] ; but as two of the roots are cqual , n , n , it is the first term of a vertical series descending , thus : p+ l , p , n , n p++ p , ( n-1 ) , n+1 p+I , p , ( n-2 ) , n+2 p ? + p , , ( n-3 ) , ( n+3 ) . I call this term ( A)* and indicate it by that letter , and from this term the roots of many others may be derived ( which are indicated by other letters connected with A in an invariable manner ) , whose squares will compose the number that belongs to that term . For example , counting 2p ? ? 1 squiares backwards from A is a term I have distinguished as W ; the roots of the number belonging to it are p +1 , ) , ( n)-4p+2 ) , n These roots may , of course , be either positive or negative ; arranging them thus , -p-+ 1 , -p , 4p+ 2 , n , we have the algebraic sum of their roots equal to 2 n6 p+ 3 , which is the index of the square in which W is found going backwards from A , the index of which is 2 n2p +1 ( as already stated ) ; immediately adjoining W are two squares which I have called M and N respectively . M is the term next before W , and is composed of the roots n-2p ? ? ? ?+2 , it-2 p+2 , 3p+2 , p+ 1N is the term next after W , and consists of the roots n-21p , n-2p , 3p+l , p1 Each of these will traverse the squiare diagonally , the algebraic sums of their roots beirig equal to the index ; the roots of W may also be obtained from A by takin-g its roots dowln vertically , making n , n , successively n1 , n+1 , n-2 , + 2 , &c. , until the square is reached , in which the index is 2 n+ 2p+ 1 , and 2 i+ 2p+1 being the arithmetical sum of all the roots of A ; A here becomes a term in a series which moves diagonally , and on being carried up towards the left will give the roots of W. Whclu the indices of the squares through which this vertical series passes equal 2n+ 1 , by makingjp + 1 , p , one positive and the other negative , the term becomes a term in another series which moves diagonally upwards towards the left . This must occur both when the index equals 2 tI and when it equals 2n +1 ; and as the indices increase downwards uniformly by 2 , it follows that 2 ni-1 and 2 n+ 1 will be the indices of contiguous terms of the vertical series , and therefore two contiguous terms will become terms of series moving diagonally upwards to the left ; and as these two series are contiguous to each other , their terms found in the first series ( that is , the series in the top line ) will also be contiguous . These two terms I have designated as AM and AN . AM comes from the term where the index equals 2 n+ 1 , and AN from the terii where the index equals 2 n1 ; the roots of AAI are 0 , 2p+1 , 2-1)n2 , those of AN are 0 , 2 +l , m-2p , I ' andi being arranged thus , --2 )+ 1 , 0 , m-2p+ 2 , it , -2 p+ 1 , 0 , m-2p2 , m , will move diagonally downwards to the left ; and as each of these have two r'oots that differ in onae case by 2 I , in the other by 21+ 2 , the terms in these series that arc parallel to those terms in the first vertical series which have their externlal indices respectively 2 1 ) and 2p+ 2 , the terms of A:iV and AN will ( I say ) in these places become terms in series movirig vertically ; and on being followed up to the series in the top row will be found to give the roots of TMI and N. The roots of MA and N may be -obtained by another method as follows:-As the algebraic sum of the roots of A equals its index , therefoie A is a term in a diagonal series moving downwards towards the left ; and as two of its roots , p ) , i ) + 1 , differ by 1 , it follows that whenever the value of m has been so altered that 2n+1 equals the inidex by making + 1 , p , one positive and the other negative , the term becomes a term in another series , which series will move at right angles to the series last mentioned . Now taking the series which moves to the left of A , it is clear that this result will obtain in . two places ; first , whern the altered value of i makes '2 -1 equal the index , and secondlv , when the altered value of n makes 2 n+1 equal the index . The first of these going up gives the roots of N , the second gives those of M , and these roots are identical with those obtained from AM and AN . The index of A is 2 i2 p+ 1 , therefore when n in moving downwards becomes n+1 , n+2 , + ? 3 ... ... . . 2nz-3 p-F2.2 n-3_p+l + 1 , p being two of the roots of each term in this series ; by adding , p ? ? 1 to the first-mentioned root and p to the other , these two terms will be found to be terms in two horizontal series , of which the first terms are in the first vertical series , and these terms both of them make the diagonal index , and therefore are terms in a diagonal series which , rising towards the right , give the roots of W. A descends diagonally to the left , and on each side of the line which leads to W changes to cross diagonals which lead to M and N. W leads diagonally to the left to R and S , and where it crosses AT changes and goes up to A. M goes down into R , and then diagonally to where it meets the horizontal series from T ; its roots there correspond with the series from T ; it returns to T and uip to A. In like manner N goes down through S to the line from V , and so to V and up to A. R and S go each of them across to the vertical line from A , and so up to A : every term through which these lines pass has the four roots indicated whose squares would make the term . The number of terms in the whole square , whose four roots may be expressed in term of p and n , is very considerable ; and it may be well now to present some skeleton diagrams of the many ways in which certain members of the square are in7varia.6y connected . I propose to exhibit several ( to avoid confusion , which would arise from putting all in one diagram ) ; these do not by any means include all the connexions that exist ; but whatever may be the value of n or p , a number of the form ( 4p+2).n+1 , whether it be 2n+1 , 6n+l , OnX+1 , &c. , and whatever be the value of et , gives the following resuilts . See diagram No. 2 . At the ( n-p)th term there will be A , which descends vertically till the index is 2n1 , then 2n+ 1 , and from these rise up in diagonals AN and AM , as already mentioned . A then further desceinds till the index is equal to 2n + 2p + 1 , when it rises in a diagonal to W. Diagram No. 3 shows certain connexions between AM and AN and other terms in the square . AMt is always -2p-+1 , 0 , n-2pp+2 , ? n , AN is always -2p + 1 , 0 , n -2p , n. If the series in which AMN is a term be carried down diagonally till 0 becomes 2p +1 ( that is 2p +1 places ) , it becomes a term in a diagonal series that intesects it and rises to the top , then goes down to the horizontal series from It , where it becomes a term in that series and passes to where it is below M and rises vertically up to it . AN does the same with respect to the series from S , and rises up to N. If the term AM descends till n 2p +2= 2p 1 , it rises to the left in another diag , onal series and goes on till it crosses M , where it is foiind that the roots are always the same as those which arise from M , descending by means of its two eqiual roots . The term AN does the same with respect to N. If AMIf descend to the margin at am , and one step further into an , and AN descends to an , they will be found to have the same roots , and they will be _ from AMi _ -2p+l , 1 , n-2p+1 , n from AN -2p+ 1 , -l , n-2p+1 , n The only differenice being that in the one case 1 is positive , in the other it is negative ; but whatever be the value of p or n , in this portion or term of the square 1 is always one of the roots . In crossing the two horizontal series from R and S , it will always be found that at the points of intersection the roots of AMi corresponed with the roots of the series from I , and the roots from AN correspond with those from S. Diagram No. 4 exhibits the way in which B , C , P , and Q are connected together . The roots of A at the ( it-p)th square will always be -(+ 1 ) , -p , n , n , aidp ? + 1 , p must be one of them odd , the other even ; therefore , whether n be odd or even , ain odd number will be formed by -(p+ 1 ) , t , or -p , n. The series from A descending diagonally has the roots it , i decreasing , but the niegative roots iniereasing . The differences will continue the same ; and when the series arrives under that index which corresponds to the odd number -(1-)+ 1 ) n , or --p , n , it becomes a term in a horizontal series which goes to P , two terms of which are always p , p+ 1 . W , in descending diag , onally , has its index on reaching PB 1 . When A has descenided so as to reach the evenl number of the two , ( -(p+1 ) , n , -_ ) , n ) , it rises in a vertical series to Q ; and the three series , WR . , BP , CQ , always intersect in the same point or small square , H. The paper then exhibits in a Diagram ( No. 5 ) all the roots which arise from applyij g the method to the odd No. 161 , and shows that the roots of A would be ... ... . . 3 , 2 , 16 , 16 ofW ... ... ... ... . . 3 , 2 , 6 , 16 of Mt , ... ... ... ... . 8 , 3 , 10 , . 10 of N , , ... ... ... ... . 7 , 2 , 12 , 12 of AM , ,5 , 0 , 10 , 16 of AN , ,.5 , 0 , 12 , 16 It shows the roots of the squares marked B , C , P , Q , R , S , and many others ; and , finally , it showrs that 161 would be composed of the squares of the following roots , either 3 , 12 , 2 , 2 , or 10 , 0 , 5 , 6 ; but to set forth the roots of the numbers which are iu Diagram No. 1 , would require a diagramn larger thaui could conveniently be put into a publication of the size of the Proceedings . The roots 10 , 0 , 5 , 6 , if arranged thus , -10 , 0 , 5 , 6 , have 1 for their sum ; but it was proved in the former paper ( see p. 410 , Trans. Roy . Soc. for 1861 ) that if the algebraic sum of the roots be 1 , then the number is the double +1 of a number composed of 3 triangular numbers , 16 1=80 x 2+1 , and 80 is composedof the 3 triangular numbers 55 , 15 , 10 . If therefore any number be doubled , and 1 be added , aln odd number will be obtained , to which the same process may be applied as is here applied to 161 . I have stated that the cause of the success of " the method " ( though it does not at present amounit to a demolnstration ) may be easily slhown . It arises , first , from " the mnethod " requiring every odd number that is a term in any of the series to be represented by the roots of the square numbers that compose it ; and secondly , and more particularly , from every series being connected with at least six others of a different kind which intersect it , each of which is again connected with at least five others , so that when the whole nietwork has been pursued , and the roots which in successioni form every term have beeni recorded , it will be fouild that many different modes of dividing each term into four squares or less will be discovered , i. e. if the numbers be large . I propose to show the manner in which the series are apparently interwoveli by an example from each kind . 21 23 Let the first term in a horizontal series be 22 3 , 7 , 13 , 14 with 22 as the index in the margin , and 21 and 23 being , the indices of the diagonal series which pass through this square ; for , except at the top line , two diagonal series pass through every square . 13 and 14 are the variable roots , which become 12 , 15 , 1 11 , 16 , 1 10 , 17 , 1 9 , 18 , l &c. t in the successive terms ; when in the second term 14 becomes 15 ( 15+7=22 ) , and the roots are 3 , 7 , 12 , 15 , a term in the series which would come down from the second square ; the roots in that square will therefore be 3 , 12 , 4 , 4 ; when 15 becomes 19 the roots will be 3 , 7 , 8 , 19 , and the roots at the top will be 7 , 8 , 8 , 8 ; so when 15 becomes 25 at the tenth term the roots are 3 , 7 , 2 , 25 ; and as 3 , 25=22 , another series rises up with roots of the first term , 7 , 2 , 14 , 14 . 13 diminishes to 0 , and then increases , giving 2 more when it becomes 15 or 19 ; but the series is also crossed by diagonal series ; and when the 21 19 17 iS 13 , & cj.3 index in the two rows from the first term 23 25 27 29 31 , &c. is37 ( the sum of all the roots ) , or 31 ( the sum of the variable plus the differenlce of the constant roots ) , or 17 ( the sum of the variable roots minus the sum of the constant roots ) , or 23 ( the sum of the constant roots minus the difference of the variable ) , a diagonial series arises . Hlere are no less than 10 other series by which this is crossed and associated and connected , and the number cannot in any case be less than 6 . A series of the second kind gives rise to other series crossing it in the same manner mutatis mnutandis , which result is so obvious that it is not necessary further to dwell upon it . A series of the third kind has all the differences of its roots the 13 same in each term . Let -7 , 2 , 4 , 14 be a term in a diagonal series at the top row of the system . 11 13 15 92 10 0 8 , 13 , 2 , 2 -7 , 2 , 4 , 14 6 , 15 , 4 , 4 Thus : __9 ~~~~~~~~~17 92 10 92 To 2 -8 , 1,3 , 13 -6 , 3 , 5 , 15 When it reaches to the left and to the right , the second place , as 3-1=2 and 5-3 2 , it furnishes two vertical series ; at the tenth row it furnishes two more ; at the twelfth row two more . Wheni it gets into the column whose index is 11 and then 9 , before it reaches the margin or outer edge , it furnishes two horizontal series ; and after it has passed the margin at 9 and 11 it furnishes two more , and at 21 it furniishes another . Here are six new vertical and five new horizontal series ; besides which it fiurnishes at least two other diagonal series which cross it . Having stated the properties which belong to the square , if the first odd number in it be of the form ( 4p + 2).n ? ? 1 , and that whether it be 2n + 1 , 6n ? ? 1 , l On ? ? 1 , &c. , or whatever be the value of ni , certain squares may be found which I distinguish as A , B , C , H , P , Q , W , M , N , AM , AN , R , S , T , V , &c. , which are connected together by a community of roots where the series cross each other in a manner that is invariable . The Diagram No. 3 is another example of the manner in which certain of the terms in the different series communicate with each other , by the roots being comMon to both , at the point where they cross . AM passes diagonally to am , down to an , and up to AN . AN , in like manner , goes down to an and up to am and AM . If the first term of the square be an odd number of the form ( 4p+2 ) n+1 , the roots from AM are in an -(2p + 1 ) , 1 , ( n-2p + 1 ) , n. The roots from AN are ( 2p + ) -1 , ( n-2p+ 1 ) , n. The iindices of the diagonal series are 2n-(4p+ ) and the algebraic sum of the roots is the one or the other , according as 1 is + or- ; but AM also passes to the series from1 R , and AN to the series from S , and go to R and S , and thus go up to W. AM also reaches the vertical line from M , and passes up to M , as AN does to N. Lastly , AM goes to N thus , and AN to W in a similar manner . Whatever be the Proc. Ror . Soc. Vo0i XVPl . Ill. D)iagram IN ? Il I___ _3579I 13 15 17 19 10on + 131 n]=is 01 165 173 185 201 221 2 273 305 341 35317 187 923 27 15 ; 41 1697'3 193 2 229 253 281 349 64 179 183 199 2 219 239 263 291 323 9715 17 29 X2|1 191 273 913 25 , 871 93 1 197 [ } < 1 217 2 253 277 305 337 9 373 691 55 17 I9 21 23 22 29 27 2 12 1 237 245 257 273 293 3+5 377 413 |41 | 23 1271 1283 2 99 3139 3 43 13 I 403 1439 161 94 25 301 313 29 349 1 373 401 3 469 1 19 21 253 25 2 29 31 33 35 37 18 21 231 227 2 > 347 3563 381 407 435 467 503 2 21 23 25 7 27 9 31 33 35 37 39 201 361 365 2 373 5 401 421 445 473 505 541 values of p and n , these connexions occur , but the form of them varies with the values of p and n. I have pointed out some of the results of having as the first term in the square an odd number of the form ( 4p + 2 ) , n+ 1 ; the forms will be 2n + 1 , Gn+1 , lOn+1 , 14n+1 , &c. , in which p may be 0 , 1 , 2 , 3 , &c. But there is another form which gives similar results , viz. 4pn + ( 2p + 1 ) , which is in many respects the " converse " of the other ; the forms will be 4n + 3 , 8n+5 , 12n+7 , 16n+9 , &c. These are the first terms to which this system gives rise . The ( n-p-1 ) th term is always Pp , p , n , n+ 1 . In the former system n produced the equal roots and p the uniequal ; here , p produces the equal and n the unequal roots , and 1 call the ( n-pI)th term A a & .n the other . This system has also W and M and N on each side of it , and other squares similar to the other , but the roots of which they are composed are differenitly formed . M and N come from below . W , instead of being -p+ 1 , -p , ,n-4p+2 , n , will be -3p , p , ( 'n-2p ) , ( i ? ? 1 -2p ) ) , and other terms are similarly altered , but the general result is the same . A specimen of a square of this form is given in Diagram No. 8 , but which canniot be reduced to the size of the Proceedings , where p=3 andn=16 ; the first number is 199 , and the square is completed so far as to show 5 , 13 , 1 , 2 that the roots of the 4 squiares whose sum is 19)9 , -3 , l , 10 1 , 10 ) , 7 , 7 but neither in this Diagram nor in Diagram No. 5 is the whole square completed ( to avoid confusion ) ; but if the series be traced in succession , the entire Diagram 6 would be filled up , and every term would disclose the roots whose squares compose it . In this mannier every odd number in all the series is divided into the squares that compose it ( not exceeding 4 ) , the squares being indicated by their roots . The two systems of ( 4p ? ? 2 ) xn +1 and 4 1.n ? +2p +1 include every possible odd numlber ; 4n +3 includes every alternate odd number from 3 ; 8n+5 every fourth number from 5 , and so on ; 2n ? +1 includes every odd number ; Gn ? ? 1 every third odd number . Many odd numbers belong to both systems , and to more than one in each . 15 1 is an examnple ; it is either 10(n +1 ( n-=15 ) , or it is 12n+ 7 ( n= 12 ) . The paper contains a Diagram ( No. 9 ) exhibiting the odd number 151 ) I as belonging to both systems ; but the Diagramn cannot be redu-ced . The roots of the squares that compose 151 are ( 10 . 1.5. . 5 ) , or ( 3 . 9 . 5 . 6 ) . i+.z E n ? Cs 0 F ; ~= 4wIo 0t12~~~~t cec~~~~~~~~~c 01_ 2 dF DX2X0 bnCD ? . ) H~~~ '1t ' Q 01 C. ) a cC.~~~~~~~~C n^tn Qq Fil t~~~~E cEI 4S : , a 01 _____ 0CI)S.~~~ ~~ 1 ? .~ -~ 4 ) I I~~~~~~~~~~~~)ht 0 r01~~~~~~~4 + 01 . 011 I U2~~~~~ '~~~gt Diagram No. 7 . There is an interval of n-3p +3 squares from the 1st term . *2n6P+4 *2n-6p Jr 4 p-+2 , pn 21)+ 2 , nX2p+ I __ 2 6+ 1 This Diagram ( No. 7 ) 2n-6l ) +4 -39+ 12 shows in terms of n and p the SX+ 1 , P-2p roots of X , S , an ( which ___ 2_____ _2p _ comes down diagonally from AN ) , T , and V , and the There is here an interval of number of squares between ( p-I ) squares from S to an . them ; the relative positions --______________ _ of these terms depend entirely 2n-4p +3 on p , and are always the + same for the same value of 2n 4.2 +2 _ , -p 2p P1 } an -_+_ , I Terms similar to these in n2p + 1 , n crease indefinitely as n increases . The value of cerThere is here an interval of taimi roots is independent of ( p-1 ) squiares from an to T. i , and therefore is the same -____________________ __ w Ufor every value of n. 2n-2p32 T p11 + I , p+l n-1 , 2n 2n-2p 2n-2p-1 v P,.r %pn , n+ 1

112600

3701662

Report on the Levelling from the Mediterranean to the Dead Sea

128

131

Proceedings of the Royal Society of London

Henry James

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0030

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112600

10.1098/rspl.1866.0030

http://www.jstor.org/stable/112600

Geography

Reporting

Geography

I. " Report on the Levelling from the Mediterranean to the Dead Sea . " By Colonel Sir HENRY JAMES , R.E. , F.R.S. Received April 5 , 1866 . The instructions for levelling from the Mediterranean to the Dead Sea having been received after the party had arrived at Jerusalem , it was thought best to level in the first place from Jerusalem to the Dead Sea during the cool months , and to complete the line to the Mediterranean at Jaffa , when the party were on their way home . But in describing the line levelled , we may assume that it was made direct from Jaffa to the Dead Sea . The line selected was that which runs across the maritime plain direct from Jaffa to Lydda , three miles beyond which , on the road to Beth Horon , the line turns to the right by Jimsu , Birfileeah , and Beit Sira ; and from thence up the Wady Suleiman to El Jib , where it again joins the old Roman Road from Lydda , by Beth Horon to Jerusalem . But at about 1 mile on the north road from the Damascus Gate , the line turns to the eastward over Mount Scopus , where it reached the altitude of 2724 feet , the height of the top of the large cairn on it . This was the highest point crossed between the Mediterranean and the Dead Sea . From Mount Scopus the line follows the high ground to the Mount of Olives , and thence takes the road down to Bethany , and , following the road by Khan Hladhur to near Jericho , the line turns to the right within about a mile of the latter place , and was carried thence across the plain bordering the Dead Sea to a point opposite a small island in the sea itself . [ May 3 , 128 Throughout the entire length of this line bench marks ( ) have been cut at intervals , wherever it was practicable , on the fixed rocks , or on permanent objects . The following is a list of the bench marks , with the distances between them : List of the Bench marks made in levelling the line from the Mediterranean to the Dead Sea in March , May , and June 1865 . No. Pla 'ce . Distance , in Miles and Links . Altitude . Where cut . Remarks . Jaffa ... ... ... ... ... ... 0 ... ... ... ... ... ... ... ... ... ... ... ... . , ... ... ... ... ... ... . Yazur ... ... ... ... ... . . Bethdagon ... ... ... ... Sephoneya ... ... ... ... ... ... ... ... . Lydda ... ... ... ... ... ... Lydda ... ... ... ... ... ... Jimzu ... ... ... ... ... ... , , ... ... ... ... ... ... , ) ... ... ... ... ... . . , , - ... ... ... ... ... ... , , ... ... ... ... ... .* , , ... ... ... ... ... ... , , ... ... ... ... ... . , ... . . ' ... ... ... ... , ... ... ... ... ... ... , ... ... ..o ... oo ... . , ... ... ... ... ... ... . . 00 1490 0 7972 1 5831 3 7656 5 5843 7 3157 9 6495 11 5922 14 0358 14 5194 15 1714 15 6495 16 4284 17 0548 18 0479 '18 7527 19 5196 21 7893 25 7849 26 5121 27 3392 30 3428 30 7617 33 5560 37 1670 feet 3-800 31-080 31-225 55-735 85-405 91-435 126-540 143-630 164-770 248-630 411-605 478-725 549-000 573-035 517-520 650-075 819-180 747-865 751-105 1,157-530 1,251-470 1,423-015 2,064-945 2,258-250 castle wall ... ... ... town wall ... ... ... on fountain ... ... on a well ... ... ... on a well ... ... ... on a well ... ... ... on a wall ... ... . . on a tree ... ... ... ... garden wall ... ... ... west angle of well. . on rock ... ... ... ... on rock ... ... ... ... on rock ... ... ... . on rock ... ... ... ... on rock ... ... ... ... on rock ... ... ... . . on rock ... ... ... ... on rock ... ... ... ... on rock ... ... ... ... on rock ... ... ... ... on rock ... ... ... ... on wall ... ... ... ... On rock ... ... ... ... on rock ... ... ... ... 2,419-505 on rock ... ... ... . . 2,681-915 on stone ... ... ... . . On the wall , 3800feet above level of the Mediterranean . On gate at entrance to town . On the fountain near Jaffa . At west side of road . At the east end of the village . At the west end of the village . In Sephoneya village , near lone tree . On a lone tree on maritime plain . At east end of Lydda village . Half a mile west of Jimzu village . In road at thrashingfloor , Jimzu . On side of road , top of hill . On road , top of hill . West side of road . Side of road , and junction of Wady . At junction of road to Birfilleya . East side of road . On side of road . In centre of road . On side of road . On side of road . Corner of garden wall in Wady . South side of stream . Entrance to Wady Suliemanl . East side of road . Near trigonometrical station , Jerusalem Survey . 1 . 2 . 3 . 4 . 5 . 6 . 7 . 8 . 9 . 10 . 11 . 12 . 13 . 14 . 15 . 16 . 17 . 18 . 19 . 20 . 21 . 22 . 23 . 24 . 25 . 26 . TABLE ( continued ) . Distance , No. Place . in Miles Altitude . Where cut . Remarks . and Links ... ... -1_- ... ---^ , -I_ _ _ , ... ... ... ... ... ... . Mount Scopus ... ... . ? ... ... ..o ... . Mount Olivet ... ... Ascension ... ... ... ... Bethany ... ... ... ... ... 37 4078 37 6345 38 0612 38 1896 38 5086 38 6530 39 0236 39 1721 39 1731 39 2794 40 2409 ... ... ... ... ... 40 4225 ... ... ... ... ... 41 0148 Well of the Apostles. . Khan Hadhur ... ... , ... ... . Old Aqueduct , ... ... I ... ... . , ... ... . 41 6063 42 2457 43 1606 44 0032 45 0375 47 0498 47 3127 48 5296 50 2545 51 0706 52 7866 53 5174 54 0339 54 4465 ... ... 62 2514 feet 2,685-390 2,648-545 2,688-700 2,715-795 2,662-905 2,603-875 on stone ... ... ... . . on rock ... ... ... . . on cistern ... ... ... on rock ... ... ... ... on pillar ... ... ... ... on stone ... ... ... ... 2,623-790 on wall ... ... ... ... 2,662-500 on rock ... ... ... ... 2,665-080 surface ... ... ... ... ... 2,643-220 on house ... ... ... . . 2,281-825 on rock ... ... ... ... 2,208-755 on rock ... ... ... ... 2,018-350 1,519-615 1,351-845 1,163-060 1,039-145 902-515 654-190 776-130 870-590 537-010 451-510 89715 99'035 209 890 477-045 -1,273'215 ... ... 62 2965 -1,292-135 on rock ... ... ... ... on wall ... ... ... . . on rock ... ... ... . . on rock ... ... ... . . on rock ... ... ... ... on rock ... ... ... ... on stone ... ... ... ... on rock ... ... ... ... on rock ... ... ... ... on rock ... ... ... ... on rock ... ... ... ... on rock ... ... ... . on rock ... ... ... ... on rock ... ... ... . on rock ... ... ... ... on stone level of sea ... ... . . In centre of road . In centre of road . East side of road . Near G-ustam Pole . On east side of road . West side of road , near junction . West side of road . Near summit of Mount Olivet . At trigonometrical station . South side of road . Trigonometrical line , 13ethany to Scorpion . Near well , Bethany village . North side of road at junction of fences . Base of Bethany Hill . South side of road . South side of road . North side of road . Near junction of Nebi Musa . Opposite trees in valley . At the top of the hill . , At entrance to cave opposite Khan . On side of road . At top of hill . On side of road . On side of road . North side of road . In centre of road opposite house . Sunk on the beach of the Dead Sea opposite island . Height of Dead Sea on the 12th March , 1865 . At the distance of 3miles beyond Khan Hadhur , on the road to Jericho , the level of the Mediterranean was crossed , and from thence towards the Dead Sea the levels are marked with the negative sign . On the 12th of March , 1865 , the party reached the Dead Sea , when its level was found to be 1292 feet below the level of the Mediterranean- ; but from an examination of the drift wood on the shore , it was ascertained that at some time of the year , probably after the winter freshets , the water rises 2 } feet higher , which would make the least depression 1289'5 . 27 . 28 . 29 . 30 . 31 . 32 . 33 . 34 . 35 . 36 . 37 . 38 . 39 . 40 . 41 . 42 . 43 . 44 . 45 . 46 . 47 . 48 . 49 . 50 . 51 . 52 . 53 . 54 . 55 . From inquiry amongst the Bedouins and European residents in Palestine , it was ascertained that during the early summer the level of the sea falls at least 6 feet below the level at which it stood on the day the levelling was taken , which would make the depression 1298 feet ; and we may conclude that the maximum depression at no time exceeds 1300 feet . Lieut. Symonds , R.E. , in 1841 , made the depression 1312'2 feet . The soundings in the Dead Sea by Lieut. Vignes of the French Navy , gave a maximum depth of 1148 feet , making the depression of the bottom of the Dead Sea 2446 feet below the level of the Mediterranean . The soundings in the Mediterranean , midway between Malta and Candia , by Captain Spratt , R.N. , gave a depth of 13,020 feet , or a depression of the bottom five times greater than that of the bottom of the Dead Sea . The levelling was executed by two independent observers , and from a comparison of the two sets of levelling , it is certain that the levels have been obtained with absolute accuracy to within 3 or 4 inches . The establishment of a chain of levels across the country with bench marks cut on so many points , cannot but prove of the utmost importance for any future investigations , or for any more extended surveys in Palestine , such as are contemplated by the Society which has been formed since this survey was made , " for the accurate and systematic investigation of the archreology , the topography , the geology , and physical geography , &c. of the Holy Land , for Biblical illustration . " For the survey of Jerusalem itself , it was of the utmost importance , as it enabled us to connect all the levels in and about the city with the level of the Mediterranean , and to harmonize , so to speak , all the levels which have been taken .

112601

3701662

Note on the Amyl-Compounds Derived from Petroleum

131

132

Proceedings of the Royal Society of London

C. Schorlemmer

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10.1098/rspl.1866.0031

http://www.jstor.org/stable/112601

Chemistry 2

Tables

Chemistry

II . " Note on the Amyl-Compounds derived from Petroleum . " By C. SCHORLEMMER . Communicated by Professor RoscoE . Received April 26 , 1866 . In a former communication I have shown that the hydride of heptyl obtained from petroleum has a higher specific gravity than its isomers ethyl-amyl , and hydride of heptyl from azelaic acid . The same is the case with their derivatives , and some of these isomeric compounds also show considerable differences in their boiling-points * . I could not compare the different heptyl-compounds which I prepared with those of heptyl-alcohol formed by fermentation , as the latter substance is very little known , and I therefore considered it interesting to compare the amylcompounds from fusel-oil with those obtained from petroleum . From the latter substance I prepared a considerable quantity of pure hydride of amyl , which boiled constantly at 33 ? -35 ? C. ; and I did not succeed in lowering the boiling-point any further . From this hydride other amylcompounds were obtained in exactly the same way as the heptyl-com* Proc. Roy . Soo . vol. xiv . p. 464 . 131 TOL . XV . pounds . Pure amyl-compounds from fusel-oil were also prepared with the greatest care , and their specific gravities and boiling-points compared , under exactly the same circumstances , with the compounds prepared from petroleum . The results of this investigation are contained in the following Table : Amyl-Compounds . Fromfusel oil . From pfetroleum . Boiling-point . Specific gravity . Boiling-point . Specific gravity . C5H12 ... 34 ? C. 0-6263 at 17 ? C IiTi CI 1010 C. 0-8750 at 20§ 101 ? C. 0-8777 at 20 ? Ct5Ho O0 140 ? C.* 08733 at 15§ 140 C. ? 0-8752 at 15 ? C , 12 O 132 ? C. 0 '8148 at 14§ 132 C. 0-8199 at 14 ? . It appears from this Table that the boiling-points of the same compounds agree perfectly , and that the specific gravities show only very small differences , those of the substances obtained from petroleum being a little higher . This is easily accounted for by an admixture of higher boiling compounds , which towards the end of the distillation raise the boilingpoints a little , and which cannot be removed completely , even by longcontinued rectifications . The amyl-compounds from petroleum and those from fusel-oil are therefore identical .

112602

3701662

On a New Series of Hydrocarbons Derived from Coal-Tar

132

136

Proceedings of the Royal Society of London

C. Schorlemmer

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http://dx.doi.org/10.1098/rspl.1866.0032

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112602

10.1098/rspl.1866.0032

http://www.jstor.org/stable/112602

Chemistry 2

Thermodynamics

Chemistry

III . " On a New Series of Hydrocarbons derived from Coal-tar . " By C. SCHORLEMMER . Communicated by Professor RoscoE . Received April 26 , 1866 . The light oils obtained by the destructive distillation of Cannel-coal at a low temperature , contain , besides the hydrocarbons of the marsh-gas and benzol series , other substances , which are attacked by concentrated sulphuric acid . If the oil , which has been repeatedly shaken with this acid , be subjected to distillation , the hydrocarbons which are unacted upon volatilize first , and a black tarry liquid , equal in bulk to about half the crude oil , remains behind t. On heating this residue more strongly , a brown oil , having an unpleasant smell , comes over at about 200 ? C. ; the temperature rises gradually up to 300 ? C. , and at last a black pitchy mass is left in the retort . Even after repeated rectifications the oil always leaves a solid black residue behind , and it was only by continued fractional distillations over solid caustic potash and metallic sodium , that I succeeded in isolating substances possessing nearly a constant boiling-point and volatilizing almost completely . The compounds which I thus obtained from Cannel-coal oil , boiling below 120 ? C. , are hydrocarbons of the general formula ( C , , H_2)2 , as the following analyses and determinations of the vapour-densities show:* ' The boiling-point of acetate of amyl is given very differently by different observers ( Cahours found 125 ? , Landolt 133-134 ? ; Pogg . Ann. vol. cxxii . p. 554 ) . M[y observation agrees perfectly with that of Wanklyn ( Chem. Soc. Journ. ( 2 . ) iii . p. 30 ) . t Journ. Chem. Soc. vol. xv . p. 420 . ( 1 ) C2 1H20 boiling-point 210 ? C. ( a ) 0'262 substance gave 0'840 carbonic acid and 0'290 water . ( b ) 0'1978 substance gave 0'635 carbonic acid and 0'2195 water . Calculated . Found . a-'-- , -b.a . C2 ... ... 144 87-8 87-44 87-55 H20 ... . 20 12'2 12*30 12*32 164 100'0 99*74 99'87 Globe with air ... ... ... 5'547 Temperature of air ... ... 17 ? C. Globe with vapour ... ... 5'730 Temperature on sealing. . 250 ? C. Capacity of globe . , ... . 65'0 cubic centims. Calculated . Found . 6*68 6'98 The residue in the globe had a brown colour , the oil not being completely volatile ; this accounts for the difference between the calculated and found vapour-densities . ( 2 ) C14 H2 , , , boiling-point 240 ? . 0'107 substance gave 0'343 carbonic acid and 0'1195 water . Calculated . Found . C14 . 168 875 87842 42 ... . 24 12'5 12-40 192 100'0 99'82 ( a ) Weight of globe ... ... . . 3.3354 Temperature of air ... ... 10 ? *5 C. Globe with vapour ... ... 3'5745 Temperature on sealing. . 280 ? C. Capacity of globe ... ... 676 cub. centims. ( b ) Weight of globe ... ... . . 3*286 Temperature of air ... ... 7 ? C. Globe with vapour ... ... 3*4665 Temperature on sealing. . 270 ? C. Capacity of globe ... ... 552 cub. centims. Found . Calculated . a. b. 6'65 70-6 7'02 The liquid remaining in the globe had also in both cases a brown colour . ( 3 ) C,1 H^8 , boiling-point 280 ? C. 0 152 substance gave 0'4885 carbonic acid and 0-174 water . Calculated . Found . C , , ... ... 192 87-27 87-11 H28 ... ... 28 12 73 12'72 220 100'00 99'83 N2 1866 . ] 133 These hydrocarbons are colourless , oily , strongly refracting liquids , lighter than water , and possessing a faint peculiar smell , resembling that of the roots of Daucus carota or Pastinaca sativa . I have obtained them in small quantities only , and could study their reactions therefore only incompletely . They combine with bromine with a hissing noise , and if the reaction is not moderated , the liquid blackens and hydrobromic acid is evolved ; but by keeping the substance well cooled , and by adding the bromine very carefully , nearly colourless , heavy , oily , sweet-smelling bromine-compounds are obtained , without the formation of hydrobromic acid . These are very easily decomposed by heating ; charry matter separates out , and hydrobromic acid is given off even below the boiling-point of water . From the hydrocarbon C 4H 2 alone I obtained a sufficient quantity of the bromide for analysis . 0'3715 substance gave 0 3605 bromide of silver and 0 0123 metallic silver . Calculated for Found . C14 H24 Br2 . 45'45 per cent. Br . 43'7 per cent. Br . As it was impossible to purify the small quantity of bromide , the difference between the found and calculated quantities is easily accounted for . Concentrated nitric acid dissolves these hydrocarbons , much heat being evolved ; on diluting the acid solution with water , yellow , heavy , thick oily nitro-compounds separate , which have a faint but peculiarly unpleasant smell . By heating these nitro-compounds with tin and hydrochloric acid , a portion is converted into a black tarry mass , and the solution contains a considerable quantity of chloride of ammonium , and a small quantity of a hydrochlorate , which can be obtained as a crystalline deliquescent mass by evaporating in vacuo . On concentrating the solution in the air , decomposition takes place , a violet substance being formed . By adding caustic potash to the solution of the hydrochlorate , a dark oily base separates , which quickly oxidizes into a black tarry mass . Platinic chloride produces at first no precipitate in the concentrated solution of the hydrochlorate , but after a few minutes a dark violet tar separates . I could not succeed in obtaining crystallized double chlorides of tin or zinc , If these hydrocarbons are heated with a concentrated solution of bichromate of potassium and sulphuric acid , carbonic acid is evolved , a strongly acid liquid , on which an oily layer swims , distils over , a resinous substance remaining in the retort . As I did not'obtain any of the pure hydrocarbons in sufficient quantity to study their separate products of oxidation , I took all that remained , together with the intermediate distillates , and the oil boiling above 280 ? C. , which had been previously well purified by rectification over sodium . After oxidation , the distillate was neutralized with carbonate of sodium , the oil being left undissolved . This neutral oil , which has an ethereal smell , and boils between 200 ? and 300 ? C. , gave on analysis 84'9 per cent. C and 11-8 per cent. I ; it consists , therefore , of non-oxidized hydrocarbons , containing a small quantity of an oxygencompound . The solution of the sodium-salt was evaporated on the waterbath , the residue distilled with diluterl sulphuric acid , and the distillate rectified . It smelt strongly of acetic acid , and also slightly of butyric acid . By neutralization with carbonate of sodium , a crop of crystals of acetate of sodium was obtained , which were converted into the crystallized silversalt . 0-1335 of this salt gave 0'861 of silver . Calculated for Found . C2 13 Ag 02 . 64'67 per cent. Ag . 64'50 per cent. Ag . The syrupy mother-liquor of the sodium-salt gave , with nitrate of silver , a white precipitate , which , on boiling the liquid , decomposed with effervescence and separation of metallic silver , showing the presence of formic acid ; from the filtered liquid small warty crystals of a silver-salt separated . 0'1314 of this salt gave 0'842 of silver , or 64'1 per cent. Ag . The mother-liquor gave on evaporation again crystals of acetate of silver . 0'2196 gave 0'1418 silver , or 64'56percent . The volatile acids produced by the oxidation of the hydrocarbons are therefore carbonic acid , acetic acid , formic acid , and perhaps a trace of an acid richer in carbon . The resinous substance left in the retort is an acid which dissolves in caustic potash , and is precipitated from this solution as a brown greasy substance , easily soluble in alcohol . The alcoholic solution , neutralized with ammonia , gave , with nitrate of silver , a white flocculent precipitate of a silver-salt , which dried into a brown resinous mass , not fit for analysis . As these hydrocarbons were obtained by the action of sulphuric acid on coal-tar oils boiling below 120 ? , and as they differ by C , H1 , it appears to me almost certain that they are polymers of the hydrocarbons of the acetylene series , C , H2 , -2 , formed in the same way as diamylene is formed , by treating amylene with sulphuric acid . The products of oxida . tion are also in accordance with this view . In order to test this theory , I have made some experiments with the two isomers C6 Ho1 , namely , diallyl and hexoylene . By acting with sulphuric acid on these compounds , I obtained , besides large quantities of tarry matter , polymeric modifications boiling above 200 ? , having a smell similar to the hydrocarbons described above , giving also similar nitro . compounds ; but the quantities which I got were not large enough for a more exact examination . The sulphuric acid which was used to purify the coal-tar oils contains an organic substance in solution , which can be isolated by neutralizing the acid liquid with carbonate of calcium , filtering , evaporating to dryness in the water-bath , extracting the residue with alcohol , and evaporating the alcoholic solution . It forms a yellow amorphous mass , which has a faint , bitter , and astringent taste . A substance with exactly the same properties was obtained from the acid which was used to act upon the hydrocarbons C Hl , . I am at present engaged upon experiments to isolate the hydrocarbons Cn H12n-2 contained in coal-tar .

112603

3701662

The Calculus of Chemical Operations; Being a Method for the Investigation, by Means of Symbols, of the Laws of the Distribution of Weight in Chemical Change. Part I.--On the Construction of Chemical Symbols. [Abstract]

136

139

Proceedings of the Royal Society of London

B. C. Brodie

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6.0.4

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http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112603

http://www.jstor.org/stable/112603

Formulae

Chemistry 2

Mathematics

IV . " The Calculus of Chemical Operations ; being a Method for the Investigation , by means of Symbols , of the Laws of the Distribution of Weight in Chemical Change . Part I.-On the Construction of Clhemical Symbols . " By Sir B. C. BRODIE , Bart. , F.R.S. , Professor of Chemistry in the UTniversity of Oxford . Received April 25 , 1866 . ( Abstract . ) In chemical transformations the absolute weight of matter is unialtered , and every chemical change , as regards weight , is a change in its arrangement and distribution . Now this distribution of weight is subject to numerical laws , and the object of the present method is to facilitate the study of these laws , by the aid of symbolic processes . The data of the chemical calculus , as indeed of every other application of symbols to the investigation of natural phenomenia , are supplied by observation and experiment ; and its aim is simply to deduce from these data the various consequences which may be inferred from them . The provinice of such a method commences where that of experiment terminates . This part comprises the consideration of the fundamental principles of symbolic expression in chemistry , and also the application of the method to the solution of perhaps the most importanit of all chemical problems , ramely ; the questioni of the true composition , as regards weight , of the units of chemical substances . Section I. In the first section certain definitions are given of those weights and relations of weight , of which the svmbols are subsequently considered . It may be regarded as containing an analysis of the subject of chemical investigation . The definitions are of " a chemical substance , " " a weight , " " a single weight , " " a group of weights , " " identical weights , " " a compound weight , " " a simple weight , " and " an integral compound weight . " The unit of a cheinical substalnce is defined as that weight of the substance which at 00 Centigrade , and 760 millims. pressure and in the condition of a perfect gas , occupies the volume of 1000 cubic centimetres . This volume is termed the unit of space . Section II . The second section treats of symbolic expression in chemistry . A " chemnical operation " is defined as an operation of which the result is a weight . These operationis are symbolized by letters , x , y , &c. An interpretation is assigned to the symbols + and - , as the symbols of aggregation and segregation , that is , of the mental operations by which groups are formed . The symbol _ is selected as the syinbol of cheemical identity ; the symbol 0 as the symbol of the absence of a weight , this symbol being identical with x-x . The symbol ( x+x ) is the symbol of two weights collectively considered , and as constituting a whole . The symbols xy and x are selected as the symbols of compound weights , yI and it is proved that with this interpretation these symbols are subject to the commutative and distributive laws , CCy=YXI x ( y + Y1)= xy + xy1 , and also to the index law , ^ , Pzq = zP+17 Section III . treats of the properties and interpretation of the chemical symbol 1 , which is selected as the symbol of the subject of chemical operations , namely , the unit of space . With this interpretationl the chemical symbol 1 has the property of the numerical symbol 1 given in the equation xl =X . Section IV . Chemical symbols are here shown to be subject to a special symbolic law , given in the equation xy=x+y . This property , by which chemical symnbols are distinguished from the symbols employed in other symbolic methods , is termed the " logarithmic " property of these symibols . A consequence of this property is that 0=1 , and that any number of numerical symbols may be added to a chemical function without affecting its interpretation as regards weight . Section V. relates to the special properties of the symbols of simple weights , which are termed prime factors , from their analogy to the priime factors of numbers . These symbols differ , however , from these factors in that , like the numerical symbol 1 , they are incapable of partitioni as well as of division , which is a consequence of the condition xy=x+y . The symbol of the unit of a chemical substance , expressed as a function of the simple weights of which it consists , is identical with the.symbol of a whole riumber expressed by means of its prime factor , a " , V , 1"2 ... . A general method is given for discovering the prime factors of chernical symbols . Section VI . is on the construction of chemical equations from experimental data . Section VII . On the expression of chemical symbols by means of prime factors in the actual system of chemical equations . The object of this section is to prove that the units of weight of chemical substanices are integral compound weights , and to discover the simplest expression for the symbols which is consistent with this assumptioni . Such an expression cannot be effected unless some one symbol be determined from external considerations . The unit of hydrogen , therefore , is assumed to consist of one simple weight , its symbol being expressed by one prime factor , a , which is termed the viodulus of the symbolic system . This assertion is the expression of a hypothesis which may be proved or disproved by facts , and the consequences of which are here traced . The symbols of the elements are considered in three groups . 1 . The symbols of the elements of which the density in the gaseous conditionl can be experimentally determined , and which form with one another gaseous combinations . 2 . The symbols of carbon , boron , and silicon . 3 . The symbols of other elements , which are determined with a certain probability by the aid of the law of Dulong . For the method of constructing these symbols , which depends upon the solution in whole numbers of certain simple indeterminate equations , we must refer to the memoir itself . The following symbols may serve as an illustration of the general results : Absolute Relative Name of substance . Prime factor . weight in weight . grammes . a 0-089 1 0-715 8x1 542 17 25 v 0-581 65 ci 1-805 15 0-536 6 Symbol . Hydrogen ... ... ... ... a0 089 1 Oxygen ... ... ... ... 42 1.430 16 Water ... ... ... ... a 0 804 9 Chlorine . , ... ... ... . aX2 3-173 35-5 Hydrochloric acid ... ... ... ... aX 1-631 18-25 Oxide of chlorinie ... * X ... ax2Z 3-888 43 5 Hypochlorous acid ... ... ... ax 3 2-346 26-25 Teroxide of chlorine ... ax 21 5 319 59 5 Chlorous acid ... ... ... ... ... ax 23 062 34 25 Chloric acid ... ... ... ... aX 3 3-777 42-25 Nitrogen ... ... ... ... ... ... av2 1251 14 Ammonia ... ... ... ... ... . a2v 0 760 85 Protoxide of nitrogen ... ... ... ... av24 1966 22 Nitrite of ammoniun ... ... a3v2V2 2-860 32 Chloride of ammoniumn ... ... ... . . ca3vx 2 391 26-75 Phosphorus ... ... . . a4 5-541 62 Phosphide of hydrogen ... ... ... a 2o 1*519 17 Pentachloride of phosphorus ... ... . a 35 9 319 104-25 Tercbloride of phosphorus ... ... a20X3 6-145 68-75 Oxychloride of phosphorus ... ... a 6-869 76-75 Carbon ... ... ... ... ... ... . ICY 0-536+y 6+y Acetylene ... ... ... ... alc 1 161 13 Marsh-gas. . a2I 0 704 8 Alcohol ... ... ... ... a 2-056 23 Ether ... ... ... ... ... a r ' 3 308 37 Acetic anhydride ... ... . a32K22 4-559 51 Acetic acid ... ... 2C2 20682 30 Trichloracetic acid ... ... . a2%3gC2t2 6-146 68-75 Hydrocyanic acid ... ... ... ... avrc 1 207 13-5 Cyanogcn ... ... . av2x2 2-324 26 Section VIII . Certain apparent exceptions are considered , in which it is not found possible to express the symbols of chemical substances by means of an integral number of prime factors , consistently with the assumption of the modulus a.

112604

3701662

On the Motion of a Rigid Body Moving Freely about a Fixed Point. [Abstract]

139

144

Proceedings of the Royal Society of London

J. J. Sylvester

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6.0.4

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http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112604

http://www.jstor.org/stable/112604

Fluid Dynamics

Formulae

Fluid Dynamics

I. " 'On the Motion of a Rigid Body moving freely about a Fixed Point . " By J. J. SYLVESTER , LL. D. , F.R.S. Received April 26 , 1866 . ( Abstract . ) The nature of the present brief memoir will be best conveyed by my giving a succinct account of the principal results which it embodies , in the order in which they occur . The direct soluition , in its present form , of the important problem of the motion of a rigid body acted on by no external forces , originating in the admirable labours of Euler , has received the last degree of finish and completeness of which it is susceptible from the powerful analysis of Jacobi ; in one sense , therefore , it may be said that the discussion is closed and the question at an end . Notwithstanding this , in the mode of conceiving and representing the general character of the motion , there are certain circumstances which merit attention , and which may be expressed without reference to the formulw in which the analytical solution is contained . Poinsot 's method of representing the motion by means of his so-called " central ellipsoid " has passed into the every-day language of geometers , and may be assumed to be familiar to all . The centre of this ellipsoid is supposed to be stationary at the point rounid which any given solid body is turning ; its form is determined when the principal moments of inertia of that body are given , and it is suipposed accurately to roll without sliding on a fixed plane whose position depends on the initial circumstances of the motion . The associated free body is conceived as being carried along by the ellipsoid , so that its path in space , its continuous succession of changes of position , is thereby completely represented ; but no image is thus presented to the mind of the time in which the change of position is effected . I show how this defect in the representation may be remedied , and the time , like the law of displacement , reduced to observation by a slight modification of the apparatus of the central ellipsoid or representative nucleus , as it will for the moment be more convenient to call it . To steady the ideas , imagine the fixed invariable plane of contact with the nucleus to be horizontal and situated under it ; nOw colnceive a portion of its upper surface , say the upper half , to be pared away until it assumes the form of a semiellipsoid confocal to the original surface , and that an indefinitely rough plate always remaining horizontal , bIut capable of turning in its own plane round a vertical axis , which , if produced , would pass through the centre of the ellipsoid , is placed in contact with this upper portion ; as the nucleus is made to roll with the under part of its surface upon the fixed plane below , the friction between the upper surface and the plate will cause the latter to rotate round its axis , for the niucleus will not oinly roll upon the plate above , but at the same time have a swilnging mnotion roulnd the vertical , which will be communicated to the plate . I prove , by an easy application of the theory of confocal ellipsoids , that the time of the free body passing from one position to another will be in a constaint ratio to this miotion of rotation , which may be measured off upon an absolutely fixed dial face immediately over the rotating-plate ; and furthermore I show that the relationi between the angular divisions of this dial and the timiie depends only upon the spinnilg force which may be supposed to set the free body originially in motion , so that it will hold the same , at whatever distance , by a preliminary adjustment , the rotating-plate may be supposed to be set fromii the fixed horizontal plane . Thus , then , we may realize a complete kinematical image of all the circumstances of the motion of a free rotating body , and reduce to a purely mechanical measurement the determination of an element hitherto unrepresented , but in reality the most important of all , viz. the time . I then proceed to point out a very singular and hitherto unnoticed dynamicazl relation between the free rotating body and the ellipsoidal top , as I shall now prefer to call Poinsot 's central ellipsoid , because I imagine it set spinning like a top upon the invariable plane in contact with it and left to roll of its own accord , the friction between it and the plane being supposed adequate to prevenlt all sliding . I start with supposing that the density of the top follows any law whatever , and call its principal moniciits of inertia A , B , C , its semiaxes a , 6 , c , the relationis betweeni these six quantities being left arbitrary . It is easy to establish that , if a rotating body be acted oln by any forces which always meet the axis about which it is at any instant turning , the vis viva will remain unaffected by their action ; this will be the case in the present instance with the pressure and friction of the invariable plane , the only forces concerned , as we may either leave gravity out of account altogether or suppose the cenitre of gravity of the top to be at the centre of the ellipsoid , which will come to the same thing . By aid of this principle , conjoined with the two conditions to which the angular velocities of the associated free body are known to be subject , it is easy to infer that the velocities of this body and its representative top will , throughout the motion , remain in a constant ratio , or , if we please , equal to one another , provided that AllXIaa 612 b c4 : where X is an arbitrary constant . If , now , we revert to the natural supposition of the top beirig of uniform denlsity , it is well known that A : B : C : : b2+c2 : c2+a'2 : a'+ b2 and these ratios may be identified with those above ( although this would not at the first blush be supposed to be the case ) by giving a suitable value to the arbitrary constant X. Thus , then , Poinsot 's central ellipsoid supposed of uniform density and set spinning upon a roughened inivariable plane will represenit the motion of a free rotating solid , not in space only but also in time ; the body and the top may be conceived as continually moving round the same axis and at the same rate at each moment of time * . The problem of the top is completed in the memoir by applying the general Eulerian equations to determine the friction and pressure , a process which involves some rather operose but successfully executed algebraical calculations . I next proceed to account analytically for the kinematical theory established at the outset of the memoir , and in . doing so am necessarily led to give greater completeness to it , and at the same time an extension to the existing theory of confocal surfaces of the second order , by introducing the complementary motion of surfaces that I call contrafocal to one another : confocal ellipsoids are those the differences between the squiares of whose corresponding principal arcs are all three the same ; contrafocal ellipsoids I define to be those the sums of the squares of whose corresponding arcs are the same . Any two bodies whose central ellipsoids are either confocal or contrafocal I term related-correlated in the onie case , contrarelated in the other , and I show that the kinematical construction in question is only another renidering of the first of the propositions hereini subjoined concerning bodies so related . 1st . If two correlated bodies be placed with their principal axes respectively parallel and be set spinning by the same impulsive couple , they will move so that the corresponding axes of the one and the other body will continue always equally inclined to the axis of the couple , and their original parallelism at any instant may be restored by turnling one of the bodies about this last-named axis through an angle proportional to the time elapsed since the commencement of the motion . Virtually , this amounts to saying that the difference between the displacement of two correlated bodies subject to the same initial impulse is equivalent to a simple uniform motion about the invariable line . 2nd . So , in like manner , if the bodies be contrarelated , the sum of their displacements is equivalent to a simple uinifornm motion about such line . 3rd . In either case alike , the difference between the squared angular velocities of the related bodies is constant throughout the motion . From these propositions it follows that for all practical intents and purposes the motion of any body is sufficiently represented by the motion of any other one correlated or contrarelated to it . To a spectator on the invariable plane the apparent motion of one rotating body may be made identical with that of any other related one by merely making the plane on which he stands turn uniformly round a perpendicular axis . It becomes natural , then , to ascertain whether there is not always some one or more simplest form or forms which may be selected out of the whole couple of infiinite series of related bodies , which may conveniently be adopted as the exemplar or type of all the rest . Obviously , the best suited for such purpose will be a body reduced to only two dimensions , in other words an indefinitely flattened disk , provided that it be possible in all cases to find a disk cor related or contrarelated to any given solid* . The algebraical investigation for ascertaining the existence of such disk is the same whichever species of relationl is made the subject of inquiry , and leads to the construction of three quadratic equations corresponiding to the respective suppositions of the original body becoming indefinitely flattened in the direction of each of its three principal axes in turn ; so that for a moment it might be supposed that the number of disks fulfilling the required condition could , according to circumstances , be zero , two , four , or six . But on closer examination , and bearing in mind that niegative equally with imaginary moments of inertia are inadmissible , it turns out that there are always two such disks , and no more ( except in the case of two of the moments of inertia being equal when the solution becomes unique ) . Of these two disks , one will be correlated and the other contrarelated to the given body , and they will be respectively perpendicular to the axes of greatest and least moments of inertia . We have thus the choice between two methods of reduction to the type form , and this choice is not a matter of unimportance ( in nature nothing exists in vain ) ; for by means tbereof the motion of any given body subject to any initial conditions can be made to depend upon either at will of the two comprehensive cases ( Legendre 's 1st and 3rd ) to which the motion of a free rotating body is usually referred , so that the distinction between these two cases ( corresponding to the two species of Polhodes on either side of the " Dividing Polhode , " according to Poinsot 's method of exposition ) is virtuially abrogated . From the preceding theory , it follows ( as also may be made to appear alike from an attentive synoptic view of the commonly received analytical formulae as from Poinsot 's theory of the associated " sliding and rolling cone " ) that in the problem of the motion of a free body , of whatever form and subject to whatever initial conditions one pleases , there enter but two arbitrary parameters . Calling A , B , A+ B the three moments of inertia of one or the other equivalent disks , L the magnitude of the impulsive couple , M the vis viva , these two parameters ( say p , q ) will be AL , BL ' ; if to them we add a quantity Mt t say r ( where t is the terms reckoned , as it may be , from an intrinsic epoch as explained in the memoir ) , all other elements of the motion , as the total or partial velocities and the angles , whatever they may be , selected to determine the position of the rotating body become known functions of these three quantities , p , q , r , and may be reduced to tables of triple entry , or be graphically represented by a few charts of cuirves ; and it should be noticed that p , the smaller of the two parameters p , q , will be always necessarily included between o and 1 , and that the other parameter q may , by a due choice of the species of reduction adopted , beforcibly retained within the same limits . The five quantities o , p , q , 1 , p+q will then form an ascending series of magnitudes subject only to the liability of the middle term q to become equal to 1 on the one hand , or to p on the other : q becoming unity corresponds to the case of the so-called " Dividing Polhode , " Legendre 's 2nd case ( " cas tre 's remarquabte " ) ; and q becoming equal to p is of course the case of the body itself , or its " central ellipsoid , " becoming a figure of revolution , in which case the motion is practically the same as that of a uniform circular plate . Besides these two exceptional cases , the only singular cases properly so called , the quinary scale of magnitudes just exhibited serves to indicate all the more remarkable cases ( requiring or inviting particular methods of treatment ) which can present themselves in the theory . These may be distinguished into special cases , which arise from any two consecutive terms becoming ( to use Prof. De Morgan 's expressive term ) subequal , i. e. differing from one another by a quantity whose square may be neglected , and double special cases , which arise when any three consecutive terms become subequal ; all of which , together with peculiar subcases appertaininJg to the double special class , perhaps deserve more thorough examination than may have been hitherto accorded to them . I conclude the memoir with pointing out the place which this problem of Rotation appears to me to occupy in dynamical theory , as belonging to a natural and perfectly well defined group of questions , of which the motion of a body attracted to two fixed centres and the renownied problem of three bodies acted on by their mutual attractions are conspicuous instances . This group is characterized by the feature that , as regards them , equations of motion admit of being conistructed , from which not only the element of time , as in ordiniary mechanical problems , but also an element of absoluite space is shut out ; supposing the equations thus reduced by two in the number of the variables to have been integrated , Jacobi 's theory of the last multiplier serves to reduce both the excluded elements to quadratures and thus to complete the solution . I notice that whilst the time may fairly be said to be eliminated , the space element may be more properly said to undergo the negative process , if it may be so called , of ab-limination ; it is not introduced into and then expelled from , but prevented from ever making its appearance at all in the resolving system of differential equations . It is from the study of one of these allied but more difficult questions that the present memoir has taken its rise as a collateral inquiry and elucidatory digression .

112605

3701662

On Appold's Apparatus for Regulating Temperature and Keeping the Air in a Building at Any Desired Degree of Moisture

144

146

Proceedings of the Royal Society of London

J. P. Gassiot

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0035

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112605

10.1098/rspl.1866.0035

http://www.jstor.org/stable/112605

Measurement

Thermodynamics

Measurement

II . " On Appold 's Apparatus for regulating Temperature and keeping the Air in a Building at any desired degree of Moisture . " By J.P. GASSIOT , Esq. , V.P.R.S. Received May 3 , 1866 . Those Fellows of the Royal Society who were acquainted with the late Mr. John George Appold , have often expressed their admiration at the various scientific arrangements which he from time to time adapted to his dwellinghouse in Wilson Street , Finsbury Square . However intense might be the frost of winter or the heat of summer , or the brilliancy of the gas with which his rooms were lighted , when once under his hospitable roof you enjoyed a pure and refreshing atmosphere . Much of this was undoubtedly due to the steam-power he always had at command connected with his business premises immediately adjacent to his dwelling-house , by which he could at any time force a current of fresh air at a given temperature into any of his rooms ; indeed Mr. Appold always contended that houses could not be made thoroughly comfortable as habitations without the aid of steam-power . But among the many of his arrangements to obtain equable temperature in rooms , there were also those that do not require the aid of steam-power , so seldom applicable in private dwellings , and which , being easy of adaptation , might be used in private houses with much advantage as regards the health and comfort of the inmates . I allude to his Automatic Temperature regulator , and to his Automatic Hygrometer ; and these instruments , as originally constructed by her late husband , and used for many years in their house , but now repaired and placed in perfect working order by Mr. Browning , Mrs. Appold has requested me to offer in her name to the President and Council of the Royal Society . She desires me to express a hope that they will oblige her by retaining them among the other scientific apparatus belonging to the Royal Society , as a mark of respect to the memory of one who always highly esteemed the honour he received when he was elected into that body in June 1853 . I annex a description and drawing of both instruments ( Plate VII ) . Appold 's apparatus for regulating the temperature of buildings automatically . This instrument consists of a glass tube having bulbs at each end . The 144 [ May 17 , tube is filled , as also about half of each bulb , with mercury ; the lower bulb containing ether to the depth of half an inch , which floats on the mercury . The tube is secured to a plate of boxwood , and supported on knife-edges , on which it turns freely . At the end of the plate , underneath the highest bulb , is a lever , to which a string is attached . This string is carried , by means of bell-cranks , to the supply-valve of a gas-stove , or the damper of a furnace . The instrument acts in the following manner:-Supposing the stove to be lighted and to have raised the temperature more than is required , the heat will convert a portion of the ether in the lower bulb into vapour . The expansion of this vapour drives a quantity of the mercury out of the bulb underneath it through the tube into the upper bulb . The end to which the mercury has been driven being thus rendered the heaviest falls , and motion being communicated by the lever to the string , this closes the supply-valve or damper of the stove or furnace . Of course , if this should be carried beyond the required extent the reverse action will take place . A weight in the centre of the plate , the position of which is regulated by a milled-head screw shown at the side , serves to alter the centre of gravity of the whole apparatus . The value of the motion of this weight being carefully ascertained , a scale is engraved upon it . By moving this weight , according to a scale engraved on it , the instrument may be set so as to maintain any desired temperature in the building in which it is fixed . The range of action of the instrument is from 54 ? to 66 ? Fahr. , and with a change of temperature of one degree it has the power to raise one ounce three inches . Appolds automatic Hygrometerfor keeping the Air in a Building at any desired degree of moisture . This instrument , both in principle and construction , is very similar to the automatic regulator just described . The acting portion consists also of a tube with a bulb at each end . This tube contains mercury to about half the height of each bulb , and a portion of ether floating on the mercury at each end . One half of the tube and one bulb is covered with bibulous paper , which is always kept wet , and the tube is suspended and turns freely on knife-edges placed just above the covered bulb . The action of the apparatus is as follows : A deficiency of moisture in the air increases the evaporation from the bibulous paper . This evaporation produces cold , which condenses the vapour of the ether in the covered bulb , and the mercury being pressed on by the vapour of the ether in the naked bulb is forced into the covered bulb . The uncovered bulb , being now much the lightest , rises , and raises a lever , which in its turn opens a valve at the end of a small tube . This tube communicates with a cistern kept full of water . The water which is thus admitted is suffered to trickle over heated pipes which are covered 1866 . ] 145 with bibulous paper ; upon the desired dew-point being attained , the action ceases . The range of the instrument is regulated by means of a spiral spring at one end of the tube , and an adjustable weight at the other . By means of a pencil attached to one of the levers , the instrument may be made self-registering . An ordinary Mason 's hygrometer is attached to the instrument for regulation and comparison . With a variation of one degree in the moisture of the atmosphere , the instrument is capable of supplying ten quarts of water per hour to the surface of the pipes from which it evaporated .

112606

3701662

On the Spectrum of a New Star in Corona Borealis

146

149

Proceedings of the Royal Society of London

William Huggins|W. A. Miller

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0036

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112606

10.1098/rspl.1866.0036

http://www.jstor.org/stable/112606

Atomic Physics

Astronomy

Atomic Physics

III . " On the Spectrum of a New Star in Corona Borealis " - . By WILLIAM HUGGINS , F.R.S. , and W. A. MILLER , M.D. , Treas . R.S. Received May 17 , 1866 . Yesterday , May the 16th , one of us received a note from Mr. John Birmingham of Tuam , stating that he had observed on the night of May 12 a new star in the constellation of Corona Borealis . he describes the star as " very brilliant , of about the 2nd magnitude . " Also Mr. Baxendell of Manchester wrote to one of us giving the observations which follow of the new star , as seen by him on the night of the 15th instant . " A new star has suddenly burst forth in Corona . It is somewhat less than a degree distant from e of that constellation in a south-easterly direction , and last night was fully equal in brilliancy to f3 Serpentis or v HIerculis , both stars of about the 3rd magnitude . " Last night , May 16 , we observed this remarkable object . The star appeared to us considerably below the 3rd magnitude , but brighter than e Coronae . In the telescope it was surrounded with a faint nebulous haze , extending to a considerable distance , and gradually fading away at the boundaryt . A comparative examination of neighbouring stars showed * The Astronomer Royal wrote to one of us on the 18th , " Last night we got a meridian observation of it ; on a rough reduction its elements areR . A. 1866 , May 17 ... ... ... ... ... ... ... ... 15h 53m 569s08 , N.P.D ... ... ... ... ... ... ... ... ... ... ... ... ... 63§ 41 ' 53 " , agreeing precisely with Argelander , No. 2765 of " Bonner Sternverzeichniss , " declination + 26 ? , magnitude 9'5 . " Mr. ]Baxendell writes on the 21st , " It is probable that this star will turn out to be a variable of long or irregular period , and it may be conveniently at once designated T Coronae . " Sir John Ilerschel informs one of us that on June 9 , 1842 , he saw a star of the 6th magnitude in Corona very nearly in the place of this strange star . As Sir John Herschel 's position was laid down merely by naked eye allineations , the star seen by him may have been possibly a former temporary outburst of light in this remarkable object . t On the 17th this nebulosity was suspected only ; on the 19th and 21st it was not seen . that this nebulosity really existed about the star . When the spectroscope was placed on the telescope , the light of this new star formed a spectrum unlike that of any celestial body which we have hitherto examined . The light of the star is compound , and has emanated from two different sources . Each light forms its own spectrum . In the instrument these spectra appear superposed . The principal spectrum is analogous to that of the sun , and is evidently formed by the light of an incandescent solid or liquid photosphere , which has suffered absorption by the vapours of an envelope cooler than itself . The second spectrum consists of a few bright lines , which indicate that the light by which it is formed was emitted by matter in the state of luminous gas . These spectra are represented with considerable approximative accuracy in a diagram which accompanies this paper . Spectrulim of Absorption and Spectrum of Bright Lines forming the Compound Spectrum of a New Star near e Coronae Borealis . Description of the spectrum of absorption . In the red a little more refrangible than Fraunhofer 's C are two strong dark lines . The interval between these and a line a little less refrangible than D is shaded by a number of fine lines very near each other . A less strongly marked line is seen about the place of solar D. Between D and a portion of the spectrum about the place of b of the solar spectrum , the lines of absorption are numerous , but very thin and faint . A little beyond b commences a series of close groups of strong lines ; these follow each other at small intervals , as far as the spectrum can be traced . Description of the gaseous spectrum.-A bright line , much more brilliant than the part of the continuous spectrum upon which it falls , occupies a position which several measures make to be coincident with Fraunhofer 's F t. At rather more than one-fourth of the distance which * The position of the groups of dark lines shows that the light of the photosphere , after passing through the absorbent atmosphere , is yellow . The light , however , of the green and blue bright lines makes up to some extent for the green and blue rays ( of other refrangibilities ) which have been stopped by absorption . To the eye , therefore , the star appears nearly white . However , as the star flickers , there may be noticed an occasional preponderance of yellow or blue . Mr. Baxendell , without knowing the results of prismatic analysis , describes the impression he received to be " as if the yellow of the star were seen through an overlying film of a blue tint . " t On the 17th , the lines of hydrogen , produced by taking the induction-spark through the vapour of water , were compared in the instrument simultaneously with the bright ines of the star . The brightest line coincided with the middle of the expanded line of hydrogen which corresponds to Fraunhofer 's F. On account of the faintness of the red separates F from G , a second and less brilliant line was seen . Both these lines were narrow and sharply defined . Beyond these lines , and at a distance a little more than one-third of that which separates the second bright line from the strongest bright one , a third bright line was observed . The appearance of this line suggested that it was either double or undefined at the edges . In the more refrangible part of the spectrum , probably not far from G of the solar spectrum , glimpses were obtained of a fourth and faint bright line . At the extreme end of the visible part of the less refrangible end of the spectrum , about C , appeared a line brighter than the normal relative brilliancy of this part of the spectrum . The brightness of this line , however , was not nearly so marked in proportion to that of the part of the spectrum where it occurs , as was that of the lines in the green and blue . General Conclusions.-It is difficult to imagine the present physical constitution of this remarkable object . There must be a photosphere of matter in the solid or liquid state emitting light of all refrangibilities . Surrounding this must exist also an atmosphere of cooler vapours , which give rise by absorption to the groups of dark lines . Besides this constitution , which it possesses in common with the sun and the stars , there must exist the source of the gaseous spectrum . That this is not produced by the faint nebulosity seen about the star is evident by the brightness of the lines , and the circumstance that they do not extend in the instrument beyond the boundaries of the continuous spectrum . The gaseous mass from which this light emanates must be at a much higher temperature than the photosphere of the star ; otherwise it would appear impossible to explain the great brilliancy of the lines compared with the corresponding parts of the continuous spectrum of the photosphere . The position of two of the bright lines suggests that this gas may consist chiefly of hydrogen . If , however , hydrogen be really the source of some of the bright lines , the conditions under which the gas emits the light must be different from those to which it has been submitted in terrestrial observations ; for it is well known that the line of hydrogen in the green is always fainter and more expanded than the brilliant red line which characterizes the spectrum of this gas . On the other hand , the strong absorption indicated by the end of the spectrum , when the amount of dispersion necessary for these observations wa:s employed , the exact coincidence of the line in this part of the spectrum with the red line of hydrogen , though extremely probable , was not determined with equal certainty . * The spectra of the star were observed again on the 17th , the 19th , the 21st , and the 23rd . On these evenings no important alteration had taken place . On the 17th and succeeding evenings , though the spectrum of the waning star was fainter than on the 16th , the red bright line appeared a little brighter relatively to the green and blue bright lines . On the 19th and 21st the absorption lines about b were stronger than on the 16th . From the 16th the continuous spectrum diminished in brightness more rapidly than the gaseous spectrum , so that on the 23rd , though the spectrum as a whole was faint , the bright lines were brilliant when compared with the continuous spectrum . 148 line F of the solar spectrum , and the still stronger corresponding lines in some stars , would indicate that under suitable conditions hydrogen may emit a strong luminous radiation of this refrangibility* . The character of the spectrum of this star , taken together with its sudden outburst in brilliancy and its rapid decline in brightness , suggest to us the rather bold speculation that , in consequence of some vast convulsion taking place in this object , large quantities of gas have been evolved from it , that the hydrogen present is burning by combination with some other element and furnishes the light represented by the bright lines , also that the flaming gas has heated to vivid incandescence the solid matter of the photosphere . As the hydrogen becomes exhausted , all the phenomena diminish in intensity , and the star rapidly wanes . In connexion with this star , the observations which we made upon the spectra of a Orionis and / f Pegasi , that they contain no absorption lines of hydrogen , appear to have some new interest . The spectra of these stars agree in their general characters with the absorption spectrum of the new star . The whole class of white stars are distinguished by having hydrogen lines of extraordinary force . It may also be mentioned here that we have found that the spectra of several of the more remarkable of the variable stars , namely those distinguished by an orange or ruddy tint , possess a close general accordance with those of a Orionis , 3 Pegasi , and the absorption spectrum of the remarkable object described in this paper . The purely speculative idea presents itself from these observations , that hydrogen probably plays an important part in the differences of physical constitution which apparently separate the stars into groups , and possibly also in the changes by which these differences may be brought aboutt .

112607

3701662

Condensation of Determinants, Being a New and Brief Method for Computing their Arithmetical Values

150

155

Proceedings of the Royal Society of London

C. L. Dodgson

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0037

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112607

10.1098/rspl.1866.0037

http://www.jstor.org/stable/112607

Formulae

Measurement

Mathematics

IV . " Condensation of Determinants , being a new and brief Method for computing their arithmetical values . " By the Rev. C. L. DODGSON , M.A. , Student of Christ Church , Oxford . Communicated by the Rev. BARTHOLOMEW PuICE , M.A. , F.R.S. Received May 15 , 1866 . If it be proposed to solve a set of n simultaneous linear equations , not being all homogeneous , involving n unknowns , or to test their compatibility when all are homogeneous , by the method of determinants , in these , as well as in other cases of common occurrence , it is necessary to compute the arithmetical values of one or more determinants-such , for example , as 1 , 3 , -2 2,1 , 4 3 , 5,1 Now the only method , so far as I am aware , that has been hitherto employed for such a purpose , is that of multiplying each term of the first row or column by the determinant of its complemental minor , and affecting the products with the signs + and alternately , the determinants required in the process being , in their turn , broken up in the same manner until determinants are finally arrived at sufficiently small for mental computation . This process , in the above instance , would run thus:1 , 3 , --2 2,1 , 4 =1x 14 -2x 3--2 +3X -312 3:~5 , -1 5 , -1 5 , --11 1 , 4 3 , 5 , --1 i =-21-14+42=7 . But such a process , when the block consists of 16 , 25 , or more terms , is so tedious that the old method of elimination is much to be preferred for solving simultaneous equations ; so that the new method , excepting for equations containing 2 or 3 unknowns , is practically useless . The new method of computation , which I now proceed to explain , and for which " Condensation " appears to be an appropriate name , will be found , I believe , to be far shorter and simpler than any hitherto employed . In the following remarks I shall use the word " Block " to denote any number of terms arranged in rows and columns , and " interior of a block " to denote the block which remains when the first and last rows and columns are erased . The process of " Condensation " is exhibited in the following rules , in which the given block is supposed to consist of n rows and n columns:(1 ) Arrange the given block , if necessary , so that no ciphers occur in its interior . This may be done either by transposing rows or columns , or by adding to certain rows the several terms of other rows multiplied by certain multipliers . ( 2 ) Compute the determinant of every minor consisting of four adjacent terms . These values will constitute a second block , consisting of n-rows and n-1 columns . ( 3 ) Condense this second block in the same manner , dividing each term , when found , by the corresponding term in the interior of the first block . ( 4 ) Repeat this process as often as may be necessary ( observing that in condensing any block of the series , the rth for example , the terms so found must be divided by the corresponding terms in the interior of the r--lth block ) , until the block is condensed to a single term , which will be the required value . As an instance of the foregoing rules , let us take the block -2 -1 -1 -4 -1 -2 -1 -6 -1 -1 2421 -3 -8 3 -1 2 By rule ( 2 ) this is condensed into --1 -5 8 ; this , again , by 11 -4 rule ( 3 ) , is condensed into I --26 and this , by rule ( 4 ) , into -8 , which is the required value . The simplest method of working this rule appears to be to arrange the series of blocks one under another , as here exhibited ; it will then be found very easy to pick out the divisors required in rules ( 3 ) and ( 4 ) . -2 --1 -4 -I -2 -1 -6 -1 -1 2421 -3 3 -1 2 -1 -5 811 -4 8 --2 -4 6 -8 . This process cannot be continued when ciphers occur in the interior of any one of the blocks , since infinite values would be introduced by employing them as divisors . When they occur in the given block itself , it may be rearranged as has been already mentioned ; but this cannot be done when they occur in any one of the derived blocks ; in such a case the given block must be rearranged as circumstances require , and the operation commenced anew . The best way of doing this is as follows : Suppose a cipher to occur in the hth row and kth column of one of the derived blocks ( reckoning both row and column from the nearest corner of the block ) ; find the term in the hth row and kth column of the given block ( reckoning from the corresponding corner ) , and transpose rows or columns cyclically until it is left in an outside row or column . When the necessary alterations have been made in the derived blocks , it will be found that the cipher now occurs in an outside row or column , and therefore need no longer be used as a divisor . The advantage of cyclical transposition is , that most of the terms in the new blocks will have been computed already , and need only be copied ; in no case will it be necessary to compute more than one new row or column for each block of the series . In the following instance it will be seen that in the first series of blocks a cipher occurs in the interior of the third . We therefore abandon the process at that point and begin again , rearranging the given block by transferring the top row to the bottom ; and the cipher , when it occurs , is now found in an exterior row . It will be observed that in each block of the new series , there is only one new row to be computed ; the other rows are simply copied from the work already done . 2-1 21 -3 12 -1 2121 -1 21 -1 -2 -1 1 -1 -2 -1 -1 21 -1 -2 -1 21 -1-2 112 -1 -1 21 -2 -1 -1 22 -1 21 -3 5 -5 -3 -3 -3 33 -3 -3 -3 3333 -1 333 -1 -5 -3 -1 -5 -5 -3 -l -5 3 -5 11 -30 6 -12 0060066 -6 86 -6 8 -17 8 -4 0 12 1 18 40 36 . The fact that , whenever ciphers occur in the interior of a derived block , it is necessary to recommence the operation , may be thought a great obstacle to the use of this method ; but I believe it will be found in practice that , even though this should occur several times in the course of one operation , the whole amount of labour will still be much less than that involved in the old process of computation . I now proceed to give a proof of the validity of this process , deduced from a well-known theorem in determinants ; and in doing so , I shall use the word " adjugate " in the following sense:-if there be a square block , and if a new block be formed , such that each of its terms is the determinant of the complemental minor of the corresponding term of the first block , the second block is said to be adjugate to the first , The theorem referred to is the following : " If the determinant of a block = R , the determinant of any minor of the mth degree of the adjugate block is the product of R"- ' and the coefficient which , in R , multiplies the determinant of the corresponding minor . " Let us first take a block of 9 terms , al , a , ,2 a1,3 a,1 a2,2 a2,3 = ; a3,1 a3,2 a3,3 and let ao , , represent the determinant of the complemental minor of a , , , and so on . If we " condense " this , by the method already given , we get the block { 3 , a3 , i , and , by the theorem above cited , the determinant of this , 1,3 a , 1 viz. a3 3,1 Rx a~3'1 I ~R X ~2,2 . 1 , 3 III 1 3,3 3,1 Hence PR= _l3 all I , which proves the rule . 2 , 2 Secondly , let us take a block of 16 terms : al,1. . a.1 , 4* ==R . a4,1. . a4,4 If we " condense " this , we get a block of 9 terms ; let us denote it by , If we take a block consisting of n rows and n+ 1 columns , and " condense " it , we reduce it at last to 2 terms , the first of which is the determinant of the first n columns , the other of the last n columns . Hence , if we take the n simultaneous equations , al , l xl +-al,2 x2+ *** +a , ,x , +-a , n++l=0 , al , XI ... ... ... ... ... . + al , n+1= 0 ; and if we condense the whole block of coefficients and constants , viz. al , 1 ... . al , n+1 l^ * * 0 We then condense these into the column 0 , and , supplying from 23 the second block of the first series the column , we obtain -5 3010 as the last two columns of the second block of the new series ; -5 2 and proceeding thus we ultimately obtain the two terms 12 , 12 . Observing that the y-column has the sign + placed over it , we multiply the first 12 by + y , and so form the equation 12y= 12 , which gives y= 1 . The values of z , u , and v are similarly found . It will be seen that when once the given block has been successfully condensed , and the value of the first unknown obtained , there is no further danger of the operation being interrupted by the occurrence of ciphers . +++2 +2y +zu +2v +2 =0 xy -2z uv -4 =0 2x +yz -2u v -6 =0 x -2y zu +2v +4 =0 2x y +2z +u -3v -8 =0 11 2 1-1 222426|2 511 2 4| 1 -1 -2 -1 -1 -1 -2 -1 -3 -1 -1 |.-.-2v=4 ... . v--2 2 1-1 -2-1 -6 -2 -1 -13 31 1 -2 -1--1 2426 3..3 ... . . 12 -1 2 1-3-8 30 -1 -2 -3-3-3 3 --6 1 16 61 O06 01 12 12 1 6-6 8-2.12y2 . =12 ... ... ... ... ... ... =1 -17 8-4 60 12 12 18 40 -8 136-721.36 . --72 ... ... ... ... ... ... ... ... ... .x ... ... ... ... ... x= 24 5x +2y -3z +3 =Y 3x y -2z +7 =0 2x +-3y -12 =0 52 -3 3 1-3 81 -3 12 3 -1 -2 7 -2 101 . 3=12 ... ... ... ... ... . . z4 231 -12 1-7 -14 -11 --151. . 7y= --14 ... ... ... ... ... . y2 11 5 17 | -22 22..22x=22 ... ... ... ... ... ... ... ... ... . . 1

112608

3701662

An Account of Experiments in Some of Which Electroscopic Indications of Animal Electricity Were Detected for the First Time by a New Method of Experimenting

156

167

Proceedings of the Royal Society of London

Charles Bland Radcliffe

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0038

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112608

10.1098/rspl.1866.0038

http://www.jstor.org/stable/112608

Electricity

Nervous System

Electricity

I. " An Account of Experiments in some of which Electroscopic Indications of Animal Electricity were detected for the first time by a new method of experimenting . " By CHARLES BLAND RADCLIFFE , M.D. , Fellow of the Royal College of Physicians in London , Physician to the Westminster Hospital and to the National Hospital for Paralysis and Epilepsy , &c. Communicated by CHARLES BROOKE , M.A. Received March 15 , 1866 . Very soon after the discovery of animal electricity by Galvani , I-emmer ascertained that electroscopic indications of electricity might be obtained at the surface of the human body . The instruments used in these investigations were the electroscope of Saussure and the condenser of Volta : the broad result arrived at was-that the indications in question might be sometimes present and sometimes absent ; that they pointed sometimes to positive electricity , and sometimes to negative ; and that they did not depend ( except , perhaps , in a very small degree ) upon the friction of the hair , or skin , or clothes , or carpet . Upwards of sixty years have passed since Hemmer published the account of his labours . During the first half of this period not a little good work was done in this branch of scientific inquiry , especially by Gardini in 1792 , by Ahrens in 1817 , and by Nasse in 1834 ; and what was done is in the main confirmatory of the genuineness of the work done by Hemmer . During the last thirty years , on the contrary , little or nothing has been done* . It seems , indeed , as if the discovery of the galvanometer , now a little more than thirty years ago , had diverted attention from the electroscope : at any rate it is the fact that it has been the fashion since the discovery of the galvanometer to forget the static , and to think only of the current phenomena of animal electricity . Nor is this altogether to be wondered at ; for it must be allowed that the-facilities for detecting the current phenomena of animal electricity are far , very far greater than those for detecting the static phenomena of this agent . Be this as it may , however , my own experience amounts to this-that I found it difficult to detect these latter phenomena easily and satisfactorily until I hit upon the method of investigation employed in the experiments about to be described-a method which dispenses with the use of the condenser , which appears to be as delicate as it is certain and simple , and which I now proceed to describe without any further preamble . I. An account of the method of experimenting employed in the experiments which have to be related presently . In order to carry out this method of experimenting , the instruments necessary are two small electroscopes , two insulating stands upon which to fix these electroscopes , and a conducting rod with an insulating handle . Each electroscope is provided in the usual way with a pair of gold leaves , and with slips of tinfoil in the interior of the glass bell of the instrument , and it has , in addition , an opening underneath the wooden base , by which it may be screwed on the top of the insulating stand . Each insulating stand is a piece of glass rod 9 or 10 inches in length , fixed by its lower end into a suitable foot , and having at the upper end a screw which fits into the opening underneath the wooden base of the electroscope . In one stand ( for reasons which will appear presently ) the glass stem is varnished ; in the other it is left unvarnished . The conducting rod may be of ally form . For the rest , all that need now be said is that , in order to avoid the chance of electricity being developed by the friction of lackered surfaces , the caps of the electroscopes , and the end of the conducting rod which has to be brought into contact with the caps at certain times , are left unlackered , and that , in order to secure as good insulation as possible , the exterior of the electroscopes are well varnished whenever practicable , In preparing for al experiment , the electroscopes are screwed on the insulating stands , and then charged in a particular way with free electricitythe one with free positive electricity , the other with free negative electricity . This charge is obtained by gently rubbing the glass stem of the insulating stands between the finger and thumb the positive electricity from the unvarnished glass stem , the negative from that which is varnished . The electricity thus obtained is communicated , not to the cap , which is in direct communication with the gold leaves , but through the wooden base to the tinfoil slips which run halfway up the interior of the glass bell of the electroscope ; and thus , instead of being charged directly , the gold leaves become charged inductively with the opposite kind of electricity to that which is communicated to the tinfoil slips . The result of doing this is that the gold leaves take up a given degree of divergence , and that they remain divergent so long as the tinfoil slips retain their charge of electricity . Charged in this manner , in fact , the gold leaves cannot be brought together by placing a conductor between the cap of the electroscope and the earth ; indeed , so far from this being possible , the effect of placing a conductor in this position , under these circumstances , is ( as may easily be ulderstood ) to increase the divergence of the gold leaves . s Now what has to be done in preparing for an experiment is to get the gold leaves in that second position of divergence into which they pass when the discharging rod is applied to the cap of the charged electroscope . First of all , the gold leaves are made to diverge to a given degree by charging the electroscope in the manner which has been described ; then the conducting rod is placed in position and the gold leaves are made to take up the full degree of divergence by so doing ; and when this is done the electroscopes are ready for use . The electroscopes being ' set " in this manner , the experiment which has to be performed consists in bringing the body , whose electrical condition has to be examined , to the cap of each electroscope in turn , and in noting the movements of the gold leaves . The experiment is simple , and the results are these . When the body is electrified positively , it causes increased divergence of the gold leaves in the electroscope in which these leaves are electrified with positive electricity ; and vice versed , when the body is electrified negatively , it causes increased divergence of the gold leaves in the electroscope in which these leaves are electrified with negative electricity , and diminished divergence in the electroscope in which these leaves are electrified with positive electricity . These are , as will be easily understood , the movements of the gold leaves which must take place under these circumstances . Moreover the charge of electricity in the electroscope reacts upon the body which is brought to the cap of the instrument , and produces , in a way which is intelligible enough , a certain small amount of increased divergence of the gold leaves of both electroscopes . Now this slightly increased divergence of the gold leaves in both electroscopes is of little or no moment when bodies electrified with comparatively large amounts of free electricity are made to act upon the caps of the instruments , but it is of great moment when these bodies are electrified with minute amounts of free electricity ; for in this case the movements of the gold leaves arising from the action of the free electricity will be exaggerated or masked according as they happen to be in the same direction or in the opposite direction to the movements produced by the reaction of the charge in the electroscopes . Thus , if the degree of increased divergence in the gold leaves of both electroscopes arising from the reaction of the charge in the instruments be = 2 , and if the alteration in the divergence of the gold leaves produced by the action of free electricity be of the same value , that is =2 , the result of this latter action will be , not increased divergence of the gold leaves =2 in one electroscope , and diminished divergence of these leaves =2 in the other instrument , but increased divergence =4 , in the electroscope in which it causes increased divergence ( for in this case it is the action of the free electricity plus that of the reaction of the charge in the instrument , 2+2 =4 ) , and no alteration of divergence in the electroscope in which it causes diminished divergence ( for in this case it is the converging action of the free electricity minus that of the diverging action of the charge in the instrument , that is , 2-2=0 ) , and so also in similar cases , the movement of increased divergence of the gold leaves in both electroscopes arising from the reaction of the charge in the instrument being added to or subtracted from the movement of the gold leaves produced by the action of free electricity , according as these movements happen to be in the same or in opposite directions . These , then , being the facts , it is easy to see how , by using two electroscopes , it is possible to eliminate the reaction of the charge of electricity in the instruments upon the gold leaves , and to make this reaction tell in making more obvious the action of very minute quantities of electricity . It is easy to eliminate the reaction of the charge of electricity in the electroscopes upon the divergence of the gold leaves ; for this reaction causes slightly increased divergence of these leaves in both instruments . It is easy to make the reaction of the charge of electricity in the electroscopes upon the divergence of the gold leaves tell in making more obvious the action of free electricity upon the divergence of these leaves ; for it is plain that in the electroscope in which the action of positive electricity causes increased divergence of the gold leaves , this movement will be aided by the increased divergence of these leaves arising from the reaction of the charge of electricity in the electroscopes , and , vice versed , that in the electroscope in which negative electricity causes increased divergence of the gold leaves this movement will be aided by the increased divergence of these leaves arising from the reaction of the electricity in the instrument . Nor does it follow that one of the electroscopes is in reality superfluous . A priori , indeed , it might be supposed that one electroscope would be sufficient . It might appear enough to take the movements of increased divergence of the gold leaves as evidence of the action of one kind of electricity , and the movements of diminished divergence as evidence of the other kind of electricity . But when dealing with minute quantities of electricity , it is found practically that the movements of diminished divergence are not so easily produced as those of increased divergence , and that there are impediments to free movement in this direction , arising from the clashing of the movement of diminished divergence due to the action of free electricity with the movement of increased divergence due to the reaction of the charge of electricity in the electroscope . In short , the plain truth appears to be , not only that the two electroscopes act as a check upon each other , and show the same thing from two different points of view , but that they furnish evidence which in itself is far more conclusive , when dealing with minute quantities of electricity , than can be got from either instrument singly . In the description of the experiments upon which I am now about to enter , it is necessary to be able to distinguish the two electroscopes the one from the other ; and I propose , therefore , to speak of the instrument in which the gold leaves are charged with positive electricity , and in which positive electricity causes increased divergence of these leaves , as the Positive Electroscope , and-of the instrument in which the gold leaves are charged with negative electricity , and in which negative electricity produces increased divergence of these leaves , as the Negative Electroscope . II . An account of experiments in some of which electroscopic indications of animal electricity were detected by the method of experimenting which has just been described . In this account the degree of movement of the gold leaves is indicated by arbitrary figures . It is assumed also that the increased divergence of the gold leaves in both electroscopes , which movement has been seen to arise from the reaction of the charge of electricity in the electroscope , is =2 ; and in each experiment this figure is added to the movement produced by the action of free electricity in the case where this action causes increased divergence of the gold leaves , and subtracted in the case where this action causes diminished divergence of these leaves . Thus , in the case where the movement of the gold leaves arising from the action of free electricity is =3 , the actual movement of the gold leaves in the instrument in which there is increased divergence of these leaves will be =5 , for 3+2=5 , and in the instrument in which there is diminished divergence of these leaves will be = 1 , for 3-2 =1 . Or , in the case where the movement due to free electricity is =1 , there will be a different degree of increased divergence of the gold leaves in both electroscopes ; for in the instrument in which the action of the free electricity causes increased divergence , the actual movement of the gold leaves will be =3 , for 1+2=-3 ; and in the instrument in which this action tends to cause diminished divergence , this tendency will be overpowered by the increased divergence due to the reaction of the charge of electricity in the electroscope , and the actual movement which results will be one of increased divergence =1 ; for the movement of increased divergence arising from the reaction of the charge in the electroscope , =2 , minus the movement of diminished divergence , = 1 , arising from the action of the free electricity , must be increased divergence = 1 , for 21 =1 . In the account of these experiments , also , certain abbreviations are made use of : thus i. d. stands for increased divergence of the gold leaves , d. d. for diminished divergence of those leaves . For the rest , I have only to add that these experiments , which I leave to tell their own story , with the aid only of a few short comments at the end of each series , supply the first electroscopic indications of electricity in living blood and in living nerve-tissue , and that , to say the least , they clear up all uncertainty as to the presence in the living human body and in living muscular tissue of electricity capable of supplying like indications . First Series.-Experiments which furnish electroscopic indications of electricity in the livinyg human body . In the first four of these experiments all that was done was to apply the palm of my hand or the tips of my fingers to the cap of each electroscope in turn , and to note the movements of the gold leaves produced by so doing . In the fifth experiment , the part experimented upon was brought to the caps of the electroscopes by taking hold of a loop of silk braid which had been previously attached to it . Exp. 1 . In this case the result was d. d. =4 in the negative electroscope , and i. d.=8 in the positive electroscope , -a result showing , as has been already explained , that the electroscopes were acted upon by positive electricity == 6 . Exp. 2.-Here the movements of the gold leaves indicated the action of positive electricity =2 , the facts being-no alteration of the divergence of the gold leaves in the negative electroscope , and i. d.=4 in the positive electroscope . Ex-p . 3 . In this case there was i. d.=2 in both electroscopes-a state of things showing that the hand was electrically neutral at the time , seeing that the movements of the gold leaves were only those which were due to the reaction of the charge of electricity in the electroscopes . Exp. 4.-HIere there was no alteration of the divergence of the gold leaves in the positive electroscope , and i. d.=4 in the negative electroscope-a state of things ( the reverse of what happened in Exp. 2 ) signifying that the electroscopes were being acted upon by negative electricity --2 . Exp. 5.-A part of a foot which had been removed by amputation from a patient in the Westminster Hospital twenty-four hours previously was the part experimented upon in this instance ; and the result was the same as in Exp. 3 , namely , i.d.=2 , in both electroscopes equally the result which is brought about when a body which is electrically neutral is brought to the caps of the electroscopes . *** I have performed experiments like the first four many hundred times , and I have repeatedly tested in the same way the electrical condition of other persons . In the great majority of instances the electroscopic indications were those of positive electricity . Only now and then all electroscopic indications were absent . I have also on several occasions repeated the experiment on portions of the dead body , and always without finding any signs of electricity . More than once , on the same occasion , I have found strong indications of positive electricity in one person , and very feeble indications , or no indications whatever , in another person . More than once also I have been able to detect electricity in my own body , or in the bodies of other persons at an elevation of some feet above the ground , when it was impossible to do so on the ground itself . In fact I have obtained proof of the existence of great variations in the electricity of myself and others at various times and under various circumstances , and I have begun a systematic series of observations with a view to ascertain the electrical condition of the human body at different times and under different circumstances as to health and disease . I have already in this way arrived at some curious results , and I have certainly seen enough to make me hope that a knowledge of the electrical changes in human bodies may shed much light upon the changes which are continually taking place in the vital condition of the human body , especially when the electrical changes within the body are taken in connexion with electrical and other changes without the body . Second Series.-Experiments which furnish electroscopic indications of electricity in living blood . The blood used in this series of experiments was collected in a widemouthed glass bottle capable of holding about 2 oz. Immersed in the blood and projecting to a convenient distance from the neck of the bottle , was a piece of platinum wire . The bottle was provided with a loop of silk braid , which loop was fastened in such a way as to allow the bottle to be lifted up by it without spilling the contents ; and the necessary communication with each electroscope in turn was made by taking hold of the loop and by bringing the platinum wire projecting from the mouth of the vessel into connexion with the cap of the instrument . Exp. 6 . In this case the blood used was from the internal jugular vein of a donkey , and the electroscopic indications obtained were those of negative electricity = 6 , the actual movements of the gold leaves being d. d. =4 in the positive electroscope , and i. d. =8 in the negative electroscope . Exp. 7.-Here the blood was from the internal carotid artery of the same donkey which had furnished the venous blood used in the last experiment ; and the result was also the same , namely , d. d. =4 in the positive electroscope , and i. d. =-8 in the negative electroscope , -a result denoting the action of negative electricity =6 upon the instruments . Exp. 8 . In this experiment blood from the carotid artery of a sheep was examined ; and the movements of the gold leaves were those of positive electricity = 2 , there being no alteration of the divergence of the gold leaves in the negative electroscope , and i. d. =4 in the positive electroscope . Exp. 9.-Here the blood used was from the carotid artery of a dog . The examination was made without loss of time , and the animal seemed to be in good health ; but all signs of electricity in the blood were absent , the movements of the gold leaves being those of i. d. =2 in both electroscopes equally . Exp. 10.-The blood experimented upon in this case was that which had been already used in Exp. 6 , an interval of an hour and a half having elapsed between the two experiments . In the former experiment the blood gave electroscopic indications of negative electricity = 6 ; in this instance these indications had disappeared altogether , for there was i. d. =2 in both electroscopes equally . *** I have repeated experiments like these many times upon the blood of various animals-oxen , sheep , dogs , rabbits , and so on-sometimes upon pure arterial blood , sometimes upon pure venous blood , mo:e frequently upon the mixed stream which follows the knife of the butcher in the ordinary process of slaughtering sheep and oxen . As a rule , I have found decided electroscopic indications of negative electricity indifferently in arterial , venous , or mixed blood ; not unfrequently I have failed to find any such signs . Now and then I have found comparatively feeble signs of positive electricity . In every case also where I have examined blood after an interval of an hour or so from the time when it had flowed fresh from the vessel , I failed to detect any sign of electricity , negative or positive . These experiments no doubt leave much to be discovered in the same direction , but this at least they do , they furnish the first electroscopic proof of the presence of electricity in living blood . Nay , it is perhaps not too much to say that they supply the first unequivocal proof of electricity in blood , for the current electricity recently obtained from blood by M. Scoutteten and Dr. Shettle may in reality be nothing more than the result of chemical and other changes produced by the blood upon the terminal wire of the galvanometer used in these experiments . Third Series.-Experiments which furnish electroscopic indications of electricity in living nerve-tissue . The plan adopted in this series of experiments was to the a loop of silk braid to the part to be experimented on , and to use this loop as the means for bringing this part to the cap of each electroscope in turn . Exp. 11.-The medulla oblongata of an ox obtained a few minutes after the animal had been killed in the ordinary way in the shambles , was the part used in this experiment . At one time the cut surface exposing the transverse section of the fibres and the internal grey matter was brought to the caps of the electroscopes ; at another time the uncut surface corresponding to the longitudinal surface of the fibres was treated in this manner ; and in each case the movements of the gold leaves were indicative of the action of positive electricity = 6 , or thereabouts , the only difference perceptible being a slight one of degree . The average movements obtained were those of d. d. =4 in the negative electroscope , and i. d. =8 in the positive electroscope . Exp. 12.-The brachial enlargement of the spinal cord of an ox , taken out of the canal when the carcass was being split into two lateral halves at the usual time , that is , about half an hour from the moment when the animal had been felled with the pole-axe , was used in this experiment , and the result was d. d. =4 in the negative electroscope , and i. d. =8 in the positive electroscope . It was found also that this result was the same , except in some trifling difference in degree , in the case where the transverse sectional surface of the fibres was brought to the caps of the electroscopes , and in the case where the longitudinal surface of these fibres , natural or artificial , was examined in this manner . Exp. 13.-Here the part examined was the posterior lobe of the cerebrum of a sheep which had been killed in the usual way a few minutes previously in the shambles . No time was lost in making the necessary preparations , but not the slightest indications of electricity were obtainable , the movements being only those of i. d. =-2 in both electroscopes equally . Exp. 14.-The cerebellum of a sheep was examined in this experiment , and the result was-no alteration in the divergence of the gold leaves in the negative electroscopes , and i. d. =4 in the positive electroscopes , a state of things indicating the action of positive electricity =2 upon the instruments . It was ascertained also that all parts of the cerebellum indifferently behaved in the same manner . Exp. 15 . In this experiment the brain of a donkey just killed by loss of blood was examined , and it was found that all parts of the surface indifferently , natural or artificial , gave similar indications of negative electricity == 4 , there being d. d. =2 in the positive electroscope , and i. d. =6 in the negative electroscope . Exp. 16.-The brain of the donkey used in the last experiment was used also in this instance , an interval of an hour , or thereabouts , having elapsed between the two experiments . When first examined this organ gave indications of negative electricity = 4 ; now it was found to have lost all traces of electrical activity everywhere , for the movements of the gold leaves were simply those of i. d. =2 in both electroscopes equally . ** These experiments , as I believe , bring to light a new fact , inasmuch as they furnish the first electroscopic proof of the presence of electricity in living nerve-tissue . Judging from these and several other experiments of the same kind , in which dogs and rabbits , as well as oxen , sheep , and donkeys , were put under contribution , it would seem that living nerve-tissue , as a rule , fiurnishes electroscopic signs of electricity , sometimes positive and sometimes negative in character , and that these signs are always absent when the nerve-tissue may be supposed to have lost all traces of vitality . And this also would seem to be a conclusion deducible from the same evidence-that all parts of the nerve-tissue present signs of the same kind of electricity . It would seem , in fact , as if these experiments suggested a conclusion which is at variance with a conclusion drawn by Professor Du Bois Reymond from some of his experiments . Watching the direction of the " nerve-current " which passes through the galvanometer between the longitudinal surface , natural or artificial , of the nerve-fibres , and the transverse sectional surface of these fibres , Professor Du Bois Reymond comes to the conclusion that these two surfaces are in opposite electrical conditions , the one being positive , the other negative . Because the current passes in a particular direction , he infers that these surfaces must be electrified with different kinds of electricity . But it is plain that the current might pass between parts electrified with different degrees of the same electricity ; and indeed M. Du Bois Reymond himself explains the current passing between two points of the same surface in this manner ; and therefore , even on his own showing , there is no necessity to suppose that the longitudinal surface of the nerve-fibres is electrified with one kind of electricity and the transverse sectional surface of the fibres with the other kind . At any rate , the facts revealed by the electroscope do not appear to be of doubtful significance , and the only inference which I can deduce from them is that every part of the surface of living nerve-tissue , natural or artificial , furnishes signs of the same kind of electricity , and that the only electrical differences between one part and another are nothing more than differences of degree . Fourth Series.-Experiments which furnish electroscopic indications of electricity in living muscular tissue . In this series of experiments the mode of proceeding was the same as that adopted in the last series . Exp. 17.-The piece of muscle examined in this experiment was cut out of the sterno-niastoid of an ox a few moments after the animal had been killed in the shambles , and every part of the surface was tested in turn , and , except in some trifling difference in degree , the movements of the gold leaves were in all cases indicative of the action of positive electricity = 6 , these movements being those of d. d. =4 in the negative electroscope , and those of i. d. =8 in the positive electroscope . Exp. 18.--Here the sterno-mastoid of a sheep just killed in the ordinary way in the shambles , furnished the material for experiment , and the result was-no alteration in the divergence of the gold leaves in the negative electroscope , and i. d. =4 in the positive electroscope-a result showing the action of positive electricity =2 upon the electroscopes . Exp. 19 . In this instance the portion of muscle examined was taken from the glutneus maximus of a donkey which had just been killed by hbemorrhage , and it was found that all parts of the surface indifferently supplied indications of negative electricity = 1 , the movements of the gold leaves being those of i. d. =I in the positive electroscope , and i. d. 3 in the negative electroscope . Exp. 20.-A piece of the left ventricle of the heart of a dog just dead from haemorrhage was examined in this instance , and the only movements of the gold leaves were those which are produced by the action of a body electrically neutral , namely , i. d. =2 in both electroscopes equally . Exp. 21.--Iere the piece of muscle experimented upon was that used in Exp. 17 . Twelve hours had elapsed between the two experiments , and rigor mortis had now fully set in , and the result showed that the positive electricity which was present formerly was no longer present , the movements of the gold leaves being simply those of i. d. =2 in both electroscopes equally . *** With the exception of an experiment in which Professor Matteucci incidentally states that he obtained signs de tension avec un condensateur delicat " from one of his " ( muscular piles , " these experiments furnish , so far as I know , the only electroscopic indications of the presence of electricity in living muscular tissue-perhaps the very first really distinct proofs of this fact . I have repeated these experiments several times on r the muscles , living and dead , of various animals , oxen , sheep , donkeys , dogs , and rabbits , and I have found in the great majority of instances that all parts of the surface of living muscle furnished indications of the same kind of electricity , that this electricity was sometimes positive , sometimes negative , and that these signs were invariably absent in muscle which had passed into the state of rigor mortis . These experiments , moreover , make it difficult to agree with Professor Du Bois Reymond in thinking that the longitudinal surface , natural or artificial , of the muscular fibres , and the transverse sectional surface of these fibres , are electrified with different kinds of electricity . With respect to the electricity of muscular tissue , indeed , it seems to he precisely as it is with respect to the electricity of nerve-tissue , namely this , that all parts of the surface are electrified with the same kind of electricity , positive or negative , as the case may be , the only difference between one part and another being one of degree ; and the comments upon M. Du Bois Reymond 's conclusions , when speaking upon the condition of nerve-tissue as to electricity , are equally applicable to the present case , if only the words muscular tissue and muscular current be substituted for nerve-tissue and nerve-current . In conclusion , it only remains for me to direct attention to one bearing of the facts recorded in this paper . These facts , one and all , exhibit animal electricity , not in the form of a feeble nerve-current , or of a feeble muscular current , or of the still feebler currents of less definite character , but as endowed with a considerable amount of tension . They bring to light a property of animal electricity which is more intelligible on the supposition that the primary condition of this electricity is not current but statical . It is easy to account for these phenomena of tension if the primary condition of animal electricity be statical , for tension is the characteristic property of statical electricity ; it is by no means easy to account for these phenomena of tension if the primary condition of animal electricity be that of the current revealed by the galvanometer , for the currents so revealed are far too feeble to allow one to suppose that they can be endowed with an appreciable amount of tension . In a word , with the phenomena of tension to account for which are revealed in the experiments recorded in this paper , the natural inference , as it seems to me , is that the primary condition of animal electricity is , not current , but statical , and that the currents made known by the galvanometer to which so much attention has been paid of late the muscular current , the nerve-current , and the rest-are secondary phenomena developed accidentally by placing the ends of the coil of the galvanometer so as to include points in which the electricity is different in degree . Nay , it would seem that these currents may in reality be a retarded discharge of statical electricity , for it is a fact that they cannot be detected without a coil of which the wire is so long and so fine as to be capable of giving sufficient resistance to bridle a discharge into the quieter pace of ordinary currents . Many important consequences in physiology and in pathology , as I think , result directly or indirectly from this view of the matter , of which some are set forth in some Lectures which I gave at the College of Physicians in London three years ago , and which have since appeared in print ; but it is no part of my present task to consider these consequences . Indeed , what I proposed to do in this paper I have now done ; and this was simply to direct attention to certain facts as facts , and to offer certain passing comments suggested naturally by these facts .

112609

3701662

On the Dynamical Theory of Gases. [Abstract]

167

171

Proceedings of the Royal Society of London

J. Clerk Maxwell

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112609

http://www.jstor.org/stable/112609

Fluid Dynamics

Thermodynamics

Fluid Dynamics

II . " On the Dynamical Theory of Gases . " By J. CLERK MAXWELL , F.R.S. L. & E. Received May 16 , 1866 . ( Abstract . ) Gases in this theory are supposed to consist of molecules in motion , acting on one another with forces which are insensible , except at distances which are small in comparison with the average distance of the molecules . The path of each molecule is therefore sensibly rectilinear , except when two molecules come within a certain distance of each other , in which case the direction of motion is rapidly changed , and the path becomes again sensibly rectilinear as soon as the molecules have separated beyond the distance of mutual action . Each molecule is supposed to be a small body consisting in general of parts capable of being set into various kinds of motionl relative to each other , such as rotation , oscillation , or vibration , the amount of energy existing in this form bearing a certain relation to that which exists in the form of the agitation of the molecules among each other . The mass of a molecule is different in different gases , but in the same gas all the molecules are equal . The pressure of the gas is on this theory due to the impact of the molecules . on the sides of the vessel , and the temperature of the gas depends on the velocity of the molecules . The theory as thus stated is that which has been conceived , with various degrees of clearness , by D. Bernoulli , Le Sage and Prevost , Herapath , Joule , and Kronig , and which owes its principal developments to Professor Clausius . The action of the molecules on each other has been generally assimilated to that of hard elastic bodies , and I have given some applica* It is to be supposed that certain molecules in living animal bodies are , under certain given conditions , a constant source of electricity-are so , perhaps , in the way in which certain molecules of the electrophorus are such a source . The idea is that this electricity is so supplied as to admit of a series of frequent discharges , or to keep up a constant current if these discharges are retarded sufficiently . At any rate , it does not follow that this constancy of the current of animal electricity detected by the galvanometer is an objection in itself to the idea that the primary condition of animal electricity may be , not current , but statical . 167 tion of this form of the theory to the phenomena of viscosity , diffusion , and conduction of heat in the Philosophical Magazine for 1860 . M. Clausius has since pointed out several errors in the part relating to conduction of heat , and the part relating to diffusion also contains errors . The dynamical theory of viscosity in this form has been reinvestigated by M. O. E. Meyer , whose experimental researches on the viscosity of fluids have been very extensive . In the present paper the action between the molecules is supposed to be that of bodies repelling each other at a distance , rather than of hard elastic bodies acting by impact ; and the law of force is deduced from experiments on the viscosity of gases to be that of the inverse fifth power of the distance , any other law of force being at variance with the observed fact that the viscosity is proportional to the absolute temperature . In the mathematical application of the theory , it appears that the assumption of this law of force leads to a great simplification of the results , so that the whole subject can be treated in a more general way than has hitherto been done . I have therefore begun by considering , first , the mutual action of two molecules ; next that of two systems of molecules , the motion of all the molecules in each system being originally the same . In this way I have determined the rate of variation of the mean values of the following functions of the velocity of molecules of the first system:a , the resolved part of the velocity in a given direction . 3 , the square of this resolved velocity . y , the resolved velocity multiplied by the square of the whole velocity . It is afterwards shown that the velocity of translation of the gas depends on ox , the pressure on 1 , and the conduction of heat on y. The final distribution of velocities among the molecules is then considered , and it is shown that they are distributed according to the same law as the errors are distributed among the observations in the theory of " Least Squares ; " and that if several systems of molecules act on one another , the average vis viva of each molecule is the same , whatever be the mass of the molecule . The demonstration is of a more strict kind than that which I formerly gave , and this is the more necessary , as the " Law of Equivalent Volumes , " so important in the chemistry of gases , is deduced from it . The rate of variation of the quantities a , 3 , y in an element of the gas is then considered , and the following conclusions are arrived at . ( a ) 1st . In a mixture of gases left to itself for a sufficient time under the action of gravity , the density of each gas at any point will be the same as if the other gases had not been present . 2nd . When this condition is not fulfilled , the gases will pass through each other by diffusion . When the composition of the mixed gases varies slowly from one point to another , the velocity of each gas will be so small that the effects due to inertia may be neglected . In the quiet diffusion of two gases , the volume of either gas diffused through unit of area in unit of time is equal to the rate of diminution of pressure of that gas as we pass in the direction of the normal to the plane , multiplied by a certain coefficient , called the coefficient of interdiffusion of these two gases . This coefficient must be determined experimentally for each pair of gases . It varies directly as the square of the absolute temperature , and inversely as the total pressure of the mixture . Its value for carbonic acid and air , as deduced from experiments given by Mr. Graham in his paper on the Mobility of Gases , * is D=0'0235 , the inch , the grain , and the second being units . Since , however , air is itself a mixture , this result cannot be considered as final , and we have no experiments from which the coefficient of interdiffusion of two pure gases can be found . 3rd . When two gases are separated by a thin plate containing a small hole , the rate at which the composition of the mixture varies in and near the hole will depend on the thickness of the plate and the size of the hole . As the thickness of the plate and the diameter of the hole are diminished , the rate of variation will increase , and the effect of the mutual action of the molecules of the gases in impeding each other 's motion will diminish relatively to the moving force due to the variation of pressure . In the limit , when the dimensions of the hole are indefinitely small , the velocity of either gas will be the same as if the other gas were absent . Ience the volumes diffused under equal pressures will be inversely as the square roots of the specific gravities of the gases , as was first established by Grahamt ; and the quantity of a gas which passes through a thin plug into another gas will be nearly the same as that which passes into a vacuum in the same time . ( 3 ) By considering the variation of the total energy of motion of the molecules , it is shown that , 1st . In a mixture of two gases the mean energy of translation will become the same for a molecule of either gas . From this follows the law of Equivalent Volumes , discovered by Gay-Lussac from chemical considerations ; namely , that equal volumes of two gases at equal pressures and temperatures contain equal numbers of molecules . 2nd . The law of cooling by expansion is determined . 3rd . The specific heats at constant volume and at constant pressure are determined and compared . This is done merely to determine the value of a constant in the dynamical theory for the agreement between theory and experiment with respect to the values of the two specific heats , and their ratio is a consequence of the general theory of thermodynamics , and does not depend on the mechanical theory which we adopt . 4th . In quiet diffusion the heat produced by the interpenetration of the gases is exactly neutralized by the cooling of each gas as it passes from a dense to a rare state in its progress through the mixture . 5th . By considering the variation of the difference of pressures in different directions , the coefficient of viscosity or internal friction is determined , and the equations of motion of the gas are formed . These are of the same form as those obtained by Poisson by conceiving an elastic solid the strain on which is continually relaxed at a rate proportional to the strain itself . As an illustration of this view of the theory , it is shown that any strain existing in air at rest would diminish according to the values of an exponential term the modulus of which is,10 ooo , o second , an excessively small time , so that the equations are applicable , even to the case of the most acute audible sounds , without any modification on account of the rapid change of motion . This relaxation is due to the mutual deflection of the molecules from their paths . It is then shown that if the displacements are instantaneous , so that no time is allowed for the relaxation , the gas would have an elasticity of form , or " rigidity , " whose coefficient is equal to the pressure . It is also shown that if the molecules were mere points , not having any mutual action , there would be no such relaxation , and that the equations of motion would be those of an elastic solid , in which the coefficient of cubical and linear elasticity have the same ratio as that deduced by Poisson from the theory of molecules at rest acting by central forces on one another . This coincidence of the results of two theories so opposite in their assumptions is remarkable . 6th . The coefficient of viscosity of a mixture of two gases is then deduced from the viscosity of the pure gases , and the coefficient of interdiffusion of the two gases . The latter quantity has not as yet been ascertained for any pair of pure gases , but it is shown that sufficiently probable values may be assumed , which being inserted in the formula agree very well with some of the most remairkable of Mr. Graham 's experiments on the Transpiration of Mixed Gases* . The remarkable experimental result that the viscosity is independent of the pressure and proportional to the absolute temperature is a necessary consequence of the theory . ( y ) The rate of conduction of heat is next determined , and it is shown 1st . That the final state of a quantity of gas in a vessel will be such that the temperature will increase according to a certain law from the bottom to the top . The atmosphere , as we know , is colder above . This state would be produced by winds alone , and is no doubt greatly increased by the effects of radiation . A perfectly calm and sunless atmosphere would be coldest below . 2nd . The conductivity of a gas for heat is then deduced from its viscosity , and found to be 51 po M3 y-po0 S ' where y is the ratio of the two specific heats , p0 the pressure , and po the density of the standard gas at absolute temperature 0o . S the specific gravity of the gas in question , and p its viscosity . The conductivity is , like the viscosity , independent of the pressure and proportional to the absolute temperature . Its value for air is about 3500 times less than that of wrought iron , as determined by Principal Forbes . Specific gravity is *0069 . For oxygen , nitrogen , and carbonic oxide , the theory gives the conductivity equal to that of air . I-ydrogen according to the theory should have a conductivity seven times that of air , and carbonic acid about i of air .

112610

3701662

On the Means of Increasing the Quantity of Electricity Given by Induction-Machines

171

182

Proceedings of the Royal Society of London

T. Romney Robinson

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0040

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112610

10.1098/rspl.1866.0040

http://www.jstor.org/stable/112610

Electricity

Tables

Electricity

III . " On the means of increasing the Quantity of Electricity given by Induction-Machines . " By the Rev. T. ROMiNEY ROBINSON , D.D. Received May 10 , 1866 . Among the remarkable results obtained by studying the spectra of electric discharges , is the change exhibited by certain substances when the nature of the discharge is varied . In general the mere spark shows fewer and fainter lines than when a Leyden jar is in connexion , though the amount of electricity supplied by the machine is the same . In the latter case , however , the discharge passes almost instantaneously , and therefore its concentrated action will be more powerful . But , as far as I know , much has not been attempted towards increasing the power of the jar : this cannot be done by increasing its surface ( unless indeed that be too small to condense all the electricity supplied ) ; the supply itself must be increased . This may be done in three ways : First , the power of the exciting battery may be increased . This , however , is limited by the risk of destroying the acting surfaces of the rheotome ; and by the decreasing rate at which the magnetism of the iron core increases with the primary current . In some investigations on the electromagnet ( Trans. Irish Academy , vol. xxiii . p. 529 ) I have shown that its lifting power L is approximately given by the equation A , B+ ' in which 'I* is the product of the current and number of spires , A the maximum lift of the magnet , and B the T which would excite it to half A. The rate of change is therefore inversely as ( B+t'i)2 . The results obtained with two of the magnets which I used will illustrate this . Their A 's are 781 lbs. and 278 . The first 1000 of ' make their lifts 576 and 235 ; the second 1000 adds to these 87 and 19 ; the third 35 and 8 ; and the fourth only 19 and 3 . With a primary of 180 spires , T=4000 implies a current which can evolve in a voltameter 34'7 cubic inches of gases per minute , and of course has great de'flagrating power . There is therefore not much to be gained in this direction . Secondly , the secondary helix may be made of longer or thicker wire . It will be shown immediately that the length does not increase the quantity of the current at all , and that the effect of the thickness is limited . Thirdly , the analogy of the voltaic battery suggests the plan of combining several helices collaterally , as is done when cells are arranged for quantity ; and this I think may avail to a very great extent . In spectral work , as in most other applications of the inductorium ( as the Germans have named it ) , the breaking current alone is of importance : the other , though equal in quantity , is so much inferior in tension that it is stopped by a thin film of highly rarefied air* . This current proceeds from two causes . When the circuit is broken , the current in the primary ceases ; not instantaneouslyt , but in a time which is very small ; according to Edlund less than -L ? of a second . During its decline it induces a current in the secondary . But while it was passing it had magnetized the iron core of the apparatus : this magnetism now passes away , and in doing so it also induces a current in the secondary , which lasts longer and is more powerful than the other . I compared the two by measuring those given when the core was removed from a primary , and when it was in its place : they were as 1 : 862 when the rheotome made 17 discharges in a second ; so that in round numbers the electric induction was only a tenth of the whole effect . I shall therefore in what follows confine myself to the magnetic induction . If y be the magnetism at any time t , M its maximum , P the potential of the magnet on the secondary helix , I the potential of that helix on itself , r the resistance of the secondary circuit , q the secondary current at the time t , we have , as is well known , P die _ do q= . x d ... ... . . ( a ) r dt rdt the last term being the counter current produced by the reaction of q on the helix . If the inductive coefficient of electric action be different from that of magnetic , II should be multiplied by a factor e , which in ( b ) will multiply I in the exponent and denominator . I see no reason why they should differ unless some work be lost by molecular changes in the core when excited . The great difference between the two currents which I have just mentioned arises most probably from the different values of t in the exponentials . To integrate ( a ) we must assume some relation between die and dt . The most probable is that the loss of magnetism is as the magnetism , which gives dy= -dt , whence y= Me- " . Putting b = , and supposing q to vanish with t , PMX { ( } ... . *)r)ir The total current in the time t=-= dt s--dy-Id , and hence putting F for -P ( M-y ) and c for ~i , we obtain rm The expression for the current due to the electric induction will be similar to this , so far as having the factor F and the exponential . If , as is not unlikely , the relation of dE to dt be the same as for the magnetism , they would only differ in the values of p and c. The quantity F is the current which would be produced were it not for the inductive reaction of the current on itself . It is as P directly and r inversely . The first of these , P , is as n the number of spires in the helix* multiplied by a rather complex function of its length and diameter , which is constant when they are given . The second , r , may be assumed proportional to the length and section of the wire of the helix , for in general the other resistances of the circuit are comparatively small . Hence it follows that If two equipotential helices equally excited be placed in series , the tension will be doubled ; but the current will be intermediate between that of each , for F= 2P , and if r=rw it will not be changed . If they be used collaterally ( their homonymous terminals connected ) , P remains unchanged , and therefore the currents of the helices are simply added. . If there be an external resistance , allowance must be made for it . This may be extended to any number of helices ; for calling the external resistance p , we find P Pt PP + ... . F , T 1 o+ n +. . s ... a ( .d 1 Pr ? t..9.+ r , j The constant c must be a small fraction , for in any ordinary work of the inductorium the residual ' magnetism of the core is very feeble . As i t=e-~t , pt must be large ; and as t for wire cores does not exceed a few hundredths of a secondt , , must be very large . Rev. T. 1I . Robinson on increasing the The potential II is as n2 multiplied by another function of the length and diameters of the helix ( see Maxwell 's valuable paper " On the Electromagnetic Field , " Phil. Trans. 1865 ) ; and the term b is always less than unity . When helices are consecutive their rI 's are added , not when collateral . From this it follows that --c may be neglected ; that -1is nearly unity ; and that the difference between F and ( D increases as 6 diminishes . When equal helices are consecutive , 6 as well as F are unchanged ; therefore so is 4 . When they are collateral , each separate b remains unchanged ( unless they be so close that they react on each other ) ; and therefore , as with F , the resultant ? is the sum of its components . If the resistance of the wire be diminished by increasing its section without making much change in the dimensions of the helix , b is diminished , and therefore the coefficient of F. It is evident from the form of equation ( c ) that ? has a maximum for r , and that beyond this there is actual loss of power in increasing the thickness of the wire . It remained to test these views by experiment , but the task has some difficulties . A single discharge of inductive electricity is usually determined by the swing which it causes in a galvanometer needle ; but it is scarcely possible to get two discharges exactly equal . The slightest variation in the manner of breaking the circuit , the least oxidation or roughening of the surfaces where the break is made , change the result ; and therefore it seemed best to take the actual working of the inductorium , in hopes that the average of some thousand discharges must be near the real value of the current . The rheometer which I used is Weber 's ( for the use of which I am indebted to the kindness of Mr. Gassiot ) , and it showed an amount of fluctuation even greater than I expected . With every precaution as to the action of the rheotome , the mirror of the Weber never becomes stationary , and the oscillations are irregular ; twelve of them were taken for each set , of course read at each end and reduced by the usual formula ; yet the sets differ so much , that I only offer their results as tolerable approximations . Two facts illustrating this uncertainty may be mentioned . With a mechanical rheotome driven at a uniform speed , and its acting surfaces platinum , the ratios of the current wereWhen set so that the point rises but little from the anvil. . 1'0000 Rise greater ... ... ... ... ... ... ... ... ... ... ... . . ] 7894 Rise still greater , tension of spring greater ... ... . . 19685 Rise still greater , tension further increased . 1'8371 Here a slight change of the adjustment nearly doubles the action of the inductoriulm . Another cause of uncertainty is the variable speed of the rheotome . In general it is worked by the primary current , and therefore is affected by fluctuation of the battery and the extra current of the primary . The me chanical rheotome which I have mentioned is driven by clockwork , and its speed can be exactly regulated . With it I obtained 1 . Time of rheotome 's stroke =0'2865 . Current =-1'0000 2 . , , , 0-2020 . , , 0-9298 3 . , , , , 01862 . , , 08741 4 . , , , 0-1381 . , , 07235 5 . , , , 0-1219 . , , 0-5771 6 . , , , 0-1201 . , , 05588 7 . , , , , 00983 . , , 03788 8 . , , , , 00883 . , , 02823 9 . , , , , 00671 . , , 02478 10 . , , , , 0-0476 . , , 02007 11 . , , , , 0-0278 . , , 01946 12 . , , , , 00196 . , 0-1273 13 . , , , , 00098 . , , 00470 No. 10 was taken with a mercurial rheotome ; and the remaining three with a spring one , such as Mr. Lad applies to his inductoria* . This decrease of power is due to the core requiring time to be mag . netized . Suppose the current =A+ Bt A being that caused by the electric induction , B by the magnetic , I get from the above by minimum B squares A=0'0802 ; B-=4'1713 ; =508 ; which values represent the observations pretty fairly , the probable error being + 0'049 1 . Three cells were used here : on another trial with five I had -= 129 , confirming a previous remark that the electric induction increases faster than the magnetic . Hence much power is lost by working at too high a speed . The inductorium which I use consists of a strong oak table , on which are fixed vertically four primary helices , their axes being 12 and 18 inches apart ; at which distance the mutual action of the secondary helices is scarcely sensible in the Weber . I denote these primaries by P ' , Pt ' , &c. Their wire is No. 12 ; Pt and Pt ! are 12-5 inches long ; they have , in four layers , the first 383 spires , the second 343t . Their cores of iron wire , No. 18 , are 1'12 diameter . PlT and Piv are 13-5 inches long ; they have each 181 spires in two layers , and their cores are 1'60 diameter . They are all insulated by strong glass jars , and their connectors are so arranged that the current can be sent through any one separately , or through all at once . The normal arrangement is that the battery-current passes through P1p , then through Pf and P'T collateral , and lastly through P'v . Thus the 4t or exciting power of each primary is nearly the same . On a shelf below stands a Fizeau 's condenser , each of whose coatings is 120 feet divided into k For the first nine of these the time was given by the clockwork of the rheotome ; for the rest by dropping sparks on a slip of prepared paper , which was made to travel at the rate of 12 inches per second . t The difference arose from the cotton lapping being thicker in P " . five sections . This , though so potent in respect of sparks , does not affect the quantity , which with it I found as 1'0000 , without it 0-9948 , a difference not worth noting . The case , however , would be different if there were a gaseous interval in the circuit * . Beside this shelf is a bracket which supports rheotomes of various kinds . Over the jars can be put any of the secondary helices , the constants of which are given in the following Table : The potential P and resistance of the first one , which I take as a standard , are assumed = 1 . TABLE I. Feet of Diameter Entire ghtPotential . lsistance . wire . of wire . ayer . Spire . diameter . HeighResistance . in . in . in . G ... ... . . 17,070 0-0092 73 I3,655 6'84 40 00000ooooo 0000oooo H ... ... . 17,070 0-0092 73 I3,655 6-84 40 0000ooooo 085270 I ... ... ... 8 , 0'I53 55 6,570 6'72 4'0 0'481I4 ooo0079 K ... ... ... 8,0 o'oI53 55 6,570 6'72 4'0 0'48I14 100oo79 M ... ... . 8,130 0o'o92 29 6,524 6'2I 6'o 0'47520 0'08073 N ... ... . . 8 , I30 ' ooi92 29 6,524 6*56 5'9 0'47520 o'08z82 A ... 7,000 0-0107 ... 6 , i89 5'93 3'5 044673.8o B ... . , ... . 9,200 o'o107 ... 8,135 5'93 4-0 0o60272 J50 The first six were made by Mr. Lad , who also determined for me the length and number of layers . The thickness of the wires was measured by me with a fiihlhebel which read to 0'0001 : each is a mean of ten measures at different places , for no wire that I have ever tried is quite uniform . The two last are experimental , their wire not being lapped , but merely insulated by a varnish of wax and rosin , as proposed by the late Dr. Callan : this plan does well for quantity , but cannot be trusted for any high tension . The potentials were computed , supposing the helices at the middle of tke primary Pht ( where they are a maximum ) . For GI computed them in four other positions , and had the curiosity also to measure the currents . Distance of G from centre =0 , potential 1'0000 , current 1 0000 , , , , 1 , , , 0'9842 , , , 0'9856 2 , , , 0'9790 , , , 0-9746 , , , , 3 , , , 0'9488 , , , 09488 , , , , 4 , , , 0-8798 , , 0'9181 All but the last agree tolerably . For positions of M and N , which were not central , they were specially computed . The resistances were obtained by including in the circuit of a small Grove 's cell and a tangent rheometer of 950 spires , first the helix G , then that to be determined , and lastly the sum of it and G. Assuming G= 1 , we have three equations to determine the r of the helix in question , the remaining r of the circuit , and the electromotive force of the cell . In deducing the currents , the term involving sin20 was used with a coefficient obtained by integrating through the length and breadth of the rheometer 's coil ; and as its mean diameter is 6*4 times the length of its needle , and 0 never passed 54 ? , I think the numbers of the Table are true to the last decimal . For brevity I symbolize the combinations , when in series , as a sum , G+ I ; when collateral , as a product G. H ; and for a reason which will soon appear , when two are on the same primary I denote them by a new letter , as V=G+I . At first I used I and G on Pt ; K and H on p"v . To prevent disruptive discharge , they were kept 1*5 inch asunder by disks of baked wood . The results are given in TABLE II . Sum of Name . < . FB.'* Spark . Sets . c ntb . F components . in . G ... , ... ... . . oooo 00oooo 3'95 ... I00000 oo ... ... 'o 00779 ... ... ... . . I'000ooo 3'37 ... . . I00000o 0'985385 G+H ... ... 1I0348 I-0096+. . 3 102497 ... 2'00000 0-92306 G.H. . , ... -9988 2'0223 ... 4 98837 2-0855 I'0oo I ... ... ... ... 2-5343 4'3635 1'3 I 0'59x67 . 'z23149 0'46542 I+K ... ... 27654 4'5358 2V49 3 o'60969 0 ... . o-46298 0'44872 ( LI-K). . 3'552 6'5756 o'8o 4 0'46462 46220 V+V ' ... ... 0'9996 1'3776 9'35 3 0'72562 ... ... 2z46298 o083075 V.V ' ... ... '9434 2'7319 4'39 I 0'71138 F is computed with a correction for the place of the helix on the primary , and with a resistance which includes that of the Weber =0'00779 . The Weber must have a considerable n of its own ; but as I did not know its constants , and as this r must vary with the deflection , I did not compute it . Possibly some of the discrepancies may be owing to this . The sparks show the difference of tension ; they were taken with platinum points , and when the machine was excited by four Groves . The column , sum of components , gives for the collateral combinations the values which arise from adding the 4F of each helix , taking into account the Weber 's resistance . 1 . It will be observed that G+H with twice as many spires , and V+ Vt with thrice as many as G , give the same current ; so also that of I+ K is near that of I. 2 . On the other hand , G. IH is twice G , and V. V ' twice V+Vt . 3 . It is also manifest that the effect of I is not proportional to its diminished resistance : its F is 4'4 times greater than that of G , but its actual current is only 2'5 . This is at once explained by its b being so much less . So also the ratio of the theoretic to the effective current is nearly unity in G+I , while it is only 0'73 in V+Vt , and for the same reason . In G. H. ( I+K ) the ratio is still smaller ; but I shall recur to this . I now used the four primaries I+ K-L on Pv , single helices on the others . I had some doubt whether the difference of the cores might not influence the results , and tried this with P ' , P't , and one Pv , whose core =1'90 inch in diameter and 15'5 inches long . It has 349 spires of No. 15 in two layers . G was put on each of them , and currents transmitted , which made their ' 's nearly equal . TABLE III . Name . Sect. Sets . Spark . 'F . core as P/ ... ... ... ... r'oo r 0414 3'5 2z225 1169 iv ... ... ... ... 204 'o0000 2 3'237 ii68 pv ... ... ... ... . 300 10054 2 ' 2'662 1156 It follows from this that the least of these cores is large enough for the excitation produced by four cells : the size does seem to increase the spark , though this increase may be owing to better insulation of the core-wires in P"t and Pvt . The following results were obtained with the mechanical rheotome worked at a uniform speed of 13 discharges per second . TABLE IV . 4 . F. Sets . m of . b. components . 0 00 ... ... 00 ... ... . . 0oooo 00oooo. . ooooo ... ... I'ooooo ' 00779 L=I--K ... I'8832 4'5o06 19 0'4I752 ... ... 0'6+ 034624G+L ... ... ... I'3149 I'643 2 '-81451 ... . . 16+ 0'75002G . L ... ... ... 3 '0402 5'3I09 II o'57I59 2'8324 H ... ... ... ... . 4196 I3578 2 I104551 ... ... 'o00000 0'85385 C=A+B ... 1-9882 2'01o2 2 0'99855 ... ... 0'56286+ 0'92704 N ... ... ... ... ... 2-5535 5'4o00 I 0'47202 ... ... o'3 646 0'27756 I ... ... ... ... ... 25580 4'3635 2 0'58623 ... ... 2349 0'46542 K ... ... ... ... ... 26465 4'3635 5 o6o65i. . o0'23I49 o'46542 G.K ... ... ... . 3-5558 5'2464 I 0'67776 3'8594 - . I. l T ... ... 4'3I79 6'5756 3 o065666 4'1799 G.L.C ... ... . 5'460 6'9400 3 o'74I53 4'6932 G.L.C.II ... 6'0758 8'zo8i 3 0'74030 6'0488 M I+N ... ... ... 252o7 5'4586 2 0-46179 0 ... . . o'63292 0'26862 =0 ... ... ... ... I76I6 5'4586 4 0'32271 ... ... 0'73130 0'23248 S=M+N ... I'6687 4'9644 I 0o33614 ... . . 0o658Io 0'28543 L. 0 ... ... . . 3'4596 9'5774 I 0'36124 3'4996 MNI K ... 8-'939 15'7398 0'52058 8'2736 * 2'5 sets taken on the first cday were very unsteady . The one taken on the second was close , and gave 1'0267 . t At the same time I tried two helices similar to A and B , except that their wire is varnished iron , which were given to me by Dr. Callan . Their ~4 is 0-6887 , and their spark only 0'524 in . The 4 of AB is 2-9138 times as great , a difference caused solely by the greater resistance of the iron . 1 . As before , two helices in series give no increase of quantity ; M+ N is the same as N , G+L nearly the mean of G and L. 2 . The quantity of collateral helices is seen in column 6 ( as in Table II . ) to be the sum of the separate actions of each . The discrepancies are not greater than what can be explained by the uncertainties inherent in these measures , which I have already described . One apparent exception is a strong confirmation of this.rule the case of G. H ( 1 + K ) . Its observed ( I=3'0552 , while the sum =4'6220 . G and I being on the same primary are excited together ; but in measuring either , as there is no current in the other ( but merely a state of tension ) , their n is not changed . When , however , they are connected collaterally , the currents react on each other , their [ I 's are increased : the V 's are thus diminished , and therefore their resultant is the sum of quantities less than those used in the computation . The b 's in this case become-for G 0'94289 , for H 0-79885 , and for I+ K 0'34588 , which are quite sufficient to account for the difference . 3 . As with I in Table II . , so here it will be observed that N has less relative power than either I or K ; its actual power is even less , though its theoretical force exceeds theirs in the proportion of 5 : 4 . This is explained by its b being so much smaller ; but it gives this important information , that , at least in helices of these dimensions , nothing is gained by using wire thicker than that of I , or of an inch* . 4 . The effect of L is far less than that of I+ K. In the first the helices are on the same primary , in the other on separate ones . In the former case the II is larger , for it is the sum of the [ 1 of each on itself , and those of each on the other ; b therefore is less . Besides , the potential of the core on the helices is less than when each of them is central on it . The difference is even more remarkable in O as compared to its elements M+N , its effect being only 0'7 of the other , and 0-3 of the theoretic power . The same disparity of course prevails in their combinations ; O. L giving only 3'46 , while the same four helices arranged on separate primaries give 8 ' 19 . The combinations G. H ( I+ K ) and G. L. H have the same helices ; but in the first two were on the same primaries . As , however , they were 1*5 inch instead of 0'5 apart , the [ I was not so much increased as in the other cases , and therefore there is not quite so great a decrease of power . The following practical maxims may be deduced from the experiments and reasoning whiph I have related . The attention of instrument-makers has been chiefly directed towards increasing the length of spark given by these machines , and in this they have succeeded to a surprising degree ; but in doing so they have not added to the quantity of electricity which is produced by them . This , however , is by far the most important object ; for in most applications of the inductorium all tension above what is necessary to force the necessary quantity of current through the circuit is useless , nay sometimes injurious* . I am inclined to think that a tension which gives sparks of 4 inches will be found quite sufficient in ordinary cases , and this will be given by about 20,000 spires ; all beyond only adding to the weight of the instrument , its cost , and the difficulty of insuring its insulation , It must be kept in mind that the mere quantity is independent of the length of wire : I actually found it the same for a flat spiral of 21 spires and for a helix of 13,655 . It is not , I believe , ascertained what is the best proportion of height and diameter for a secondary helix of a given number of spires . It is generally made as long as its primary , though perhaps not on any definite principle . The magnetic potential P is in this form a little greater than in that which I used , but so also is II : the length of wire is less , which increases F , but also decreases b ; and a priori it is not easy to decide which way the balance inclines . The I is something less if the spires be in separate sections than if they be in one continuous coil . The dimensions of the core do not seem to be of importance as to quantity within the limits which I tried ; their length seems to increase the tension . The quantity is greatly diminished when the rheotome works rapidly ; and in spectral work the probable limit of its slowness is that the impression on the eye shall be continuous . The quantity increases with the diameter of the wire up to a maximum , which is attained when this is about the sixty-fifth of an inch . Helices may be combined either for tension or quantity without much loss of these respective powerst . If for the first , they are combined in series ; the general tension is the sum of the individual ones , and in this way we can obtain sparks of a length limited only by the strength of the insulator which is interposed between the primary and secondary helices . If the latter be all of the same wire , the quantity remains unchanged ; if they differ in this respect , it will be intermediate between the weakest and strongest . If they are combined for quantity , they must be set collaterally , i. e. all their positive terminals connected , and all their negative . The resulting current will be the sum of all the separate ones , but the tension is not increased ; the sparks seem even a few hundredths of an inch shorter , but are much denser , and in the higher combinations approach to the character of a jar discharge . Hence there is no risk to the apparatus by extending this mode of combination to any extent . It deserves notice that the helices need not be equal in tension or resistance ; thus the arrangement G. K gives little less than the sum of its : components , though K has only half as many spires as G and but a tenth of its resistance . In combining these instruments , the primaries should not be consecutive if of large numbers , for so the action of their extra-current would be very destructive to the rheotome ; with P'+P"t containing 726 spires in series the spark in the mercurial one is almost explosive , but when they are collateral it works quietly . Were , however , ten or twelve to be so combined , it would require a battery of very large cells to maintain the current , and it is better to have a separate battery for each pair of primaries . In this I find no difficulty ; the negative* poles of all the batteries are connected with the mercury of the rheotome ; from its platinum point , separate wires go to the entering bind-screw of each primary , other wires go from their exit bind-screws to the positive poles of their respective batteries , and thus their action is perfectly simultaneous . Of course , if many batteries were used , the current in the rheotome might be too powerful , but then there would be no difficulty in having separate rheotomes worked by one electromagnet , and ( at least with the mercurial form ) adjusting them by a revolving mirror to perfect synchronism . In this way I feel sure that we can attain an amount of electric power which has not yet been approached by the inductorium , and which may be expected to be a most powerful means of research in those inquiries to which I referred at the commencement of this paper . At the head of these stands the palmary discovery of Mr. Huggins , that there are nebulae and comets whose matter possesses spectral attributes not corresponding to that of the sun , the stars , or our own earthly elements . Is that difference an indication of some body sui generis , or a mere result of peculiar temperature or other molecular conditions ? Is , for instance , the bright line , corresponding to one of nitrogen , which occurs , we may say , normally , produced by nitrogen as such ? If so , what has blotted out the other bright lines of that magnificent spectrum ? Is it due to an element of nitrogen , dissociated by some enormous temperature from other elements , perhaps from hydrogen , one line of which is also present ? And the third line , elsewhere unknown-is it the herald of a new body , or merely a derip vative from another spectrum ? We cannot even hope for an answer to these questions till the spectra of at least those elements which seem cosmical have been examined through a range of temperature extending from the lowest that developes in them luminous lines , to the highest that is excited by the most potent electric discharges which we can produce and control . Now , to obtain such a graduated range , the plan of combination which I have been describing seems well fitted . It , of course , cannot be expected to equal , under any extension , the wonderful voltaic battery of Mr. Gassiot ( at least its arc-discharge ) ; but how few can avail themselves X If the mercury be made positive , each discharge makes a sharp report and blows about the metal and alcohol in most unpleasant profusion . of such an instrument as that ! But if , as seems probable , we can without much difficulty increase the heating-power of the induction-discharge an hundredfold , we shall have made a very great step , and by means which are everywhere accessible . Inductoria are common ; there are few situations where a physicist cannot obtain access to several , and combine them as Despretz did the voltaic batteries of Paris to make the experiments which have thrown such splendour on his name .

112611

3701662

On the Stability of Domes

182

188

Proceedings of the Royal Society of London

E. Wyndham Tarn

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0041

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112611

10.1098/rspl.1866.0041

http://www.jstor.org/stable/112611

Measurement

Formulae

Measurement

IV . " On the Stability of Domes . " By E. WYND)HAM TARN , M.A. Communicated by GEORGE GODWIN , Esq. Received May 5 , 1866 . The few writers who have attempted to treat the subject of the Equilibrium of Domes mathematically , have entirely failed to obtain results that are of any practical use to the architect . Their failure has arisen from taking a too theoretical view of the subject , and endeavouring by mathematical reasoning to find the form which a dome ought to have in order that it might stand safely . Such a question is of no practical utility , as domes of various sizes and forms have been erected for centuries past , and the question for the architect is , -given a dome of certain form and size , what are the conditions which must obtain between it and the wall of the building it is intended to cover , in order that the whole structure may be in a condition of stability ? The object , therefore , of this paper is to find a solution to the following problem : Given a spherical dome , built of stone or brick , of any radius and thickness , and standing on a " drum " or walls of any height ; to find the thrust of the dome on the " drum , " and the thickness that must be given to the walls in order to insure the stability of the structure . I take the case of the dome having a spherical section , as being the form most commonly used ; but the same method of investigation will apply to domes of any form . In this investigation I shall consider the dome as made up of a large number of arched ribs , of which the bases resting on the top of the " drum " subtend a small angle ( 9 ) at the centre , and the vertices have no thickness ; each rib having the form of a wedge cut out of the spherical shell by two planes intersecting in a vertical line through the centre , and making the small angle 0 with each other . I shall then consider that the two wedges thus formed on opposite sides of the dome , thrust against each other at the vertex , as in the case of an ordinary semicircular arch , and by this means keep each other in equilibrium . Of course no arch of this form if built alone could stand for a moment , as it would give way laterally ; but in the dome this is prevented by the parts on each side of the rib under consideration . This method is adopted by Venturoli in treating on the equilibrium of domes . Fig. 1 represents a rib of the form above described cut out of the dome , and the corresponding part of the " drum " which sustains it . The arch will have a tendency to fall in at the crown C D , and open outwards at the haunches E F , causing the joint CD to open at D , and that at OF to open at F. We may therefore suppose that N , the thrust of the corresponding rib on the opposite side , acts at C. We shall now find the effect of the force N upon a given joint OF . Let P be the weight of the portion of rib above OF ; x the perpendicular distance from E of a vertical from the centre of gravity of P ; y the vertical distance of CN from E. Then the moments of these forces about E are Px and Ny ; and in order that there may be equilibrium , we must have N equal to the greatest value of P. e. We have therefore to express Px in gY terms of 0 , the angle which FE makes with the vertical , and find what value of 0 makes Pa maximum . Let r be the internal and R the external radius of the sphere , 8 the weight of a cubic foot of the material of which it is composed . Then the volume of any portion of the rib ( p qrs CD ) is V= ! fsinO.de.dr . ; ... ... ... ( A ) so that P= . V=3 . q ( 1 -cos 0 ) R 7 , taking limits from 0=0 . 3§ 1866 . ] 183 Ifgis the centre of gravity of the portion of the rib whose weight is P , and G its projection on OA ; then if OG=z , we find the value of z from =SSSr3 . sin 0 . cos. dr . d. dp SSSr2 . sin 0 . d. dO sinl SSr3 ( 1-cos 20 ) dr. . d --3 ' g.r2..sin 0 . dr . dO( And since q is small , we may consider 1 --_ , nearly ; in which case 3 R4--r40sin 20 81 3-r 1-coso Now x is the perpendicular distance of gG from E ; therefore --=r sin 0 . R-3 3 O-I-r4 -sin 20 Therefore Px=.p ( 1 -cos 0 ) t rsin 0R4-sin 20 3X 8t_r-r l-cos0 J or PxJ 8r ( R3-r3 ) sin0 ( 1 -cos 0)-3 ( R4-r4 ) ( 0-I sin 20 ) . And since y=R-1r cos 0 , and Np - , y N. 8r ( R3-r3 ) sin 0(1-cos 0)-3 ( R4--r ' ) ( 0-sin 20 ) 24 R-r cos 0I will take q as the circular measure of an angle of 2 ? , or -7r ='0349066 , in which case we have N= 001454 Sr(R3-r3 ) sin 0 ( 1 -cos 0)-3 ( R4--4 ) ( 0-sin 20 ) R1-r cos 0 ='001454 x N ' , say . We have now to find what value of 0 will make N ' a maximum , and as the ordinary rules for maxima will not apply to this expression , we must find it by calculating N ' for different values of 0 . I have done this for the case when r2 10 , R= 11 , and find that N is greatest when 0= 70 ? ; thus 0=69 ? ... ... . -506'034 0=70 ? ... ... ... . N'=506-241 071 ... ... ... . N'=506-018 . We have now to substitute in N the values of 0 , sin 0 , &c. when the angle is 70 ? , or when 0=35 9= '22173 , sin 0=-93969 , cos 0= 34202 , sin 20 90 = '64279 . This reduces the expression for N to N=_ 007192r ( I3--r)-0039273 ( Rl-r4 ) --4 t02 We can now transpose N and P to the point E ; and in order to find the thickness of the pier , we proceed to take their moments , together with those of the part of the rib below OF , and the pier itself , about the outer bottom edge S of the pier . If we call yS= b , the perpendicular distance from S of the direction of N , then b=H+r.cos0 , ... . . ( 2 ) where I is the height RS of the pier or " drum . " Let Se=a , the distance from S of a vertical dropped from E ; F=the weight of the portion of the rib below OF ; c=the perpendicular distance from S of a vertical from the centre of gravity of the lower portion of the rib whose weight is F ; Q=the weight of the portion of the " drum " on which the rib stands , and q=the distance from S of a vertical from its centre of gravity ; we have then ( in equilibrium ) the equation N.b=P.a+Q.q+F.c , ... . . ( 3 ) which I will call the Equation for Equilibrium . From this equation we can find the thickness ( t ) of the pier necessary to produce equilibrium . In order , however , that we may have stability in the structure , we must multiply Nb by the coeffcient of stability , which we may take as 2 . The equation from which to find the value of t then becomes 2N . b=P.a+Q.q+F . c , ... ... ( 4 ) which I will call the Equation of Stability . I now proceed to find the values of P. a , Q. q , and F. c. The value of P was previously found to be P=B . 1-cosO ) R--r ; and if we substitute for q and 0 their values , P= -007656 ( R3-r3 ) . Also a=Se=t+r(l-sin 0)=t+'06031 r ; so that we find for the value of P. a , Pa= 007656 6 ( R3-3 ) t+ 0004618 a. ( R3-r3 ) ... . ( 5 ) The value of F is found by means of the integral ( A ) , taking the limits from 0=0 to 0=-- ; which gives us 3__ -r3 F=B..cos O3r ==00398 a ( R3r ) . Let z1 be the distance from O on OA of the perpendicular dropped from the centre of gravity of the portion of the rib whose weight is F. Then the integral ( B ) gives us , by taking the same limits of 0 as for F , --O+ sin201 3 R4 r4 220 18 lt3-r3 cos 02 And if we substitute for 0 its value , RI4 _r4 z=-*7351 a And c=OR-z1=-t+r-- , . Hence we find F. c= -00398 a ( R3-r3 ) t+ 00398 3 { r ( R3-r3)-7351 ( R4-r4 ) } . ( 6 ) We have now to find the moment about S of the weight of the pier . Let Q be the weight of the pier , a , the weight of a cubic foot of its material ; then Q= ? . 1 ( ( r+ t)2-r2 ) . H= ( 2r+t ) t. H =-017453 a ( 2r +-t ) t. H. Let figure 2 represent the plan of the pier , g its centre of gravity , ST=t its thickness . Then by the integral calculus we find 4 ( r+ t)-3 r3 sin ? 0 sin ? I_ O3( +)2X7 ; or putting =3 ( r $t)2 _ r2 72 _2 ( r+ t)3-r__2 ( 3'+ 3 ? t+ t2 ) . 3 ( 2.+ t)2-.2 3 ( 2r+ t ) q=Sg-=OS-Og=r+ t-Og =3 ( rt ) ( 2r+t)-2 ( 3r2+3rt+ t2 ) 3 ( 2r-+ t ) 3rt + t2 3 ( 2r+t ) We therefore obtain for the value of Qq , Qq=-017453 1(2r+ t ) t. 3r+ tt 3 ( 2r ? t ) =*0058177 . t2 ( 3r+ t ) ... H. ( 7 ) We can now , by adding together the several quantities ( 5 ) , ( 6 ) , ( 7 ) , and equating to the value of N6 as found from ( 1 ) and ( 2 ) , form the equation for equilibrium ( 3 ) , which will be a cubic equation in respect of t. We shall thence find the value of t necessary to produce equilibriumm in the structure , and , by equating the same quantities to 2Nb , form the equation for stability ( 4 ) , from which we get the value of t necessary to produce stability in the structure . The following examples will serve to show how readily these formulm can be applied , and the use which the practical architect may make of them . Example 1:Let r= 10 ft. , R=1 ft. , -= 125 lbs. , = 150 lbs. , H= 50 ft. From ( 1 ) ... N= 920092 ; , ( 2 ) ... b= 53-4202 ; therefore Nb =4915 , and 2Nb =9830 . From ( 5 ) ... P.a= 316-767 t +191-06975 ; , , ( 6 ) ... F. c= 164-6725 t-5054 ; , ( 7). . Q.q= 1308-98 t2+ 43-63275 t. Hence the equation for equilibrium ( 3 ) is 4915=43-63275 t3+ 1308-98 t2 481 4395 t+ 14052975 , which reduces to t3 + 30t2-+1 103t--109'42-0 . We can solve this by means of Horner 's process , and find t= 1-7 ft. for equilibrium . The equation for stability ( 4 ) becomes 9830=43-63275t3+ 1308-98t2+481 4395t 4140'52975 , which reduces to 430t2+1 103t-222-069=0 , from which we obtain , by Homer 's process , t=2'45 ft. for stability . Example 2:Let r=30 ft. , R=33 ft. , H=80 ft. , 6 and a , as before . From(1 ) ... N= 2483-84 ; , ( 2). . b= 90-2606 ; therefore Nb =224192-8 , and 2Nb =448385-6 . From ( 5 ) ... P. a= 8552-71 t+415476-65 ; , , ( 6 ) ... F.c= 4446-16 t+ 4094-17 ; ( 7 ) ... Q.q= 69-8124t3+ 6283-116t2 . Adding and reducing , the equation for equilibrium becomes t3 +90t2+ 186'2t-3048-31 =0 , whence t=4-83 ft. for equilibrium . And the equation for stability is t3+ 90t2 + 186-2t-6159'7=0 , whence t=7-07 ft. for stability . Example 3:I will apply the formulae to the case of the dome of Sultan Mohammed 's tomb at Beejapore , described in Mr. Fergusson 's 'Handbook of Architecture . ' One peculiarity of this structure is that the inner face of the dome is set 5 ft. 6 in . within the inner face of the wall on which it rests , as shown in fig. 3 . ; so that in calculating the values of a , &c. , we must add 5-5 ft. to the thickness t ; hence we shall get a proportionately less value for t from the resulting equations . In this dome , r=62 ft. , R=72 ft. , H=-=116 ft. ; and we will suppose , as before , that 3=125 lbs. , -=150 lbs. From ( 1 ) ... . N= 31132 ; , , ( 2). . b= 137-20524 ; therefore Nb =4271473-522 , and 2Nb =8542947-044 . From ( 5). . P. =957 ( 134920 ) ( t +55)+3-56745 ( 134920 ) =129118'44 t+1191511-78 ; ( 6). . F. c=-4975 ( 134920 ) ( t+5 5)--4975 ( 527854-4 ) =671227t + 106567-28 ; , , ( 7 ) ... Q.=10122798 3+186xl 01 22798t2 . Adding and reducing , the equation for equilibrium ( 3 ) becomes t3+ 186+t2 1938-6t-29373-24=0 , whence t=8-2 ft. for equilibrium . And the equation for stability ( 4 ) becomes t3+ 186t2+ 1938'6t-71570=0 , whence t= 14-66 ft. for stability . In the construction of this particular dome , the values obtained above for t will only apply to four points on the walls which carry the dome ; for instead of being built on a circular " drum , " this drum is made to cover a square chamber by means of " pendentives , " which are so arranged as to throw the thrust principally on the angles of the building , where the values of a and c will become very great , and it is only at the centre of each of the four sides that the above equations can be employed to compare the thrust of the dome with the strength of the walls . At these four points the walls are about 11 ft. thick , so as to be considerably more than sufficient to produce equilibrium ; and the coefficient of stability at these points is 1-374 instead of 2 . Had the dome therefore been built on a circular drum of 11 feet thickness , in all probability the edifice would not have stood for any length of time . Much of the thrust of a dome may be counteracted by means of an iron belt placed round it at the point where the thrust is greatest . This point I have shown to be at 70 ? from the crown , or 20 ? from the springing .

112612

3701662

Anniversary Meeting

188

189

Proceedings of the Royal Society of London

fla

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112612

http://www.jstor.org/stable/112612

Neurology

Optics

Neurology

I. " On the Anatomy of the Fovea centralis of the Human Retina . " By J. W. HULKE , F.R.C.S. , Assistant Surgeon to the Middlesex and Royal London Ophthalmic Hospitals . Communicated by WM . BOWMAN , Esq. Received May 26 , 1866 . ( Abstract ) . 1 . The Fovea centralis is a minute circular pit in the inner surface of the retina , made by the radial divergence of the cone-fibres from a central point , by the thinning and the outward curving of the inner retinal layers towards this point , and by the peripheral location of the outer granules belonging to the central cones . 2 . The inner surface of the retina declines in a rapid uniform curve from the edge to the centre of the fovea , and very gradually from the edge towards the ora retine ; so that the edge of the fovea is the most raised part in the macula lutea , where the retina is thickest , and the centre of the fovea the most depressed part in the macula , where the retina is thinnest . 3 . At the centre of the fovea , proceeding from the outer to the inner surface of the retina , we meet with the following structures in succession:the bacillary layer and the outer limiting membrane , a small quantity of finely areolated connective tissue , the inner granule-layer and the ganglionic layer very attenuated , a thin granular band containing optic nerve-fibres , and the membrana limitans interna . 189

112613

3701662

On the Anatomy of the Fovea Centralis of the Human Retina. [Abstract]

189

192

Proceedings of the Royal Society of London

J. W. Hulke

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112613

http://www.jstor.org/stable/112613

Neurology

Biology 3

Neurology

I. " On the Anatomy of the Fovea centralis of the Human Retina . " By J. W. HULKE , F.R.C.S. , Assistant Surgeon to the Middlesex and Royal London Ophthalmic Hospitals . Communicated by WM . BOWMAN , Esq. Received May 26 , 1866 . ( Abstract ) . 1 . The Fovea centralis is a minute circular pit in the inner surface of the retina , made by the radial divergence of the cone-fibres from a central point , by the thinning and the outward curving of the inner retinal layers towards this point , and by the peripheral location of the outer granules belonging to the central cones . 2 . The inner surface of the retina declines in a rapid uniform curve from the edge to the centre of the fovea , and very gradually from the edge towards the ora retine ; so that the edge of the fovea is the most raised part in the macula lutea , where the retina is thickest , and the centre of the fovea the most depressed part in the macula , where the retina is thinnest . 3 . At the centre of the fovea , proceeding from the outer to the inner surface of the retina , we meet with the following structures in succession:the bacillary layer and the outer limiting membrane , a small quantity of finely areolated connective tissue , the inner granule-layer and the ganglionic layer very attenuated , a thin granular band containing optic nerve-fibres , and the membrana limitans interna . 189 4 . The bacillary layer contains only cones in the fovea , but rods in addition towards the periphery of the macula lutea . 5 . The cones and rods in the macula are longer and more slender than at a distance from it . Although the greater slenderness is more apparent in the cones , yet the most slender cones are stouter than the rods . 6 . In both cones and rods an inner and an outer segment are discernible , and both segments consist of a sheathing membrane and contents . In the outer segment the contents do not exhibit any indication of structure . The inner segment , where its dimensions permit , contains an " outer granule , " and is always produced in the form of a fibre , which connects the cones and rods with the inner layers . These I have called the primitive coneand rod-fibres , collectively primitive bacillary fibres . ( K6lliker , in the last edition of his ' Handbuch der Gewebelehre , ' restricts to these the term " Miller'sfibres , " which was originally exclusively , and is still very generally given to the vertically radial connectivetissue fibres first described by H. Miuller . ) 7 . An outer granule is intercalated in each primitive bacillary fibre , 1st , where the inner bacillary segment is too slender to include the granule , and , 2nd , where the segment is associated with a distant granule . This kind of connexion always obtains with the rods , and with the cones at the centre of the fovea . The outer granules which belong to the rods are not distinguished from those which belong to the cones by any constant characters . 8 . The primitive bacillary fibres run obliquely from the outer towards the inner surface of the retina , and radially from the centre of the fovea towards the periphery of the macula lutea . 9 . They form a very conspicuous obliquely fibrillated band , lying between the outer and the inner granule-layers , in which the primitive fibres combine in bundles which have a plexiform arrangement . This band corresponds to that band which in the chameleon 's retina I called the conefibre plexus . Muiller and K6lliker call it the intergranule-layer . 10 . Between the inner surface of this layer and the inner granule-layer , there is a thin granular band of finely areolated connective tissue , through which the bacillary fibres pass into the inner granule-layer . It is in part derived from the terminal divisions of the vertically radial connective-tissue fibres , and it answers to the band which in the chameleon I termed the intergranule-layer . 11 . In the inner granule-layer two kinds of granules are distinguishable , nuclei and nucleated cells . Both are in connexion with the oblique bacillary fibres , which in this situation are exceedingly delicate , and require a high magnifying power and a good section for their demonstration . 12 . The connective-tissue fibres ( generally known as Muller 's radial fibres ) , which traverse the retina in a vertically radial direction from the membrana limitans interna towards the outer surface , are very conspicuous in the inner layers , where in sections transverse to the direction of the optic nerve-fibres they are arranged in arcades , which contain the lastnamed fibres and the ganglion-cells imbedded in a granular matrix of finely woven connective tissue . They are less visible in the outer layers , apparently because many of their terminal divisions lose themselves in the ( connective tissue ) intergranule-layer ; and hence the decussation of the oblique bacillary and the vertically radial connective-tissue fibres within the cone-fibre plexus , so conspicuous in the chameleon , is scarcely noticeable in the human retina . Deductions . 1 . Since the total of the effects of light upon living tissue will be greater as the extent of tissue traversed by it is greater , and since the relative common sensitiveness of a surface varies with the number of distinct sentient elements it contains , it follows that the greater length of the cones and rods , and their greater slenderness , which allows a larger number of them to the superficial unit , are in harmony with the greater sensitiveness of the retina at the macula lutea . Inasmuch , however , as the foveal cones are stouter than the rods , a superficial unit at the centre of the fovea contains fewer sentient ( i.e. percipient ) elements than the same unit near the periphery of the macula lutea ; and on this ground the sensitiveness of the retina at the fovea should be less than that of the retina near the periphery of the macula . On the other hand , the extreme thinness of the inner layers of the retina at the centre of the fovea , places the bacillary layer here most favourably for receiving incident light . 2 . The division of the rods and cones into an outer and an inner segment is natural . The facts in support of this are , the presence of the division in perfectly fresh specimens ; its sharpness and constant occurrence at a definite place ; the constantly rectilinear figure of the outer , and the curvilinear figure of the inner segment ; the different refractive powers of the segments ; and their different behaviour towards staining and chemical solutions . 3 . From these structural differences it is a fair inference that the segments have different physiological meanings . The higher refractive power , straight sides , and slender cylindrical or prismatic figure of the outer segment may be adaptations for confining within the segment light incident upon its ends , and for preventing the lateral escape of light through the sides of the segment into neighbouring cones and rods . These considerations incline me to adopt the opinion that this segment has an optical function , an opinion which derives further support from the fact that , in those animals in which the segment is so wide a cylinder that a ray might be incident upon the inner surface of its sides at a small enough angle not to be reflected but to pass out , the segment is insulated by a sheath of black pigment . The inner segments of the cones and rods are the specially modified peripheral terminations of the optic nerve-fibres ; and at their junction with the outer segment the conversion of light into nerve-force may take place . 4 . The outer granules being the nuclei of the inner coneand rod-segments , probably maintain the integrity of these as living tissues , and are not directly concerned in their specific functions as organs of perception . 5 . The primitive bacillary fibres are the link by which the cones and rods communn icate through the inner granules and ganglion-cells with the optic nerve-fibres . 6 . The smaller inner granules are nuclei of the oblique bacillary fibres in the inner granule-layer ; or they may be small bipolar ganglion-cells , and act specifically on the forces transmitted through the oblique fibres from the cones and rods . The larger inner granules not being distinguishable by any definite structural characters from the smaller cells of the ganglionic layer , may agree with these latter cells in function . 7 . Since the ganglion-cells ( of the ganglionic layer ) are fewer than the inner granules , and much fewer than the cones and rods , and since it is probable that these latter communicate with the optic nerve-fibres only through the ganglion-cells , it follows that one ganglion-cell probably is in correspondence with more than one inner granule and with several cones and rods . From this it is not an improbable conjecture that the cones and rods are disposed in groups , each of which is represented by one or more ganglion-cells thef unction of which is to connect or coordinate the individual action of the separate bacillary elements in their groups . in a manner analogous to that attributed to the ganglion-cells of the spinal cord by Van der Kolk* . 8 . There is a close general resemblance between the human fovea and that of the chameleon t.

112614

3701662

Second Memoir 'On Plane Stigmatics.' [Abstract]

192

203

Proceedings of the Royal Society of London

Alexander J. Ellis

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112614

http://www.jstor.org/stable/112614

Formulae

Optics

Mathematics

II . Second Memoir " On Plane Stigmatics . " By ALEXANDER J. ELLIS , F.R.S. , F.C.P.S. Received May 26 , 1866 . ( Abstract . ) Let there be two groups of points upon a plane , termed , for distinction , indices and stigmata respectively , bearing such relations to each other that any one index determines the position of n stigmata , and any one stigma determines the position of m indices . The theory of these relations between indices and stigmata constitutes plane stigmatics . Each related pair of index X and stigma Y constitutes a stigmatic point , henceforth written " the s. point ( xy ) . " The straight lines joining any index with each of its corresponding stigmata are termed ordinates . If , when I have an impression that I have seen this in a German author , but have not been able to find the passage again . t H. Miller , " IUeber das Auge des Chamaleon , " Wurzb . naturw . Zeitschr . Bd . iii . S. 36 . the index moves upon a straight line , the ordinate remains parallel to some other straight line , the relation between index and stigma is that expressed by the relation between abscissa and ordinate in the coordinate geometry of Descartes . When only one index corresponds to one stigma and conversely , and both indices and stigmata lie always on one and the same straight line , or the indices upon one and the stigmata upon another , the relations between indices and stigmata are those between homologous points in the homographic geometry of Chasles . The general expression of the stigmatic relation is obtained by a generalization of Chasles 's fundamental lemma in his theory of characteristics ( Comptes Rendus , June 27 , 1864 , vol. lviii . p. 1175 ) , clinants being substituted for scalars* . It results that in certain forms of the law of coordination , which " coordinates " the stigmata with the indices , there may be solitary indices which have no corresponding stigmata , and solitary stigmata which have no corresponding indices , and also double points in which the index coincides with its stigma ( 76)t . The particular case in which one index corresponds to one stigma and conversely , and no solitary index or stigma occurs , is termed a stigmatic line ( henceforth written " s. line " ) , because the Cartesian case is that of a Cartesian straight line in ordinary . coordinate geometry , but in the general s. line the figures described by index and stigma may be any directly similar plane figures ( 77 ) . The investigation of this particular case occupies almost the whole of the Introductory Memoir . When one index corresponds to one stigma and conversely , but there is one solitary index and one solitary stigma , we have s. homography , provided the solitary index is distinct from the solitary stigma ( 79 ) , and s. involution when the solitary index coincides with tl e solitary stigma ( 78 ) , so called because they generalize the relations treated of under these names by Chasles . When the relations between index and stigma are expressed by an equation of the second order , the s. curves are termed s. conics , because they include Cartesian conics as a particular case ( 80 ) . Generally two stigmata correspond to each index , and two indices to each stigma , and there is no solitary index or stigma . Two s. curves in.tersect when they have a common ordinate , and there* If 01 be any fixed axis of reference , and AB any line upon a fixed plane passing through OI , we may consider that a line equal in magnitude and direction to AB can be formed from OI by the operation of turning OI through the Z ( OI , AB ) , and altering its length in the ratio of the length of 01 to that of AB . When all such lines AB lie upon the same plane , this operation is termed a clinant and represented by ab to distinguish it from the line AB . If the lines AB lay on different planes , the operation would be in general a quaternion . But if AB is parallel to 01 , whatever be the plane on which it lies , the operation ab is termed a scalar . Clinants and scalars obey the laws of ordinary commutative algebra . Quaternions do not . t The figures in parentheses refer to the articles of this " Second Memoir , " which are numbered consecutively to those in the Introductory Memoir ( Proceedings , April 6 , li)5 , vol. xiv . p. 176 ) . 1866 . ] 193 fore a common s. point . They touch when a slight alteration in the constants of one equation will make one of their common s. points into several , having their stigmata very near . When they have no common ordinate or s. point , they are parallel or asymptotic , according as the distances between the stigmata corresponding to a common index remain unchanged or , under certain circumstances , diminish infinitely ( 81 ) . It has been shown in the Introductory MVemoir that a s. line can be determined by two stigmata corresponding to known indices , or by two points called the direction-point and original stigma* . Taking either the two first-named or the two last-named points as the index and stigma in a stigmatic relation , we are able to make its expression denote a linear relation , which leads to the conception of enveloped s. curves , and therefore of classes of s. curves ( 82 , 83 ) . In the above relations two ordinary geometrical points ( " g. points " ) in a plane form the index and stigma . If we now take two s. points ( that is , two relations of index to stigma ) , terming one primary and the other secondary , we are able , by means of two equations , to express a relation between these s. points , so that one primary shall correspond to n secondaries , and one secondary to m primaries . This is the bipunctual relation ( 84 ) , and includes the whole subject of related s. curves , of which related Cartesian curves form a particular case . The most important and elementary cases are , first , those in which the related s. points lie respectively on known s. lines , s. involutions , s. homographies , or s. circles , and there is a stigmatic relation between the stigmata considered as forming two groups , one of indices and one of stigmata ; and secondly , those in which one primary s. point corresponds to one secondary and conversely . In the latter case the relations between one index and stigma may be inferred from known relations between another index and stigma , or from the same index and a new stigma , or , as is most usual , from the same stigma and a new index . Hence follows the general theory of change of coordination ( 85 ) . Homographic and homologic s. figures ( b6 ) are another example , in which one primary corresponds to one secondary s. point and conversely ; but there is generally one solitary s. line in aach s. figure such that no s. point taken upon it will have any corresponding s. point in the other figure . Corresponding to the bipunctual relation there is a bilinear relation ( 87 ) in which one primary s. line corresponds to several secondary s. lines , and one secondary to several primaries , by means of the elements chosen to represent linear relations . To this belongs the biradial relation ( 87 b ) , where two pencils of s. rays , being drawn from known s. points , are determined generally by s. points having a bipunctual relation , and exceptionally by their direction-points only , so that the relation between the rays can be expressed by a stigmatic relation between the direction-points considered as indices and stigmata . When this s. relation between the directionpoints is a s. homography , we have pencils of homographic s. rays . The reciprocal relation , in which a s. point corresponds to several s. lines , and a s. line to several s. points , follows immediately ( 88 ) . Finally , the multindicial relation ( 89 ) shows how several indices may be made to correspond as one group to a single stigma or a group of stigmata , and thus leads to the geometrical expression of the algebraical theories of several independent variables . The means by which a theory of solid stigmatics , where the indices and stigmata are taken anywhere in space , may be expressed by quaternion equations is briefly pointed out ( 89 e ) . The systematic explanation and precise expression for all these relations , together with some convenient notations relating especially to s. angles * ( 90 ) , and to anharmonic ratios ( 91 ) , occupy the first part of the present memoir . The remaining two divisions are devoted to a somewhat fuller consideration of s. homography ( including s. involution ) and s. conics . It results ( 92 ) from the conception of s. involution , already givein , that if S be the coincident solitary index and solitary stigma , and X , Ya corresponding pair of index and stigma , that is , if ( xy ) is a s. point on the s. involution , there will be two points , E , F ( called double stigmata ) , in the same straight line with S , in which index and stigma coincide , forming the double points ( ee ) , ( ff ) , and then seS=sf2=sx.sy , which implies that Z XSE =L ESY , and Z XSF =Z FSY , and also that each of the lengths of SE , SF is a mean proportional between the lengths of SX and SY . It is readily shown that the two cases of involution of points in a line , usually acknowledged , are but the particular cases of XY lying on the line OF , or on a line through S perpendicular to OF . In the former case the double points lying on the line containing XY were readily found , and hence termed " real ; " in the latter , as the method of investigation did not suffice to determine the double points , they were termed " imaginary . " If A , B , C , D be any four indices , and A ' , B ' , C ' , D ' their corresponding stigmata in a s. involution , then ab . cd a'b ' . c 'd ' ab . cc ' a ' ' . c'c and - ; -T = _ , ad . cb = ad ' c'b " ac ' cb a'c . c'bb that is , the anharmonic ratiot of any four indices is the same as that of their corresponding four stigmata , and the anharmonic ratio of any three indices and stigma is the same as that of the corresponding three stigmata and index in a s. involution . If the index move on the characteristic circle whose centre is S and radius SE , the corresponding stigma moves in the opposite segment of the same circle , and in an opposite direction of rotation . Generally if the index move on any circle passing through E , F , the stigma moves on the segment of the same circle lying on the other side.of OF , and in the opposite direction of rotation . If the index moves on a straight line passing through S , the stigma moves on another straight line also passing through S. If the index move on a straight line not passing through S , the stigma moves on a circle passing through S and conversely . If the index moves on a circle not passing through S , the stigma moves on another circle also not passing through S , and in an opposite direction of rotation . If the whole group of stigmata be removed without disturbing their mutual relations , and so that the solitary index S no longer corresponds with the solitary stigma Z ' , a s. homography results ( 93 ) , in which the relations of index and stigma may be deduced from those in a s. involution . These relations are expressed by the equation s. z'y = sa . z'a ' , where ( xy ) , ( aa ' ) are s. points in the s. homography . When three s. points are given , the solitary index S , and solitary stigma Z ' , and double stigmata E , F can be determined by an elementary geometrical construction in all cases . These double stigmata possess important anqgular properties with respect to the indices and stigmata of the system ( 94 ) . Let ( aa ' ) , ( bb ' ) , ( cc ' ) be any three s. points in a s. homography . Then if ABC , A'B'C ' are straight lines ( in which case the former contains S , and the latter Z ' ) , tan AEA'= tan BEB ' ; that is , if two intersecting straight lines EA , EA ' revolve about their point of intersection E , and cut two given straight lines AB , A'B ' , determining an index A upon one , and a stigma A ' upon the other , so that the ordinate AA ' is seen under an angle whose tangent is constant* , the s. points will form part of a s. homography , of which the given point E is one double stigma , the solitary index S lying upon the index line AB , and the solitary stigma Z ' upon the stigma line A'B ' . If 0 be the middle point of SZ ' and F the other double stigma , FO=OE . If the two lines AB , A'B ' coalesce , then the two points E , F , fromw which the ordinates AA ' , BB ' , CC ' of three or more s. points , of which both indices and stigmata lie upon one straight line , are seen under an angle whose tangent is constant , are the double stigmata of the s. homography determined by these three s. points . This shows the nature of the points named in G. S. 171 t , and completes it , so far as " real rays " are concerned . It is further generalized hereafter . The two lines AB , A'B ' may be so placed that the s. homography has only one ( louble stigma O coinciding with the middle point of SZ ' , and O will then be the centre of a circle of which AB , A'B ' are tangents ; the ordinates of the s. points in the s. homography ( each of which contains an index and a stigma ) will then be tangents to the circle of which the centre ( being a double stigma ) will also contain an index and stigma . Hence is immediately obtained the relation in G. S. 664 , and an explanation of the remark there made , that " le centre du cercle tient lieu en quelque sort d'une tangente . " The tangent of the angle subtended by an ordinate at the double stigma may be constantly zero , that is , the ordinates may converge to the double stigma . Then , if through any point E two straight lines be drawn , and through any other point F rays be drawn intersecting the first line in a series of indices A , B , C , and the second in a series of stigmata A ' , B ' , C ' respectively , the resulting s. points ( aa ' ) , ( bb ' ) , ( cc ' ) willform part of a s. homography of which E , F are the double stigmata . This shows the nature of the points of issue and intersection in the fundamental proposition of anharmonic ratios , G. S. 14 , and completes it so far as " real " rays are concerned . It will be further generalized hereafter . Hence ABB'A ' is a quadrilateral , of which E , F are the intersections of opposite sides . Consequently if A , B ' and A ' , B are opposite vertices of a quadrilateral , and E , F the intersections of the opposite sides ( ab ' ) , ( a'b ) , ( of ) are s. points in a s. involution . This completes G. S. 350 , for " real " rays * . The above considerations determine all the relations of s. homography , but do not suffice to give an explanation of those " imaginary " rays which play so important a part in Chasles 's geometry . The requisite theory is very simply obtained by considering the direction-points of two sets of ( primary and secondary ) s. rays as indices and stigmata in a s. homography or s. involution ( 95 ) . In particular it is shown that if the s. tangent of the s. angle between two primary s. rays is equal to that between the two corresponding secondary s. rays , there are two pairs of parallel s. rays , which are parallel to the asymptotes of a s. circle ; and all the other relations for pencils of ordinary homographic rays are similarly generalized . In this case , if the direction-points of all the rays lie upon the same straight line passing through the origin , the s. rays correspond to those usually termed " real ; " and if any do not , the s. rays belong to the class usually termed " imaginary , " and were supposed not to have any geometrical existence . When the two s. points of issue of the two pencils are distinct , there will be generally two primary rays which are parallel to their secondaries ; and if the two s. points of issue coincide ( 96 ) , these parallel rays will become double rays . Both are found by finding the double points of the homography of direction-points . When the double rays are s. perpendicular* , the sum or difference of the s. tangents of the two s. angles made by the primary and its corresponding secondary with the double rays will be zero . If the direction-points form a s. involution , the s. rays form an involution , and there will be always two s. rays s. perpendicular and easily constructed . The stigmata of the s. points in which the primary and secondary s. rays of two pencils , making the s. tangent of the s. angle between such rays constant , intersect two given s. lines , are indices and stigmata respectively of s. points in a s. homography , of which the stigma of the point of issue is a double stigma ( 97 ) . Whence it follows that , in any s. homography , if the indices be considered as the stigmata of s. points on a known s. line , and the stigmata as the stigmata of s. points on some other known s. line , and a second index be given to one of the double stigmata so as to form a s , point which shall lie upon neither of those given s. lines , and pairs of s. rays be drawn from the s. point thus formed to pairs of corresponding s. points in the two s. lines , the s. tangent of the s. angle between any two corresponding rays will be constant . Supposing each primary s. ray to coincide with its secondary , and OI to be the axis of reference ( 98 ) , the stigma of the s. point of issue of a pencil of s. rays , and the stigmata of the intersection of these s. rays with a given s. line , form the indices , and the extremity I of the axis of reference OI , and the direction-points of the same s. rays , respectively form the stigmata of a series of s. points in a s. homography . Whence it follows that the anharmonic ratio of any four stigmata of intersection is the same as that of the four corresponding direction-points . This completely generalizes the fundamental proposition of anharmonic ratios , including the case where all the lines are " imaginary , " and can be made the starting-point of a series of propositions precisely analogous to those in G. S. , but with a much wider signification . Thus the property of the complete quadrilateral shows , on being generalized , that if E , A , B , C , D , Et , A ' , B ' be any eight points upon a plane , and two other points C ' , D ' be assumed so that the triangles E'A'C ' , E'B'D ' shall be directly similar to the triangles EAC , EBD respectively , and then two additional points F ' , F be determined so that the triangles FA'B ' , F'C'D ' shall be directly similar to the triangles FAB , FCD , the point F will be constant , if the first five points E , A , B , C , D remain unchanged , whatever the next three , E ' , A ' , B ' , may be , and will lie so that if SM be drawn bisecting the angles ASD , BSC and in length a mean proportional between the lengths of SA , SD , and also of SB , SC , then SM will also bisect the angle ESF , and be in length a mean proportional between SE and SF . When pairs of separate s. rays cutting one s. line are considered , it is shown ( 99 ) that if from any point pairs of ordinary rays be drawn which are the two limbs of a constant angle cutting any straight line in points forming the indices and stigmata of s. points in a s. homography of which the point of issue is a double stigma , and we furnish all the points lying on the given straight line , and the point of issue , with Cartesian indices , and hence consider all the s. rays as Cartesian , they willform part of an homography of s. rays , of which the double rays drawn from the Cartesian point of issue will be two non-Cartesian s. lines parallel to the asymptotes of a s. circle , and therefore independent of the magnitude of the constant angle . This furnishes a complete geometrical explanation of G. S. 171 , 172 , 181 , 651 , S.C. 293 , &c. Generally the whole of the propositions in G. S. respecting the homography of ordinary points and rays may be transferred to the homography of the stigmata of s. points and of s. rays , forming a series of propositions of much greater generality , in which all the s. points and s. rays will be perfectly real , and can be constructed by means of elementary geometry . The last division of this memoir is devoted to s. conics , which embrace the ordinary Cartesian conics as particular cases , together with all their so-called " imaginary " points and lines . The general equation is assumed ( 100 ) in the form or . 2o + 2o 3 . ox.oy +o . oy2+2o . ox+2 2oe . oy + o= 0 ; . ( a ) and it is shown that if of'= oa . oy the equation may represent a single s. line , or two parallel s. lines , or a s. acentric , which , by changing the origin and index , may be made to depend on the equation x'y2=4s'o ' . o ' ' ; but if oj32 is not = oa . oy , the equation may represent two intersecting s. lines , or a s. centric-that is , a s. curve which when cut by any s. line passing through a given s. point ( the s. centre ) has the index and stigma of that s. point in the middle of the lines joining the two indices and two stigmata of the s. points of intersection respectively . ' It is also shown that if the origin and index are changed , the s. centric may be represented by the equations 2+ y= l , or o'x " . x"oy = o. ( b ) 0 e2 0O(2 in which case the s. lines ox'= O , x'y 0 are indeterminate , but form pairs ofs . rays in involution , which are all conjugate diametrics* , with the exception of the double rays o'"=0 , x"y =0 , which are asymptotes . In the particular case that o =-0 , the general equation can , by changing origin and index , be made to depend on the equation ox'2-x'y2= o'e2 . Such curves are called s. cyclics . In the cyclic proper , the values of ot3 , oy may be any whatever ; in the s. circle o+ oy =0 , in which case all the conjugate diametrics are s. perpendicular , and the direction-points of the asy ptotes are I , I ' . But if both oa and ox become = 0 , the s. cyclic is a s. homography or s. involution . The general homographic properties of all s. conics are then deduced ( 101 ) . First , a s. conic is the locus of the s. points of intersection of the primary and secondary s. rays of two pencils of homographic s. rays with different s. points of issue , and passes through these points , which , with slight modifications , holds when a band of parallel s. lines is substituted for either or both of the pencils . Secondly , the anharmonic ratio of four s. chords in a s. conic drawnfrom a variable s. point tofour fixed s. points , bears a constant ratio to the anharmonic ratio of the stigmata of thosefourfixed s. points ; and this constant ratio is one of equality when the s. conic is a s. circle . In order to establish the latter part of this proposition , it is shown that in a s. circle , the s. tangent of the s. angle formed by any two s. rays drawn from a variable s. point to any two fixed s. points in the s. circle is constant ( which is a generalization of Euc . iii . 21 ) , whence is deduced the condition that four s. points should lie upon a s. circle . The classification of s. centrics is founded ( 102 ) on the first of the equations ( b ) . After showing how the two stigmata can be generally found from the index , the name of the s. centric is made to depend on the name of the locus of the stigma when the index describes the principal diameter in whole or in part . This locus is called the characteristic curve . According as o'e + o'g2 is a negative scalar , -1 , a positive scalar , + 1 , or any clinant , the s. centric is a s. ellipse , circle , hyperbola , equiradial ( equilateral hyperbola ) , or hyperellipse ( for which the characteristic is a confocal ellipse and hyperbola ) . The mode of finding the two indices corresponding to each stigma is then given ( 103 ) , and the circumstances under which a s. line and a s. centric may have common points investigated ( 104 ) . The mode of determining s. points of intersection , when there is no intersection in Cartesian geometry ( " imaginary " intersections ) is illustrated , and shown to lead to the same results as the homographic method . The radical axis ( 105 ) is shown to be the Cartesian portion of a s. line which is the common s. chord of a series of s. circles , so situated that the extremities of their principal diameters are the indices and stigmata of a s. involution , of which the " real " and " imaginary " circles of Chasles are two particular cases . The properties of asymptotes , and the nature of those in a s. ellipse , are then considered ( 106 ) , and their geometrical properties examined . Conjugate Diametrics and their relations to the asymptotes are next investigated , ( 107 ) . In especial it is shown that if ( u'e ' ) , ( v'g ' ) are two of the s. points in which two conjugate diametrics intersect a s. centric , and if the s. line drawn from ( u'e ' ) s. perpendicular to the diametric connecting ( o'o')and ( v'g ' ) meet the latter in a s. point whose stigma is D , we shall have ou ' . u'e ' +o'v'.'=0 , ... ... ... . . ( c ) o'u2 +o ' / 2 'e2 , u'e2+ v ' =og , ... ... ( d ) whence o'e'2+o'g'=o'e+o g2 ... ... . . ( e ) and de ' . ( o'v-v'g ' ) f+o'e o'g ... ... . . ) 200 [ June 14 , From these relations , which are much more general than any hitherto enunciated , the ordinary relations in Cartesian geometry respecting the lengths of conjugate diameters and the areas they contain are readily deduced . By referring s. centrics to conjugate diametrics as new coordinate axes ( 108 ) , a simple general method for constructing the intersections of a s. line with a s. centric , and for drawing two s. tangents ( 109 ) from any s. point ( except the s. centre ) is obtained . This is illustrated by actual geometrical constructions corresponding to " imaginary " cases in Cartesian geometry . It is also shown how the chord of contact or polar may have a Cartesian portion when both the s. points of contact are non-Cartesian and hence " imaginary . " It is now possible ( 110 ) to demonstrate the fundamental anharmonic properties of tangents and asymptotes to a s. centric . If through four s. points in a s. centric , four tangents be drawn , intersecting any fifth tangent , and also four s. chords meeting in any fifth s. point in the s. centric , the anharmonic ratio of the four stigmata of the s. points of intersection of the four tangents with the fifth will be equal to the anharmonic ratio of the four s. chords ( which generalizes S. C. 2 , 5 , the demonstration being here direct and therefore widely differing from Chasles 's ) , whence , if twofixed tangents are cut by a moveable tangent the stigmata of its s. points of intersection with them will be the indices and stigmata of s. points in a s. homography . It is now possible to generalize the whole of Chasles 's S. C. , and make the theories applicable , mutatis mutandis , to s. conics . The s. foci of a s. centric ( 111 ) are defined as the s. points of intersection of any two tangents which are parallel to the asymptotes of a s. circle . Hence it is shown that there are four s. foci to a s. centric ; so that if o's2=o'e2-+o'g'=o'z2 , the two principal s. foci are ( ss ) ( zz ) , and the two transverse s. foci are ( o 's ) , ( o'z ) . When the s. centric is Cartesian , the two principal s. foci are those usually recognized , and the only two recognized by Chasles , S. C. 275 , 294 . The other two transverse s. foci have , however , been recognized as " imaginary " foci by Plucker ( System der a. Geometric , p. 106 , 1 . 6 ) , and by Salmon ( Conics , 4th ed. p. 242 ) . Besides the usual properties of the focal stigmata in Cartesian curves , the following entirely new correlative properties of the principal and transverse s. foci are demonstrated . Let there be two conjugate diametrics , and through any s. point in one draw a s. line parallel to the other , and let the stigmata of the s. points of intersection of the conjugate diametrics and the chord , with the s. centric , be respectively E ' , F ' ; G ' , H ' ; Yx , Y2 . From E , F ' draw straight lines PARALLEL to the bisectors of the angles Y1SY2 , YZY2 respectively , forming two sides of a triangle of which E'F ' is the base . Then the lengths of these sides will be mean propor . tionals between the lengths of SY1 , SY , , and ZY1 , ZY , respectively . This is a generalization of the usual property that the sum or difference of the s focal distances is the axis major in the ellipse or hyperbola . Preserving the same notation , take X ' the middlepoint of Y1Y2 , set o'f X'X3=X4X ' =O'S , and make X3Y"=Y2X3 , and XY " ' =Y-X4 . From the extremities G ' , Hi ' of the diameter CONJUGATE to that used in the last proposition , draw straight lines PERPENDICULAR to the bisectors of the angles Y"SY2 , Y"'ZY2 respectively , forming the two sides of a triangle of which G'H ' is the base . Then the lengths of these sides will be mean propor . tionals between the lengths of SYi , SY2 and ZY"t , ZY2 respectively . This is the correlative property of the transverse s. foci , which has no Cartesian analogue . The deduction and expression of these properties is extremely simple , and they are illustrated by a geometrical construction . Finally , the s. tangent of the s. angle which the s. rays drawn from any s. point in a s. centric to the two principal or the two transverse s. foci make with the s. normal at the s. point are equal and opposite , which is a generalization , for both pairs of s. foci , of the property from which the ordinary foci derived their name . The following problems are then solved ( 112 ) . First . Given two conjugate radii O'E ' , O/ 'G to find the principal and transverse axes of the Cartesian centric . The focal stigmata S , Z are found from ( e ) thus : from E ' draw E'M~ , E'tM perpendicular to 0'Gt , and equal to it in length ; join O'M , OI'M , bisect the angle MOW'M by 0'S , OtZ , which are in length mean proportionals between O'M , O'M ' . Then there are three solutions , giving an ellipse or two hyperbolas , according as both or only one of the conjugate radii meet the characteristic curve of the Cartesian centric . Second . Given any three s. points representing the s. centre , and the s. points of intersection of two conjugate diametrics with the s. centric , to find its principal and transverse axes . Third . Given three s. points , to find the axis of a s. circle passing through them . Fourth . Given any five s. points , to determine whether they lie on a s. centric ; and if so , to find its principal and transverse s. axes . Equation ( e ) is then applied ( 113 ) to obtain a more general conception of confocal s. centrics , and Carnot 's theory of transversals ( as generalized in the Introductory Memoir ) is applied to finding a new expression for the s. radius of curvature , applicable for any s. point of contact . The ordinary expression gives length and not direction , and applies only to Cartesian points . Similar investigations are very briefly given for s. acentrics ( 115-118 ) . In these memoirs on Plane Stigmatics , the writer has endeavoured to confine himself strictly to such a development of his theory as would suffice to establish , with geometrical severity , the following results , which he believes to be entirely new , and of great scientific importance to mathematics . First . The problem of the geometrical signiflcation of imaginaries in plane geometry is completely solved ; so that the terms " r eal " and " imaginary " are no longer required , and an unbroken agreement exists between plane geometry and ordinary commutative algebra . [ Julne 14 , 20 Imaginaries arise whenever an algebra is used which is more general than the geometry to which it is referred . Ordinary commutative algebra is an algebra of clinants , which corresponds to a geometry where not only the relative lengths , but the relative angular positions of straight lines are regarded . Now the geometry hitherto associated with it has been scalar , that is , has considered relative lengths , but only identity or opposition of direction . Thus in Cartesian geometry the abscissre and ordinates were necessarily supposed to be parallel to given lines ; and in homographic geometry , where the ordinates were not taken into account , their extremities were supposed to lie on one or two given lines . But the algebra employed in either case took no notice of these restrictions , and hence led to results which could not be interpreted-that is , " imaginaries . " The solution of the problem of imaginaries has , therefore , consisted in that stigmatic conception which removes these restrictions , freely introduces relative angular position , and makes the geometry coextensive with the algebra . In the course of these memoirs every fundamental case in which imaginaries occur has been separately examined and shown to be fully explained by this conception . Second . The coordinate geometry of Descartes , and the homographic geometry of Chasles , are only particular cases of the writer 's stigmatic geometry , identical in nature , and expressible by identical equations ; for both Cartesian and homographic geometry consist in the relation of index to stigma with various restrictions , which may or may not be regarded in stigmatic geometry . Third . The general theories of plane curves , as treated by ordinary coordinate geometry , by the systems of coordination introduced by Plucker , or the modes of investigation more recently developed by Chasles , and all the theories derivable from these , hold , IN THEIR INTEGRITY , for stigmatic curves ALONE . For in all these theories clinant algebra is associated with scalar geometry , for which the stigmatic conception enables us to substitute that clinant geometry which perfectly agrees with the algebra employed ; and the fundamental propositions of these theories have been extended accordingly in the course of these memoirs . The instrument by which the writer has been enabled to bring these investigations to a successful issue , has proved so serviceable and manageable , embracing old and new properties in a single equation , often rendering a general investigation more easy to conduct than the former special researches , and keeping the geometrical operations indicated clearly before the mind , that he would add as a subsidiary result of his theory : Fourth . A calculus and a notation have been invented and developed , which enable magnitude and direction upon a plane to be expressed by a single symbol , obeying the laws of ordinary algebra , closely resembling in appearance ( not in theory ) the notation employed by Chasles to represent magnitude and direction upon a straight line , and as easy of manipulation , 1866 . ] 203

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Fundamental Views regarding Mechanics. [Abstract]

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208

Proceedings of the Royal Society of London

Julius Pl\#xFC;cker

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6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112615

http://www.jstor.org/stable/112615

Formulae

Fluid Dynamics

Mathematics

III . " Fundamental Views regarding Mechanics . " By Professor JULIUS PLU/ CKER , of Bonn , For . Mem. R.S. Received May 29 , 1866 . ( Abstract . ) Being encouraged by the friendly interest expressed by English geometricians , I have resumed my former researches , which had been entirely abandoned by me since 1846 . While the details had escaped from my memory , two leading questions have remained dormant in my mind . The first question was to introduce right lines as elements of space , instead of points and planes , hitherto employed ; the second question , to connect , in mechanics , both translatory and rotatory movements by a principle in geometry analogous to that of reciprocity . I proposed a solution of the first question in the geometrical paper presented to the Royal Society . I met a solution of the second question , which in vain I sought for in Poinsot 's ingenious theory of coupled forces , by pursuing the geometrical way . The indications regarding complexes of forces , given at the end of the " Additional Notes , " involves it . I now take the liberty of presenting a new paper , intended to give to these indications the developments they demand , reserving for another communication a succinct abstract of the curious properties of complexes of right lines represented by equations of the second degree , and the simple analytical way of deriving them . 1 . We usually represent a force geometrically by a limited line , i. e. by means of two points ( x ' , y ' , z ' ) and ( x , y , z ) , one of which ( x ' , y ' , ' ) is the point acted upon by the force , while the right line passing through both points indicates its direction , and the distance between the points its intensity . We may regard the six quantities - ' , y-y ' , --z ' , yz'-y'S , zx'-z'x , xy'--xy ... . ( 1 ) as the six coordinates of theforce . The six coordinates of a force represent its three projections on the three axes of coordinates OX , OY , OZ , and its three moments with regard to the same axes . Accordingly we may , as far as we do not regard the point acted upon by the force , replace its coordinates by X , Y , Z , L , M , N ... ... ... ... . . ( 2 ) in admitting the equation of condition LX+MY+NZ=O , ... ... ... ... ... ... ( 3 ) which indicates that the axis of the resulting moment is perpendicular to the direction of the force . In making use of the primitive coordinates this condition is involved in the form given to them . When the last condition is not satisfied , the coordinates X , Y , Z , L , M , N represent no longer a mere force ; they are the coordinates of what I proposed to call a dyname . In the general case such a dyname results when any numbers of given forces act upon any given points . Here the six coordinates of the dyname are the sums of the six coordinates of the given forces ( x ' , y ' , ' , , y , ) . If between the six sums thus obtained , 2(X-x ' ) , 2(y-y ' ) , 2 ( - , ' ) , ( 4 ( yz'-y'z ) , ( zx'-z'x ) , ( xy'-x'y ) , ... ... an equation analogous to ( 3 ) takes place , there is a resulting force . In the case of equilibrium the six sums become equal to zero . 2 . In quite an analogous way as we have determined an ordinary force by means of two points in space , one of which is the point acted upon , we may represent a rotation , or the rotatory force producing it , by means of two planes , t'x + 'y + v ' = , tx+uy + vz=l , the coordinates of which are t ' , u ' , v ' and t , u , v , one of the two planes ( t ' , u ' , v ' ) being the plane acted upon . The right line along which both planes meet is the axis of rotation . The plane acted upon may in a double way turn round the axis of rotation in order to coincide with the second plane ( t , u , v ) ; but there is no ambiguity in admitting that during the rotation the rotating plane does not pass through the origin , and consequently its coordinates do not become infinite . Let us regard the six quantities t-t ' , U , uv-v ' , zv'-u'v , vt'-v't , tu'-t'u ... ... ( 5 ) as the six coordinates of the rotatory force . As far as we do not regard the plane acted upon , we may replace them by X , ? ) 3 , 3 , 9 ) , ( , ... ... ... ... . . ( 6 ) in admitting the equation of condition , +9J2)+ 3 *-*= 0 ... ... ... ... ... ... ... ( 7 ) ( For the geometrical signification of these new coordinates I refer to the original paper . ) When the last equation of condition is not satisfied , the coordinates X , 9 ) , ? 3 , 9J , 9t no longer represent a mere rotatory force ; they are the six independent coordinates of what I called a rotatory dyname . In the general case , such a rotatory dyname results when any number of given rotatory forces acts on any given planes . IIere the six coordinates of the resulting rotatory dyname are the six sums of the six coordinates of the given rotatory forces . E2(t-rt ) , ; ( u-u ' ) , ( v-- ' ) , ( 8 ) Z(UV'--u'v ) , M(vt'-vt ) , ( t-t'u ) ... ... . . If between these six coordinates the equation of condition subsists , there is a resulting rotatory force . In the case of equilibrium the six sums become equal to zero . Any movement whatever may be referred as well to ordinary as to rotatory forces ; consequently an ordinary dyname and( a rotatory dyname mean the same . 3 . From the notions developed we immediately obtain two general theorems constituting the base of statics . In a similar way as d'Alembert 's principle is derived from the " principe des vitesses virtuelles , " both theorems may be transformed into fundamental theorems of mechanics . In starting from the coordinates of ordinary forces , the equations of equilibrium are:s( , - ) =O , 2(y-y ' ) =0 , ( z- : z ' ) =0 , l ( O ) ( yz'-y'z)=0 , 2(zx'--'x)=0 , s( y''y_)=0 , " which , by replacing these forces by rotating ones , become ( t-t ' ) =0 , E ( u-u ' ) =0 , X(v-v ' ) =0 , . ( 10 ) z(uv'-u'v)=0 , :(vt'-vt ) =0 , E(tu'-t'u ) = . J We likewise may express the conditions of equilibrium by the following six equations( , --')= 0 , S(y-y ' ) =0 , ( z--z')=0 , }..l 2(t-t ' ) =0 , 2(U-u')=0 , 2(V-V')=o , " ( three of which are taken amongst ( 9 ) , three amongst ( 10)-and expand these equations in the analytical way , starting either from the consideration of ordinary or rotatory forces . The interpretation of these equations immediately gives the following two theorems . In the case of equilibriumI . The centre of gravity of the points acted upon by the forces coincides with the centre of gravity of the second points , by means of which the forces are determined ( No. 1 ) . II . The central plane of the planes acted upon by the rotatory forces coincides with the central plane of the second planes , by means of which the rotatory forces are determined ( No. 2 ) . If we introduce the notion of masses , both theorems hold good , only the definition of both kinds of forces and therefore their unity is changed . The points acted upon become centres of gravity corresponding to masses ; the planes acted upon , central planes corresponding to moments of inertia . If equilibrium does not exist , we get , in the general case , one resulting force , determined by the two centres of gravity , and one resulting rotatory force determined by the two central planes . We easily obtain the six differential equations of the imovement produced . I shall think it suitable further to develope the principles merely indicated in the paper presented . A Treatise on Mechanics , reconstructed on them , will assume quite a new aspect . 4 . In making use , within a plane , of pointor line-coordinates , we represent , by means of an equation between the two coordinates , a plane curve described by a point , or enveloped by a right line . In making use , in space , of pointor plane-coordinates , by means of an equation between the three coordinates , a surface is represented which may be regarded as a *The coordinates of the central plane are obtained in the same way by means of the coordinates of the given planes as the coordinates of the centre of gravity are obtained by means of the coordinates of the given p6ints . locus of points , or an envelope by planes . In my geometrical paper I introduced the right line , depending on four constants , as the element of space . An equation between these constants , if regarded as variables , represents a complex of lines . Each line of the complex maybe regardedeither as a ray described by a point , or as an axis enveloped by planes . In order to render the developments symmetrical , I adopted as coordinates of the right line the same expressions ( 1 ) and ( 4 ) ( connected by an equation of condition ) made use of in the determination of ordinary and rotatory forces . At the same time , general equations between the six coordinates were replaced by homogeneous ones . In doing so , A , B , C , D , E , F denoting any six constants , A(x--x ' ) +(y-y')+ C(z-z')+D(yz'y'z ) ... ... ( 2 ) I ... ... . . } ... ( 12 ) +E(yx'-y'x ) +F(xy'+x'y ' ) -=O , J* A(uv'-u'v ) +B(vt'--v't ) +C(tu't ' u ) +D(t-t')+E(u-u')+F(v-v ' ) O J. * ( 1**** represent the same linear complex of lines , which may be regarded as a complex of rays as well as a complex of axes . When general equations between the same six coordinates are admitted , the complex of rays becomes a complex of ordinary forces , the complex of axes a complex of rotations or rotatoryforces , both ordinary and rotatory forces depending upon five constants . Here we meet a reciprocity between both kind of forces corresponding to the reciprocity between point and plane . Finally , in omitting the equation of condition hitherto made use of , we pass from forces to dynames , depending upon the six independent constants X , Y , Z , L , N , N , ... ... ... . . ( 14 ) or , , 3 , ... ... ... ... ... ( 15 ) A complex of dynames is represented by an equation between six variables . I-ere again , as in the case of right lines , the same complex may be represented in a double way by means of the two sets of coordinates . In order to complete these general considerations , we add the following . A dyname may be resolved into two variable forces , either ordinary or rotatory . These variable forces constitute a linear complex , either of ordinary or extraordinary forces . A homogeneous equation between the six independent coordinates ( 14 ) or ( 15 ) represents a complex of two coupled variable right lines . 5 . I will conclude by giving some details regarding complexes of the first degree . A linear complex of ordinary forces is represented by the linear equation ~== 1 , which may be expanded thus : ( A + Fy'-Ez ' ) x+ ( BFx'--Dz')y ( + ( C +Ex'-.Dy')z In putting x ' , y ' , z ' as constants , those forces of the complex are obtained which pass through the given point ( x ' , y ' , z ' ) . In this supposition the equation of the complex becomes the equation of a plane . This plane is the locus of the second points , by means of which the forces of the complex are determined . Hence in a linear complex there are acting on each point of space forces in all directions , the intensity of each force being the segment on its direction between the point acted upon and its corresponding plane ( 16 ) . Hence we derive the following theorem : In a complex of rotatory forces any given plane of space is acted upon by an infinite number of forces , each line within the plane being an axis of rotation . The rotations round all axes are determined by second planes passing through a fixed point , the position of which depends upon the given point . I showed in the geometrical paper the way of discussing linear complexes of right lines . The properties of linear complexes of forces , either ordinary or rotatory , may be developed in a similar way . 6 . Right lines belonging simultaneously to two complexes constitute a single congruency , and accordingly intersect two fixed lines ; if belonging to three complexes , they constitute a double congruency , i. e. one generation of a hyperbolic or parabolic hyperboloid . Forces , either ordinary or rotatory , belonging simultaneously to two , three , four complexes , constitute a single , double , or threefold congruency of forces . In admitting these denominations , the following results arc immediately obtained . In a linear congruency of ordinary or rotatory forces , the directions of all ordinary , or the axes of all rotatory forces , constitute a linear complex of lines . All ordinary forces acting on any given point of space are confined within the same plane ; the intensity of each force is equal to the distance between the point acted upon and the point where its direction meets a fixed line within the mentioned plane . The axes of all rotatory forces , acting upon any given plane of space , meet in a fixed point within that plane . There is a fixed line passing through the fixed point , round which the second planes of all forces turn when their axes turn round the fixed point in the given plane acted upon . In a double congruency of ordinary forces there is one force of given direction and intensity acting upon any point of space , as there is in a double congruency of rotatory forces one force acting upon any given plane . In a threefold congruency of ordinary forces the directions , in a threefold congruency of rotatory forces the axes of all forces constitute one of the two generations of a hyperboloid . These few indications may be sufficient here ; but before concluding I must , in referring to the original paper , make a last remark . Forces acting along a given right line may either be regarded as the same , whatever may be the point of the line acted upon , or they may be regarded as varying in intensity according to the position of the point . There is an analogous distinction to be made with regard to rotatory forces . Accordingly two different kinds of complexes must be distinguished . 208

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3701662

Contributions to Terrestrial Magnetism.--No.X. [Abstract]

209

209

Proceedings of the Royal Society of London

Edward Sabine

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112616

http://www.jstor.org/stable/112616

Biography

Meteorology

Biography

IV . " Contributions to Terrestrial Magnetism.-No . X. " By Lieut. General EDWARD SABINE , R.A. , President of the Royal Society . Received June 7 , 1866 . ( Abstract . ) In this number of the Contributions to Terrestrial Magnetism the author resumes the discussion of the results obtained in the Magnetic Survey of the Southern Ocean by the Expedition under Sir James Clark Ross , R.N. , and Captain Francis Rawdon Crozier , R.N. , between the years 1839 and 1843 . The proceedings during the two first years of this Survey have been the subjects of two preceding numbers of the Contributions , viz. of Nos. V. and VI . , in the Philosophical Transactions for 1843 and 1844 . The present number contains a similarly detailed exposition of the operations of the third year of the Survey , comprehending the Southern Atlantic between Cape Horn and the Cape of Good Hope , and completing the circumnavigation of the southern hemisphere , from the departure of the expedition from the Cape of Good IIope in March 1840 , to the return to the same station in April 1843 . In a subsequent memoir , which will be presented to the Royal Society early in the ensuing Session , the author proposes to connect and thoroughly coordinate the three portions of the Survey , and to supply from them the numerical data at equidistant points on each of the three parallels of 50 ? , 60 ? , and 70 ? of south latitude , of the three magnetic elements , which will be required for a revision of the 'Allgemeine Theory des Erdmagnetismus ' of M. Gauss the 40th parallel having been the most southern available at the epoch of the publication of the original work . The instruments employed in this Survey , as well as the methods of employing them , and of eliminating the disturbing influence of the iron in the equipment of the vessels , having been in a great measure of a novel character , a discussion of considerable length bearing on all such points is prefixed to a full detail of the observations themselves , arranged in Tables , showing in every instance both the immediate results of the observations , and the corrections which have been applied in conformity with the principles contained in the preliminary discussion . Tabular abstracts are also furnished , exhibiting the results of the determinations of each day , with the appropriate geographical positions .

112617

3701662

On the Relation of Rosaniline to Rosolic Acid

209

213

Proceedings of the Royal Society of London

H. Caro|J. Alfred Wanklyn

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0047

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112617

10.1098/rspl.1866.0047

http://www.jstor.org/stable/112617

Chemistry 2

Biography

Chemistry

IV . " Contributions to Terrestrial Magnetism.-No . X. " By Lieut. General EDWARD SABINE , R.A. , President of the Royal Society . Received June 7 , 1866 . ( Abstract . ) In this number of the Contributions to Terrestrial Magnetism the author resumes the discussion of the results obtained in the Magnetic Survey of the Southern Ocean by the Expedition under Sir James Clark Ross , R.N. , and Captain Francis Rawdon Crozier , R.N. , between the years 1839 and 1843 . The proceedings during the two first years of this Survey have been the subjects of two preceding numbers of the Contributions , viz. of Nos. V. and VI . , in the Philosophical Transactions for 1843 and 1844 . The present number contains a similarly detailed exposition of the operations of the third year of the Survey , comprehending the Southern Atlantic between Cape Horn and the Cape of Good Hope , and completing the circumnavigation of the southern hemisphere , from the departure of the expedition from the Cape of Good IIope in March 1840 , to the return to the same station in April 1843 . In a subsequent memoir , which will be presented to the Royal Society early in the ensuing Session , the author proposes to connect and thoroughly coordinate the three portions of the Survey , and to supply from them the numerical data at equidistant points on each of the three parallels of 50 ? , 60 ? , and 70 ? of south latitude , of the three magnetic elements , which will be required for a revision of the 'Allgemeine Theory des Erdmagnetismus ' of M. Gauss the 40th parallel having been the most southern available at the epoch of the publication of the original work . The instruments employed in this Survey , as well as the methods of employing them , and of eliminating the disturbing influence of the iron in the equipment of the vessels , having been in a great measure of a novel character , a discussion of considerable length bearing on all such points is prefixed to a full detail of the observations themselves , arranged in Tables , showing in every instance both the immediate results of the observations , and the corrections which have been applied in conformity with the principles contained in the preliminary discussion . Tabular abstracts are also furnished , exhibiting the results of the determinations of each day , with the appropriate geographical positions . June 21 , 1866 . Lieut.-General SABINE , President , in the Chair . Dr. Hugo Muller , Mr. Perkin , the Rev. Canon Selwyn , and the Rev. R. Townsend , were admitted into the Society . I. " On the Relation of Rosaniline to Rosolic Acid . " By II . CARO , and J. ALFREJD WANKLYN , Professor of Chemistry at the London Institution . Communicated by Dr. FIANKLAND . Received June 5 , 1866 . At the Meeting of the British Association held in Bath in the year 18G(1 , it was pointed out by one of us that rosaniline and rosolic acid might be represented as ethylene which had undergone substitution : Type . Rosaniline . llosolic Acid . T II OII NC0II IOCJI , 2{ I ; C)N C011 , 1 ' HJ0 CG III II I OIL Rosaniline and rosolic acid became members of the same family , the former being an ethylene containing N{ CiI5 in place of hydrogen , the latter also an ethylene , but containing O C , : II , and O II in place of hydrogen . Some of the reasons for assigning these formulm were given in the communication made to the Bath Meeting . The relationship between rosaniline and rosolic acid is very well brought out by the facts which will presently be brought forward . Griess has shown that aniline and nitrous acid yield water and diazobenzol : Aniline . Diazobenzol . C , II NI+H NO = C , II , N , , + 21 , 0 . Diazobenzol is a most remarkable compound , forming salts which are very explosive , and which undergo certain very interesting transformations under the influence of reagents . It is moreover the representative of a numerous class of compounds derived similarly by the action of nitrous acid on different bases , and for the most part resembling itself in the explosive character of the salts . One of the most remarkable reactions presented by diazobcnzol is that with water , wherein the whole of the nitrogen of the diazobenzol is evolved , and its place supplied by an atom of water : Nitrate of diazobenzol . Carbolic acid . C , I11N INO3 + II , O = CHO1 , + IINO +N , . This elegant form of reaction appears to be characteristic of the class to which diazobenzol belongs ; and Griess has resorted to a measurement of the quantity of nitrogen set free during the reaction , as a means of arriving at the composition of the azo-compounds . IIofmann showed , some years ago , that rosaniline , after treatment with nitrous acid , is capable of forming a platinum cormpound endowed with explosive properties , but appears not to have followed the investigation further . Paraf has recently sllown that rosaniline salts are converted by nitrous acid into a dye , which he considered to be rosolic acid . We have also investigated the action of nitrous acid on rosaniline , and arrive at the following results : When an acid solution of a salt of rosaniline is mixed with nitrous acid , it forms an azo-compound , which corresponds very closely in character to diazobenzol . Like diazobenzol this compound forms explosive salts ; like diazobenzol it decomposes with evolution of nitrogen gas when it is boiled with acids . In adding the nitrous acid to the solution of rosaniline to form the compound , it is easy to observe the exact point at which the solution ceases to contain unaltered rosaniline . It thus becomes easy to determine the amount of nitrous acid consumed in the conversion of a given weight of rosaniline into the azo-compound . We have done this by the employment of a method which gives excellent results when applied to aniline and toluidine , and the details of which will shortly be published by one of us . We obtain as the result of our experiments , that one molecule of rosaniline consumes three equivalents of nitrous acid ; and the equation representing the reaction will be Rosaniline . Azo-compound . C 11 N3+31-1 O , =N + 61,0.N C20 19 1N+3NN02 C20 oH0 N+ 6H1-12 . On boiling this azo-compound with hydrochloric acid , there is evolution of nitrogen gas . The volume of nitrogen was measured . The result was that one molecule of rosaniline , after conversion into the azo-compound , yields six equivalents of nitrogen . Azo-compound . C,20 -I , N+3 H,12 C0C 0 , ,03 + NG , These changes in composition are accompanied by striking physical effects . The deep-red solution of the salt of rosaniline becomes brown on the addition of excess of hydrochloric acid , then yellow as the nitrous acid is added ; then there is much froth , and as the solution is boiled it gradually becomes red yellow , and a large quantity of a deep-coloured solid with cantharides-like lustre separates out . Seeing that this solid is produced by treating rosaniline with three equivalents of nitrous acid , and that six equivalents of nitrogen are evolved , it must be a non-nitrogenous substance . A careful comparison of its properties and reactions with those of the rosolic acid described by Kolbe and Schmitt , and now made largely as an article of commerce , leads to the conclusion that it is identical with rosolic acid . The following characters are common to it and to the rosolic acid of Kolbe and Schmitt . 1 . A yellowish-red solid with cantharides-like lustre , only sparingly soluble in water , soluble in ether and alcohol . 2 . Easily soluble in ammonia , and in alkalies generally , forming red solutions of very great colouring-power . Addition of acids to these solutions decolorizes them , precipitating the colouring-matter in the form of a yellowish precipitate , which varies much in tint . 3 . When boiled with aniline and a little benzoic acid , it forms a blue dye , there being no evolution of ammonia . The blue dye is very soluble in alcohol , not soluble in water ; it is the salt of a red-coloured base . It dissolves in strong sulphuric acid , giving a red solution . 4 . Submitted to destructive distillation , it gives abundance of carbolic acid , leaving a carbonaceous residue . 5 . The deep-red solutions in alkalies are easily reduced on boiling them with zinc powder ; so treated they lose their colour ; but restoration of the colour takes place on adding fcrricyanide of potassium . There is only one particular in which any difference could be detected between the product obtained from rosaniline and that obtained from carbolic acid by Kolbe and Schmitt 's process . The rosolic acid of Kolbe and Schmitt forms salts the solutions of which are darkened by ferricyanide of potassium . The product obtained from rosaniline does not darken , or darkens only very slightly , on the addition of ferricyanide . An explanation of this difference is afforded by the following experimental facts . The product from rosaniline after reduction with zinc becomes capable of being darkened by ferricyanide ; and if leucaniline , instead of rosaniline , be taken , there is obtained a cantharideslike product , which gives red solutions with alkalies , but is darkened by ferricyanide . Furthermore , if a solution of Kolbe and Schmitt 's rosolic acid be darkened with ferricyanide of potassium , and then precipitated by the addition of an acid , there results a colour-acid , which dissolves in alkalies , giving solutions of the exact tint of the rosaniline-product , and , like it , incapable of being deepened by ferricyanide . The interpretation of all this is , that the rosolic acid obtained from carbolic acid by the action of sulphuric and oxalic acid ( Kolbe and Schmitt ) contains more or less leuco-rosolic acid , produced probably by the reducing action of some sulphurous acid . The rosolic acid got from leucaniline also contains more or less leuco-rosolic acid . The rosolic acid obtained from rosaniline is free , or almost free , from leuco-rosolic acid . Be this , however , as it may , there can be no doubt that rosaniline and carbolic acid give essentially the same product when the former is treated with nitrous acid in the manner we have described , and the latter with sulphuric and oxalic acids as in Kolbe and Schmitt 's process . Adopting the " Ethylene type , " we have the following expressions for the reactions of rosaniline : Rosaniline . Azo-rosaniline . N CG II II II N ? 2 N 2C6 113 2 H.O CI NC6 EI , II N O , _ NC H2 NCJLHII +IINO1 , 2N 6C 3 2H,0 N C , IH5 1H +HN 0 , N , C , 11 , 2 H , 0 Rosolic Acid . C N. C( , + 110 OC-I +2Ne H{ C1t1 0 f , 11 2U32 1-12 6 On comparing the formula of rosolic acid given thus by Griess 's process applied to rosaniline , we find that it differs from the formula deduced from Kolbe and Schmitt 's analysis , viz. OC6 I-I5 OCJI , I OC 11 O65 OH by one atom of oxygen . We are inclined to think that this difficulty must be got over by correcting the formula deduced from Kolbe and Schmitt 's research . If the numbers required by the formulae C20 II 0L and C2o II , , O0 be calculated , it will be found that both of them fall sufficiently near the analytical results actually obtained to allow of the deduction of either from the analyses . Taking the latter , viz. C2o IHI 04 , all will become intelligible : Rosolic Acid . Type . Co C0 i , 11 C00 CHH C20 H18 ? l =C1--2 CH5 II H HII I0 -I IThus rosolic acid appears as an ethyl-hydride , and its generation in the Griess process applied to rosaniline is obvious . To the formula 0C115 0 Co HI H which is derived from rosaniline by the straightforward action of nitrous acid and water , we have to add I2 O , and we get 0c I ? I 11 IIo which is , as was said , a possible expression of the analyses of the rosolic acid obtained from carbolic acid . 1866 . ] 213

112618

3701662

On the Chemical and Mineralogical Composition of the Dhurmsalla Meteoric Stone

214

218

Proceedings of the Royal Society of London

Samuel Haughton

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0048

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112618

10.1098/rspl.1866.0048

http://www.jstor.org/stable/112618

Chemistry 2

Geography

Chemistry

II . " On the Chemical and Mineralogical Composition of the Dhurmsalla Meteoric Stone . " By the Rev. SAMUEL HATGHTON , M.D. , F.R.S. , Fellow of Trinity College , Dublin . Received June 6 , 1866 . On the 14th July 1860 , at 2.15 P.M. , a remarkable meteoric stone fell at Dhurmsalla , in the Punjab ; a small specimen of which was forwarded to the Geological Museum of Trinity College , which I have analyzed with the results contained in the following paper . The direction of the motion of the meteorite was ascertained to be from N.N.W. to S.S.E. The cold of the fragments that fell was so intense as to benumb the hands of the coolies who picked them up but who were obliged , in consequence of their coldness , instantly to drop them . The specific gravity of the Trinity College specimen was found as follows : Weight in air ... ... ... ... ... ... ... . . 3335*4 grs. Weight in water ... ... ... ... ... ... ... . 2354 1 , Sp.gr ... ... ... ... ... . . = 3-399 . The stone is grey , close-grained , and splintery in fracture , and presents fewer specks of metallic iron and magnetic pyrites than usual , and was coated with the ordinary black pellicle on its outer side . From 100 grs. acted on with iodine , which dissolved the alloy of iron and nickel , there were obtained , of peroxide of iron 9'85 grs. , and of protoxide of nickel 1 96 gr. The portion insoluble in iodine was next acted on by dilute muriatic acid and evaporated to dryness at 212 ? , then moistened with muriatic acid and filtered , by which process it was divided into a soluble and insoluble portion ; the portion left on the filter was boiled with carbonate of soda , so as to dissolve the free silica , which was found to be 18'95 grs. This was added to the portion originally soluble in muriatic acid , so as to give the following results:grs . Silica ... ... ... ... ... ... 18-95 Alumina ... ... ... 0 14 [ Present originally as Peroxide of iron ... ... . 14 ' 11 . protoxide and proto[ sulphuret of iron . Carbonate of lime ... ... ... ... none Pyrophosphate of magnesia ... . 51'31 Potash and soda chlorides ... 0'30 Platino-chloride of potassium. . 0-20 Oxide of manganese ( Mn3 04). . 0 66 On treating another 100 grs. of the meteorite for sulphur , by boiling in muriatic acid , and conducting th sulphllretted hydrogen into aln ammoniacal solution of sulphate of copper , so as to form a black precipitate of sulphlret of copper , there were foiund by the usual methods 14-8 grs. of sulphate of barytes . There were left , after treatment with ioldine , muriatic acid , and carbonate of so(la , 383 grs. of the 100 grs. originally act ( I upon . From the foregoing facts , we readily obtaini-from treatment with iodine and for sulphurgrs . grls . Peroxide of iron ... ... 9'85 ... . 6-88 iron Protoxide of nickel ... . 1-96 ... . 1 541 nickel Sulphate of barytes ... . 1480 ... . 561 protosulphuret of iron . IHence we find , as the primary analysis of the meteoriteI . Primary Analysis . 1 . Metallic iron ... ... ... ... ... ... ... ... ... ... . . 6-88 2 . Metallic nickel ... ... ... ... ... ... ... ... ... ... . . 1 5.1 3 . Magnetic pyrites ... ... ... ... ... ... ... ... ... ... 56 4 . Earthy mineral ( soluble ) ) ... ... ... ... ... ... ... ... 47(67 5 . Earthy mineral ( insoluble ) ... ... ... ... ... ... ... . 38-30 100'00 The results of the analysis of the soluble portion ( considering that 5( 61 of Fe S is equivalent to 510 of Fe2 O : ) give the following : II . Earthy Mineral ( soluble ) . grs. per cent. Oxygen . 1 . Silica ... ... ... ... 18-95 ... . 39-75 ... . 20637 2 . Alumina0 ... ... ... . 0 19 ... ... 0135 3 . Protoxide of iron ... ... -10 ... . 199 ... . 3768 4 . Protoxide of manganese 0'66 ... . 1'38 ... 0-308 5 . Lime ... ... ... ... . . none ... ... . 6 . Magnesia ... ... ... ... 318 4. . 38 ... 15-374 7 . Potash ... ... ... ... 004 ... . 10 0 001 8 . Soda ... ... ... ... 0 3 ... . 028 ... . 0-071 9 . Loss ... ... ... ... 131 ... . 2-74 ... . 47-67 100()00 40309 Adding together the oxygen of the protoxides , we findRO ... ... ... ... . 19537 Si O ... ... ... ... ... . 0637120i2 ~~Sit)2 . 20637 } 20772 Al,3 . ) . 0'135 J From the preceding result , it is evident that the soluble mineral in this meteorite is chrysolith , or the silicate of magnesia and iron represented by the formula 3 RO , Si O ; in which magnesia preponderates greatly over the iron . The 38'3 grs. of mineral , insoluble in muriatic acid and in carbonate of soda , were now divided into two equal portions , of which one was fluxed with carbonates of soda and potash , and the other with lime and chloride of ammonium-with the following results:grs . Silica ... ... ... ... ... ... ... ... ... ... ... 10-85 Alumina ... ... ... ... ... ... 0-23 Peroxide of iron ... ... ... ... ... ... ... ... . . 2'51 Oxide of manganese ( Mn3 0 ) ... ... ... ... ... . 030 Oxide of chrome ( Cr2 03 ) ... ... ... ... ... ... . . 1'42 Carbonate of lime ... ... ... ... ... ... ... ... . . none Pyrophosphate of magnesia ... ... ... 11 50 Potash and soda chlorides ... ... ... ... ... . . 0'30 Platino-chloride of potassium ... ... ... ... . . 050 Assuming the chrome to be present as chrome-iron , Fe O , Cr2 03 , we find grs. Original weight ... ... ... ... ... ... ... ... ... 19 15 Chrome-iron ... ... ... ... ... ... ... ... ... 2*08 Earthy insoluble ... ... ... ... ... ... ... 17-07 If we now omit the chrome-iron and make the necessary reductions in the foregoing results , we obtainIII . Earthy Mineral ( insoluble . ) grs. per cent. Oxygen . Silica ... ... ... 1085 ... . 63-56 ... . 33-000 Alumina ... ... ... ... 0-23 ... . 1'34 ... . 0'525 Protoxide of iron ... . 1-60 ... . 9-37 ... . 2078 Protoxide of manganese 0-30 ... . 1-75 ... . 0-392 Lime ... ... ... ... . . none ... . Magnesia ... ... . . 4-13 ... . 24-19 ... . 9-666 Soda ... ... ... ... . 008 ... . 047 ... 0119 Potash ... ... ... ... 009 ... . 0-52 ... . 0-087 [ Gain ] ... ... ... ... [ 0-21 ] ... . [ 1-20 ] ... . 17-07 100-00 45-867 The oxygen of the protoxides of the preceding analysis amounts to 12*342 per cent. , but it would be fallacious to form any opinion as to the composition of the whole , so long as we are not acquainted with the constituent minerals that compose it . Collecting together into one view the preceding results , we findIV . Mineralogical Composition of the Dhurmsalla Meteorite . 1 . Nickel-iron ... ... ... ... ... . 82 Nic 68854 Nickel 1-54 2 . Protosulphuret of iron ... ... 5-61 3 . Chrome-iron * ... ... ... ... . . 416 4 . Chrysolith ( peridot or olivine ) 47'67 5 . Minerals insoluble in muriatic acid 34 14 100-00 I shall here add , for the purpose of comparison , the results of my analysis of the meteoric stone that fell at Dundrum , co . Tipperary , at 7 P.M. of the 12th August , 1865 . Dundrum Meteorite . Sp. gr ... ... ... ... 3-066 to 3-570 . I. Mineralogical Composition . 1 . Nickel-iron ... ... ... ... ... .20-60 { In.ickel 195703 2 . Sulphur-iron ... ... ... ... ... . 4-05 3 . Chrome-iron ... ... ... ... ... . 1'50 4 . Chrysolith ... ... ... ... ... . 33-08 5 . Earthy minerals insoluble in muriatic acid ... ... ... ... ... . 40-77 100-00 II . Chemical Composition of the Chrysolith . Silica ... ... ... ... ... . 38-74 ... ... . . 38-86 Alumina ... ... ... ... ... 0-Protoxide of iron ... ... 16-55 ... ... . . 19i74 Protoxide of manganese. . 015 ... ... . . -Lime ... ... ... ... ... 084 ... ... . 072 Magnesia ... ... ... ... 40'93 ... ... . . 36-85 Potash ... ... ... ... . . 0-51 ... ... . . 0-47 Soda ... ... ... ... ... 0-24 ... ... . . 0-22 Loss ... ... ... ... ... . 1 ' 59 ... ..1 ... 3-14 100-00 100-00.4 III . Chemical Composition of the Earthy insoluble Minerals . Silica ... ... ... ... ... ... . . 61'-33 Alumina ... ... ... ... ... ... 1 '72 Protoxide of iron ... ... ... . . 6'06 Protoxide of manganese ... ... 0'78 Limre ... ... ... . 3 ' ! ) ! ) Magnesia ... ... ... ... ... . . 22'02 Soda ... ... ... ... ... ... . . 1-38 l'otash ... ... ... ... ... ... . . 083 Loss ... ... ... ... ... ... ... . 1889 100'00

112619

3701662

On the Preparation of Ethylamine

218

220

Proceedings of the Royal Society of London

J. Alfred Wanklyn|Ernest T. Chapman

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0049

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112619

10.1098/rspl.1866.0049

http://www.jstor.org/stable/112619

Chemistry 2

Chemistry 1

Chemistry

" On the lreparation of Ethylamnine . " By J. ALFRED WANKLYN , and I NEIL'1ST ' T. CIIHAPMAN . Communicated by Dr. FRANKLAND . Received June 8 , 1866 . Iaving recently had occasion to prepare a considerable qulantity of ethylamnile , we have made the observation that this base may be obtained withi rmuch greater facility than is usually believed . We digested together equial volrunes of iodide of ethyl , strong alcohol , iand aqueous anmmonlia . The digestion was carried oii at a very moderate temperaturec , certainly not exceeding 80 ? , but the tubes were constantly agitated . In this manner the reaction is completed in about half an hour . The mixed iodides tiius obtained were evaporated to exipel excess of ammonlia , introduced into a retort ; enough potash was added to neutralize I , of the io(line present , and the mixture was distilled into dlilute hydroclloric acid( . The receiver was thei changed , the samen quantity of Iotash agaill added , and the products collected as before . Then six times as much potash was added , and the products collected . The remaini:lg two-tenths of the potash were added separately . Portions of each of these fractions were converted into p)latinum salts , andi the amount of platinum was determinei d by ignition . Eacl of the first four fir'.ctions corresponding to -t of the total bases obtained , gave more pIlatin:um than corresponds even to pure ethylalmine , and therefore contained ethylamine and am orno ia . Only the last fraction , corresponding to -l , of the enltie bases , gave a lower Iercentage of platinum than corresl)ol(ls to ethylaminle , and tlerefore colltained the dialnd tri-bases . Subjoined are the platilum determinations in this last fraction : I. 0-2133 grin . gave 0-0830 Platinum II . 0-35 ! 0 , , ) 0-1382 or , I. Platinum per clent . 38-91 1 . , , , , , 38'5 Pt Cl. N C , II ; IIl ( C1 contains 39-37 per ceiit . of Pt. l't Cl. N ( ( C , II . , ) , 11 . Cl contains 33542 , , Froml which it will be seen that even the last tenth of the bases did not contain much diand tri-bases . The former a gave , as aforesaid , rather more platinum than ethylamine salt yields , and therefore contained ammonia . In order to make out whether there was any diand tri-base along with the ethylamine il these former fractions , we took No. 3 ( corresponding to ' ; Y ) dm and made a platinum-fractionation as follows : No. 3 gave 40-62 and 40'13 per cent. of platinum . No. 3 , after some pure chloride of ammonium had crystallized out ( the crystals were analyzed and proved to be quite pure chloride of ammonium ) , was converted into a platilum-salt , and that platinum-salt fractionated so as to leave the portion richest in the high bases . This salt , which would be rich in the diand tri-bases if any had been present in No. 3 , gave this result:*7666 grm. gave '3090 grm. of platinum=Pt per cent. 400(3 . From which it is manifest that diand tri-bases were absent . From the foregoing we concluded that all the higher bases were concenltrated in the last fraction , but that ammonia passed over during the whole distillation . The objection might therefore be made that mixtures of ammonia and diand tri-ethylamines would give the same numbers . In or(ler to deprive this objection of its force we made the following experiments . Iodide of ethyl , alcohol , and ammonia were digested as before , and the mixed iodides so obtained distilled from excess of potash , the vapour thus obtained absorbed by dilute sulphuric acid , care being taken that the acid was not in excess . The fluid so obtained was rendered very slightly acid with the same acid , and then evaporated on the water-bath . The sernisolid residue was treated with strong alcohol , and allowed to stand one night . It was then filtered , the filtrate measured , and the amount of sulphuric acid determined in a measured portion . Enough K II O was then added to the alcoholic liquid to liberate -sof the bases present . The potash was added in solution in water . The liquid was then distilled , the distillate being received in dilute hydrochloric acid . A portion of this liquid was then evaporated to dryless and placed over sulphuric acid . Its percentage of chlorine was then determined : ? 3826 of salt gave '6696 Ag Cl ; . 4329 per cent. 1C . 'Theory -13')5 . From these numbers it is obvious that the subs:ance must have been pure ethylamine . It could have contained no ammonia , or at most only minute traces , and therefore the above objection is completely disposed of : A portion of this pure hydrochlorate of ethylamine was then treated with aqueous ammonia il insufficient quanltity to combine with the wliole of the hydrochloric acid Ipesenlt . We distilled this liquid inlto dilute hydr-ochloric acid , evaporated it to dryness , and determined the amount of chlorine present in the residue . The result was:*4528 of salt gave 1 3155 AgC1 ; . ' . 59'94 per cent. C1 . Chloride of ammonium would give 66'33 , , Chloride of ethylamine ... ... . . 43'55 , , From these numbers it appears that ammonia is capable of partially expelling ethylamine from its compounds , and thus we have an explanation of the apparent anomaly of the appearance of ammonia with the ethylamine in the above-described experiments . It appears therefore that pure ethylamine may be readily obtained in the following manner . Equal volumes of iodide of ethyl , strong alcohol and ammonia are to be digested together for about half an hour , at a temperature somewhat below that of boiling water , with continual shaking ; the product of this operation boiled to expel excess of ammonia , and then distilled from potash the distillate being received into dilute sulphuric acid , the ammonia separated by means of alcohol , and the alcoholic solution of the mixed sulphates treated with sufficient potash to liberate about 9of the bases present . On distilling this mixture , pure ethylamine , accompanied with alcohol and water , are the sole products found in the distillate .

112620

3701662

On the Expansion by Heat of Metals and Alloys. [Abstract]

220

222

Proceedings of the Royal Society of London

A. Matthiessen

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112620

http://www.jstor.org/stable/112620

Thermodynamics

Chemistry 2

Thermodynamics

IV . " On the Expansion by Heat of Metals and Alloys . " By A. MATTHIESSEN , F.R.S. Received June 14 , 1866 . ( Abstract . ) In a paper " On the Expansion by Heat of Water and Mercury"* , a method of determining the expansion of bodies is described , by which good results can be obtained with comparatively small quantities of the substances to be experimented with . This method , that of weighing the body in water at different temperatures , has been employed for the present research . The results obtained are given in the following Tables : TABLE I.-Formulke for the Correction of the Cubical Expansion by Heat Cadmium ... ... Zinc ... ... ... Lead ... ... ... . Tin ... ... ... . Silver ... ... . . Copper ... ... . . Gold ... ... ... . Bismuth ... ... Palladium ... ... Antimony ... ... Platinum ... ... of the Metals . Vt-=Vo ( 1 + 10-4 x 08078t+ 10-6 x 0140t2)t . Vt-=V ( 1 + 10-4 x 0-8222t+ 10-6 x 00706t2 ) . V= V0 ( 1 + 10-4 x 08177t+ 10-6 x 0.0222t2 ) . Vt , = V ( 1 10-4 x 0.6100t + 10-6 x 0.0789t2 ) . V , =tVo ( 1 + 10-4 x 0-5426t+ 10-6 x 0.0405t2 ) . Vt=Vo ( 1+ 10-4 x 04463t 10-6 x 0-0555t2 ) . Vt= V ( 1 + 10-4 x 04075+10-6 x 0'0336t2 ) . Vt , =Vo ( 1 + 10-4 x 0-3502t + 10-6 x 0.0446t2 ) . Vt=Vo ( 1 +10-4 x 0.3032t+ 10-6 x 00280t2 ) . Vt=V , ( 1 + 10-4 x0 2770t + 10-6 x 0-0397t " ) . V , =Vo ( 1 + 10-1 x0 2554t+ 10-6 x 0'0104t2 ) . TABLE II.-Formulae for the Correction of the Linear Expansion by Heat of the Metals . Cadmium ... ... L , =Lo ( + 10- ' x 0-2693t+ 10-6 x 00466t2 ) . Zinc ... ... ... . Lt=Lo ( 1 + 10- ' x 0'2741t+ 10-G x 00234t2 ) . Lead ... ... ... . L , ==L ( 1+ 10-1 x 0'2726t+ 10x 0-0074t2 ) . Tin ... ... ... . L=Lo ( + 10-x 02033t + 10- . x 00263 ) . Silver ... ... . . Lt=I= ( l+10- ' x 0'18091t+10-0 x 00135tF ) . Copper ... ... . . L , =Lo ( 1 +1 0x 048 1t + 10x OO185a ) . Gold ... ... ... . LL ( 1 + 10- ' x 01358t + 10X 00112t2 ) . Bismuth ... ... L , = L , ( 1 +10- ' x 0-11 67t + 10-0 x 0-0149t2 ) . Palladium ... ... L= Lo ( 1 + 10- " x.01O lt+ 10-0 x 000932t ) . Antimony ... ... Lt-=L ( 1 + 10- ' x 00923t+ 10-G 001 32t2 ) . Platinum ... ... L , =Lo ( 1+10- ' x 00850t+10-0 x 0-003512 ) . TABLE III.-Formulae for the Correction of the Cubical Expansion by Hleat of the Alloys . Sn , Pb : Vt=Vo ( 1 + 10- ' x 06200t+ 10-I x 0-0988t2 ) . Pb , Sn : V=Vo ( 1 + 10- ' x0 8087t +1 0- ' x 003'32t2 ) . Cd Pb : V=V0 ( 1 + 10-4 x 0'9005t + 10x 0'0133t2 ) . Sn4 Zn V , =V , ( 1 + 10x 0'6377t+ 10x 00807 t12 ) . Sn , Zn V , =V , ( 1 + 10x 0-6236t+ 10-0 x 0-0822f2 ) . Bi , , Sn : V=Vo ( 1 + 10x 0-3793t 10-6 x 0-0271 2 ) . BiSn2 : Vt=Vo ( 1 +10- " x 0-4997tt+ 10-6 X 00101 t2 ) . Bi2 , Pb : Vt=Vo ( 1 + 10- ' x 0-3868t + 10-6 x 0-0218t2 ) . Bi Pb2:Vt=Vo ( 1 +10x 0-84(2t+ 10-6 x 001.59t2 ) . Cu+ Zn ( 71 p. c. Cu ) : V =V , ( + 10-4 x 051611+ 10- " x 00558t2 ) . Au Sn , V-=Vo ( 1 + 10-4 x 0-3944t+ 10x 0-0289t2 ) . Au , Sn7 V , =V0 ( 1 + 10x 041651t+ 10- ? x 0-0263t2 ) . Ag , Au V , =V0 ( 1 . + 10-4 x 05166t ) . Ag Au V , =Vo ( 1 + 1.0-4 x 0491.6 ) . Ag Au , V , = V , ( 1 + 10-4 x 03115 + 10x 0.11851 " ) . Ag + Pt ( 66-6 p. c. Ag ) Vt=V0 ( 1 + 10- " x 0-4246t + 10-6 x 00322t2 ) . A+ Cu ( 66-6 p. c. Au ) Vt=Vo ( 1 + 10x 0-401)51t+ 10- ; x 0(064212 ) . Ag+ Au ( 36 1 p. c. Ag ) V , =V , ( 1 + 10x 0'4884t+ 10- ' ; x 0-0552t2 ) . Ag Au ( 71-6 p. c. Ag ) Vt=V , ( 1 + 1.0x Ol443.t + 10-0 x 0.01301t ) . nlmber of the zerios . I have also preferred keeping the exponents constant , adding , instead of altering them , a zero after the decimal point when required . TABLE IV.-Formulhe for the Correction of the Linear Expansion by IIeat of the Allovs . Sn1 Pb I , t= L , ( 1 + 10-- ' x 0206 ; ( t+-10-G x 0-0329t2 ) . Pb , Sn I , t= Lo ( 1 +10- ' x 0269( ; t+ 10- ' x0 '0111 t2 ) . Cd Pb L , = o ( 1 + 10x 0-3002t+ 10- ' ; x 00044t2 ) . Sn , Zn Lt= , ( 1 +10--l X 0-2126t+0-6 x 002( ; 91t2 ) . Sn , Zn L , = Lo ( 1 . + 10X 0 2079 ? t+1 0x 0-02i74t2 ) . Bi , , Sn L= L , ( 1 10-'x 0 ' 126t10X x 00090t ' ) . Bi Sn12 L= L , ( 1 + 10-l x 0-1 ( ; ( ( )t+ 0-1 x 0.0034t2 ) . Bi , Pb Lt , = Lo ( 1 + 10- ' x 0'1293 + ' 0- ' x0 '007312 ) . Bi Pl , Lt , =L ( 1 + 10- ' x 02821 . ? ? 10- ' ; x.00-:3t2 ) Cu + Zn ( 71 p. c. Cu ) L , = Lo ( 1 + 10- ' x 01 720t+ 10- ' x 0(00()S(2 ) . Au Sn2 L= L , ( 1 + 10x 0-:1151t+ 10x 0(00962 ) . Ag An t= L , , ( 1l + I0 x 01()1(38/ ) . Ag Au . , Lt= L , ( 1 + 10- ' X ( 03St+ 10x 0 )0395 , t ) . Ag+ Pt ( G6*6 p.c. Ag ) Lt= L , ( 1 ? +10- ' x 0:141)+1.0x 00107 2 ) . An ? +Cu ( GG66 p. c. Au ) L , = L , ( 1 + 10x 0I1 'l St+ 10x )00214'2 ) . Ag+Cu ( 36li p.C. Ag ) L , = 1 ( 1 . +10- ' x 01 128t +10- ' ; x 0'12t ' ) . Ag+ Cu ( 71 6 p. c. Ag ) L= Lo ( 1+10x 0x1471t 10- ' X 0 ' 043t2 ) . From the above the following conclusion is drawn-namely , that just as it may be said that the specific gravity of an alloy is approximately equal to the mean specific gravities of the component metals , so also from the foregoing we may deduce that the volume which an alloy will occupy at any tenmperature between 0 ? and 100 ? is approximately equal to the mean of the volumes of the component metals at the same temperature , or , in other words , the cubical or linear coefficients of expansion by heat of a'n alloy between 0 ? and 100 ? are approximately equal to the mean of the cubical or linear coefficients of expansion by heat of the compoonent metals . V. " On the Colouring and Extiaction Matters of the Urinc.-Plart II . " By EDWARD SCIIUNCK , F.R.S. Received June 20 , 1866 . See abstract , anttei ' , p. 1 .

112621

3701662

On the Absorption and Dialytic Separation of Gases by Colloid Septa. [Abstract]

223

224

Proceedings of the Royal Society of London

Thomas Graham

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112621

http://www.jstor.org/stable/112621

Thermodynamics

Chemistry 1

Thermodynamics

VI . " On the Absorption and Dialytic Separation of Gases by Colloid Septa . " By T-OMAS GRAHAM , F.R.S. , Master of the Mint . Received June 20 , 1866 . ( Abstract . ) It appears that a thin film of caoutchouc , such as is furnished by varnished silk or the transparent little balloons of india-rubber , has no porosity , and is really impervious to air as gas . But the same film is capable of liquefying the individual gases of which air is composed , while oxygen and nitrogen , in the liquid form , are capable of penetrating the substance of the membrane ( as ether or naphtha do ) , and may again evaporate into a vacuum and appear as gases . This penetrating power of air becomes more interesting from the fact that the gases are unequally absorbed and condensed by rubber , oxygen 2 ? times more abundantly than nitrogen , and that they penetrate the rubber in the same proportion . IHence the rubberfilm may be used as a dialytic sieve for atmospheric air , and allows very constantly 41'6 per cent. of oxygen to pass through , instead of the 21 per cent. usually present in air . The septum keeps back , in fact , one-half of the nitrogen , and allows the other half to pass through with all the oxygen . This dialysed air rekindles wood burning without flame , and is , in fact , exactly intermediate between air and pure oxygen gas in relation to combustion . One side of the rubber-film must be freely exposed to the atmosphere , and the other side be under the influence of a vacuum at the same time . The vacuum may be established within a bag of varnished silk , or in a little balloon , the sides being prevented from collapsing , by interposing a thickness of felted carpeting between the sides of the varnished cloth , and by filling the balloon with sifted sawdust . For commanding a vacuum in such experiments , the air-exhauster of Dr. I-ermann Sprengel* is admirably adapted . It possesses the advantage that the gas drawn from the vacuum can also be delivered by the instrument into a gas-receiver placed over water or mercury . The " fall-tube " has merely to be bent at the lower end . The surprising penetration of platinum and iron tubes by hydrogen gas , discovered by MM . H. Sainte-Claire Deville and Troost , appears to be connected with a power resident in the same and certain other metals , to liquefy and absorb hydrogen , possibly in its character as a metallic vapour . Platinum , in the form of wire or plate , at a low red heat may take up and hold 3'8 volumes of hydrogen , measured cold ; but it is by palladium that the property in question appears to be possessed in the highest degree . Palladium foil from the hammered metal , condensed so much as 643 times its volume of hydrogen , at a temperature under 100 ? C. The same metal had not the slightest absorbent power for either oxygen or nitrogen . The capacity of fused palladium ( as also of fused platinum ) is considerably reduced ; but foil of fused palladium , for which I am indebted to Mr. G. Matthey , still absorbed 68 volumes of gas . A certain degree of porosity may be admitted to exist in these metals , and to the greatest extent in their hammered condition . It is believed that such metallic pores , and indeed all fine pores , are more accessible to liquids than to gases , and in particular to liquid hydrogen . Hence a peculiar dialytic action may reside in certain metallic septa , like a plate of platinum , enabling them to separate hydrogen from other gases . In the form of sponge , platinum absorbed 1*48 times its volume of hydrogen and palladium 90 volumes . The former of these metals , in the peculiar condition of platinum-black , is already known to take up several hundred volumes of the same gas . The assumed liquefaction of hydrogen in such circumstances appears to be the primary condition of its oxidation at a low temperature . A repellent property possessed by gaseous molecules appears to resist chemical combination , as well as to establish a limit to their power to enter the minuter pores of solid bodies . Carbonic oxide is taken up more largely than hydrogen by soft iron . Such an occlusion of carbonic oxide by iron , at a low red heat , appears to be the first and a necessary step in the process of acieration . The gas appears to abandon half its carbon to the iron , when the temperature is afterwards raised to a considerably higher degree . Silver has a similar relation to oxygen , of which metal the sponge , fritted but not fused , was found to hold in one case so much as 7'49 volumes of oxygen . A plate or wire of the fused metal retains the same property , but much reduced in intensity , as with plates of fused platinum and palladium in their relation to hydrogen .

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Notes on the Rearing of Toenia echinococcus in the Dog, from Hydatids, with Some Observations on the Anatomy of the Adult Worm

224

226

Proceedings of the Royal Society of London

Edward Nettleship

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0052

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112622

10.1098/rspl.1866.0052

http://www.jstor.org/stable/112622

Biology 2

Paleontology

Biology

VII . " Notes on the Rearing of Tacnia echinococcus in the Dog , from Hydatids , with some Observations on the Anatomy of the Adult Worm . " By EDWARD NETTLESHIP , Mem. Royal Agric . Coll. Communicated by T. SPENCER COBBOLD , M.D. Received May 24 , 1866 . On March 28th , 1866 , I obtained from Clare Market the liver and lungs of a sheep containing numerous Echinococcus hydatids ; in some the outer cyst was partly calcified , but all the hydatids contained clear fluid , and great numbers of scolices attached to the endocyst . Within two hours of the death of the sheep to which the organs belonged , I gave two or three of the smaller hydatids to a young dog , about six months old ; first puncturing the hydatid and administering the collapsed cyst , and then making him drink the fluid of the cyst , in which some Echinococci were floating . The next day I gave him a second feeding of the remaining hydatids ; this second batch he threw up within half an hour of the feeding , but he afterwards swallowed the broken membranes again , and did not afterwards vomit . I was careful to administer the hydatids from both calcified and non-calcified cysts . The animal remained perfectly healthy , and became very much fatter ; he was fed for the most part on cooked kitchen refuse , but I cannot be positive that he never obtained any raw food . On May 15th ( the forty-seventh day after the first feeding ) I killed the animal , and examined the intestines . In the first ten inches of bowel below the pylorus there were no Tnenise ; at that distance a single Taenia echinococcus appeared , moving actively ; for the next two or three inches there were none , but at about fourteen inches below the pylorus several more appeared , and immediately after this they became so numerous as to present almost the appearance of distended lacteals ; this continued for about a foot in extent , and then they gradually became less numerous , and ceased at about three feet from the pyloric orifice . There were also four specimens of T. marginata , varying from two to three feet in length , and two of T. cucumerina . The part of the intestine cnttaining T. echinococcus was immediately put into dilute carbolic acid , and the worms not examined until two days subsequently ; after that interval they were still tolerably adherent to the mucous membrane , though a good many had fallen off . On detaching them with needles , or examining those which had fallen off , nearly all were found to be quite destitute of hooks ; but one ( from which the outline sketch , Plate VIII . fig. 1 , was taken ) had a tolerably complete double row ; in this specimen , however , the hooks and proboscis were inverted , while in most specimens the latter part was protruded . In fig. 2 is a single hook of T. echinococcus , probably from the posterior circlet , magnified more highly . Fig. 3 shows at a , a hook of the posterior circlet , and at b , one from the anterior circlet of an Echinococcus-scolex from an ox . There seems very little difference between corresponding hooks of the scolex and of the adult tapeworm , unless the latter be rather stouter and have larger processes . On -lth of a square inch , where the worms were thickest , I counted twenty-five of them ; by calculation there were about twenty-two square inches of intestine covered in this way , allowing for the more thinly scattered parts at each end of the infected part ; this gives a total of 8800 specimens of T. echinococcus in this dog 's bowel . I have examined carefully numerous specimens of these worms with the microscope , with especial reference to the arrangement of the sexual organs ; the great majority are sexually mature , and contain a greater or less number of eggs . It is not easy to make out accurately the arrangement and connexions of the ovary , yelk-forming glands , and uterus , as described by Leuckart* , but fig. 4 gives a tolerably correct representation , in the 3rd ( immature ) segment . At a is the vagina , continued as an indistinct tube to b , which I suppose to be the seminal vesicle ; immediately beyond this is a dark mass ( o ) containing spherical , highly refractive bodies ; this is the ovary . On either side and in front of this are the yelk-forming glands ( e ) , two somewhat indefinite lobular organs apparently communicating with the vagina in front of the seminal vesicle . At c and d are the globular testicles ; f is the rudimentary vas deferens . Running forwards from the vagina is another narrower tube g , which passes quite to the anterior end of the segment , where it becomes at first slightly dilated ( fig. 5 , u ' ) , and afterwards enlarged into the head of the uterus ; a large spherical sac full of ova is readily seen with the naked eye in many sexually mature segments ( fig. 4 , ut . ) . The greater part of the body of this tube also becomes enlarged into the uterus ( u , fig. 5 ) , but I think that the hinder part continues tubular , and probably constitutes the " wide cavity " leading from vagina to uterus , described by Leuckart . In fig. 5 there is some appearance of this tube continued backwards from u ( a , fig. 5 ) , but I cannot follow it to any communication with the vagina ( va . ) . The same is true in this specimen of the ovary ( ov . ) and seminal pouch ( s.p. ) . The vitelligene glands ( e , fig. 4 ) have disappeared in fig. 5 , and the ovary has become less distinct , but the seminal pouch has developed somewhat , while in fig. 6 , taken from a sexually mature segment , the latter organ is still plainer ; the canal of the vagina has elongated , and shows besides the seminal pouch a smaller dilatation ( a , fig. 6 ) nearer the orifice . In none of the mature segments have I been able to make out any communication between the vagina and uterus , either in front of or behind the seminal pouch . Although Dr. Cobbold has succeeded in rearing a variety of tapeworms from their respective larvse , the Tcenia echinococcus has not hitherto been reared in this country . The importance of this creature in its pathological relations , and the desideratum of more information as to its anatomy , have induced me to place the foregoing facts on record . In conducting the investigation I have taken every precaution to prevent the escape and distribution of the ova and their contained proscolices . EXPLANATION OF PLATE.-Fig . 5 . va . Vagina . a. Tube ( ? ) leading from uterus to vagina . ov . Ovarium . t. Testicles . s. p. Seminal pouch . v. d. Vas deferens . u , u ' . Uterus partly developed . c. p. Cirrhus pouch . i : i:ii ? -- ? I , C , " -I . ? - ? ? ? ?--- ? ; ? i:r ? C : ? -- ? ? ? ? ? ?:i / a a/ -1 , ? ? ? ?I ? ;:\ J 'i d " i ` ; ? ? ? ? c:ii ? ? ? ? ' j ! :i -j F1 iI i : j -i. . i- : / 1 ; C ) rC ) C ) 0 C ) C ) N Cs q- , , i_::-( : i ' . i r ? r ? s. i:i ; rjd / i. . ? i r\s ? , i:'Si i ? * ? KK CZQ I.Lr3 * ' 33_ , , a--__.._ . : ? Y ; _1L ? -i . , ? - ? s ` ; ? ? ?--3 ? ' ) p ? . " ? _ ... . : ir..IS ; 'r / ? rL ' c , ? 9 ? / JJL'i - . j :

112623

3701662

Observations on the Ovum of Osseous Fishes. [Abstract]

226

229

Proceedings of the Royal Society of London

W. H. Ransom

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112623

http://www.jstor.org/stable/112623

Biology 3

Nervous System

Biology

VIII . " Observations on the Ovum of Osseous Fishes . " By W. H. RANSOM , M.D. Communicated by Dr. SHABREY . Received June 21 , 1866 . ( Abstract . ) In this paper the author has communicated the details of observations of which the principal results were stated in a short paper published in the Proceedings of the Royal Society in 1854 , and of further researches on the structure and properties of the egg in several species of osseous fishes . The methods employed in determining the functions of the micropyle , and in conducting the various inquiries entered upon are described . The development of the ovarian ovum is traced in two species of Gasterosteus , and the yelk-sac is shown to increase by interstitial growth , and not by apposition of layers on either surface . A minute description of the germinal vesicle and its contents is given , and the germinal spots are shown to be drops of a thick fluid substance , so apt to change their normally round form , and to vacuolate in their interior , that no perfectly indifferent medium was found in which to examine them . The primitive yelk first fbrmed around the germinal vesicle is shown to differ in some of its chemical and physical properties from that of the ripe ovum ; it is solid , and does not consist of two distinguishable portions . On its surface a yelk-sac was found in very early ova , but in the smallest eggs examined it could not be separated . The reactions of a variety of albumen allied to myosin , which the author has found in variable proportions in the yelk of all the fishes , amphibia , and birds which he has examined , are described , the yelk of the salmon being selected for experiment . This substance , to which the name albumen C. is given provisionally , is remarkable , in addition to its being easily precipitable by water in excess , for forming under certain conditions a solution in dilute nitric acid not coagulable by boiling . Some account is rendered of the reactions of an acid compound of phosphoric acid with an organic substance also met with in the yelk of various animals . The phenomena which follow impregnation prior to the commencement of cleavage are described , and are shown to be chiefly due to the influence upon the yelk of water which has passed through the yelk-sac . Some variations which occur in this respect in different species of osseous fishes are described , and the ova of Gasterosteus are shown to be remarkable il having a viscid mucoid covering derived from the oviduct , which prevents the imbibition of water through the yelk-sac , so that it only then enters and forms a breathing-chamber after impregnation , when it passes through the aperture in the apex of the micropyle ; whereas in the eggs of salmon and in those of most other fishes , unimpregnated ova rapidly absorb water by the whole surface of the yelk-sac , the yelk contracting at the same time to form the breathing-chamber . The concentration of the formative yelk , originally forming a thin layer over the whole yelk-ball , at the germinal pole is also proved to be due to the action of water , of which it requires a free supply sufficient to distend the yelk-sac , and to be independent of fecundation . The contractions of the yelk are shown to be also independent of the action of the spermatozoids , and to be reactions following the entrance of water into the breathing-chamber ; and this not only as regards the rhythmic waves , which pass over the surface of the food-yelk , but also the fissile contractility of the formative yelk , by virtue of which it cleaves into irregular and unsymmetrical masses , and which the author conceives to be regulated only by the influence of the seminal particles . The cortical layer of the food-yelk or inner sac , which is shown to resist in a remarkable manner osmosis , is found to be the rhythmically contractile part , although requiring for its manifestation the presence of acid foodyelk upon its inner surface . Evidence is given to show that the contractile property of the yelk of both kinds requires , as an essential condition of its manifestation , the presence of oxygen in the surrounding medium , and that the food-yelk , while the rhythmic waves are passing over it , consumes less than does the formative yelk , while regularly cleaving after fecundation ; also that some product of oxidation is formed during these movements , which itself tends to check them , but which the author failed to determine the nature of . Proofs are also given that a certain moderate rise of temperature increases the activity of these contractions . Experiments are related which show the extreme limits the yelk will bear without destroying them , and the temperature at which commencing chemical change prevents further contraction . The reactions of the substance of the yelk under the stimulus of galvanism are recorded , and evidence afforded that the food-yelk and the cortical layer alone are excited to contraction by it , attempts made to induce fissile or other contractions of the formative yelk resulting in electrolysis of that highly unstable substance . Experiments made to ascertain the effects produced by poisonous substances on the contractions of the yelk are recorded , and the general fact ascertained of the extreme indifference to such agents of yelk protoplasm . Carbonic acid , however , is shown to destroy the contractility rapidly , and chloroform to arrest it for a time . The process of cleavage is described , and experiments are given which show that oxygen in the surrounding medium is an essential condition of its occurrence . The influence of heat in quickening it , and the comparative indifference which it shows to the action of a galvanic current and to most poisons , are proved by a series of experiments , in which also the remarkable and destructive activity of carbonic acid is evidenced . The author has considered the egg as a cell , its contents as a protoplasm , of which the firmer cortical layer is the equivalent of the primordial utricle , and the fluid food-yelk of the liquid contents , while the formative yelk is represented by the granular accumulation around the nucleus . Two stages or grades of development of protoplasm are conceived to be represented by the two forms of yelk , and a parallelism is attempted to be drawn between them and the stages of development through which many amceboid organisms pass , and which the author believes to have a wide , if not a universal existence in the organic world ; the lower grade represented by the homogeneous food-yelk with a cortical layer , and possessed of rhythmic contractility , passing into the higher represented by the formative yelk of a granular structure , and possessed of a fissile contractile property only .

112624

3701662

Variations in Human Myology Observed during the Winter Session of 1865-66 at King's College, London

229

244

Proceedings of the Royal Society of London

John Wood

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0054

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112624

10.1098/rspl.1866.0054

http://www.jstor.org/stable/112624

Anatomy 2

Nervous System

Anatomy

IX . " Variations in Human Myology observed during the Winter Session of 1865-66 at King 's College , London . " By JOHN WOOD , F.R.C.S. , Demonstrator of Anatomy . Communicated by Dr. SHARPEY . Received May 3 , 1866 . In the present paper are given the results of observations , made with the greatest possible accuracy and care , of the muscular anatomy of thirty-four subjects , chiefly of the male sex , with an especial view to the study of the combinations of these abnormalities , and the directions in which they chiefly tend . To enable the reader more readily to comprehend these results , the author has tabulated them in the sheet appended to the paper . In the Table the names of the muscles placed at the head of each column refer to those in which more than one variety has been observed in the session . They will be found to correspond very closely with those given in the former papers by the author . In columns 4 , 21 , and 27 are placed those of which only one example has been met with . Some of these , however , are of much importance . To explain the nature of the abnormality more precisely than could be done in the Table , a word or two will be necessary on such of the specimens as may be considered novel or typical . Four columns are occupied by variations of the head and neck , the examples of which amount in the aggregate to twenty-two ; some of the muscles in these may , however , strictly be considered as muscles also of the upper extremity , especially those in col . 3 , which I have denominated cleido-occipital . Col. 1 . Platysma myoides.-The first of the two varieties noted ( in subject 20 ) was connected with the inner side of the lower end of the normal muscle , the fibres passing in a broad band downwards and inwards , over the origin of the sterno-cleido-mastoid , the clavicle , and upper fibres of the pectoralis major to be inserted into the fascia covering the sternum as far down as the third costal cartilage . The second ( subject 29 ) was connected internally with the sternal fascia between the second and third costal cartilages , and crossing obliquely outwards and downwards over the lower fibres of the pectoralis major and axillary cavity , became attached to the tendon of the latissimus dorsi , exactly as we find its homologue , the panniculus carnosus , to do in the lower animals . This variety of the Platysma does not appear to have been previously recorded . 2 . Digastric.-The two varieties of this muscle were found , as usual , in the anterior belly , which was double . In the first ( No. 1 ) the redundant belly was attached by the median raphb to the one on the other side , and was implanted upon the tendon in the usual manner . The second decussated with its fellow on the opposite side , and each became attached to a part of the digastric fossa on the opposite half of the mandible , as given in the author 's first paper , alud described by Henle and other anatomists . 3 . Cleido-occipital.-The author has ventured to bestow this name upon a muscle which proved , when looked after , to be so common that not less than eleven specimens were found out of the thirty-four subjects . It will be best understood by reference to fig. 7 a , in the subject of which it was found in conjunction with a sternoclavicular muscle . It is placed along the hinder border of the sterno-cleido-mastoideus , usually separated , however , by a distinct areolar interval from both the sternal and clavicular fibres of this muscle . It is attached below to the juinction of the innier and middle thirds of the upper border of the clavicle , and above to the superior curved line of the occipital bone , close to the origin of the trapezius mnisele . It is described by Meckel ( Handbuch der mensch . Anatomy , 1816 , p. 474 ) as an accessory to the sterno-cleido-mastoid sometimes met with . It may be considered as a lateral extenlsion and separation of part of the clavicular fibres of the sterno-cleido-mastoid , which , in the nlormlal arrangement , are crossed and entirely covered at the upper part by the sternal portion , and do not extend at their insertion beyond the mastoid portion of the temporal bone . The author has found that in the Guineapig and some other Rodents it constitutes a separate muscle , entirely distinct from the sterno-mastoid , carrying with it the whole of the clavicular fibres of the sterno-cleido-mastoideus . In the Dog and Cat , and probably in the other Carnivora , it forms part of the long muscle , the cephalo-hIumeral . In these animals the cleido-mastoid is a distinct muscle , joining with the cephalo-humeral at the rudimentary clavicle . In the Hedgehog , on the other hand , the cleido-mastoid is blended with the sterno-mastoid , while the cleido-occipital is placed as a distinct muscle behind it . In the Apes and Monkeys it is always present , but continuous with the hinder border of the true sterno-cleido-mastoid , with a more or less distinct intermuscular space* . The above peculiarities of its comparative anatony , and the fact of its separate attachment to the occipital bone , instead of the mastoid portion of the temporal bone , have induced the author to propose the niame here given to it . 4 . Of the single specimens in this column the levator claviculte was in most respects the counterpart to that given in the author 's last paper ; but it was found only on the left side , arising from the three upper cervical transverse processes in front of the levator anguli scapulte , and inserted into the outer half of the clavicle , behind the anterior fibres of the trapezius . On the opposite side it was not found , but a very distinct cleidooccipital was present . This again was not found on the left side , but appeared to supply the place of the levator claviculca . The costo-fascialis cervicalis , of subject 28 , was in every respect like those described in the author 's two last papers . The sternalis brutorum was a small developmenl t on the right side only , reaching from the third to the sixth costal cartilage . The rest of the muscles in this column scarcely need a more extended description than is there found . No less than seventeen out of the twenty-seven columns denoting the different kinds of variety are occupied by those of the arm , of which there are seventy-one examples . 5 . Epigastric slips of the _pectoralis major presented various degrees of development of the so-called chondro-epitrochlear muscle of the Apes and Monkeys , but reaching only as far as the insertion of the rest of that muscle into the bicipital ridge , and terminating distinctly from it . None of them were so complete in their developmenit as those described in the author 's first paper . One specimen is seen in fig. 1 a , in significant cornbination with the ape-like variation placed in the next column . 6 . The developments of the pectoralis minor given in this column are such as may easily be overlooked , but when closely sought for , as in the last session , have yielded no less than five specimens out of thirty-four subjects . The variety consists in the prolongation of the tendon of insertion as a flat tendinous slip , sometirnes connected with a large portion of the muscular fibres , over the upper surface of the coracoid process , which is grooved distinctly for its reception . This tendon then joins that of the supraspinatus muscle , and blending with it and the capsular ligament , is implanted into the upper facet of the greater tuberosity of the humerus ( see fig. 1 6 ) . In the subject of the sketch ( a female ) aniother tendinous slip was directed upwards and outwards , and lost upon the coraco-acromial ligament . The insertion of the pectoralis minor into the shoulder-joint capsule is mentioned by Meckel ( op . cit. p. 467 ) , giving Gantzer as his authority * . This prolongation of the tendon to the humerus reaches to a greater extent in the Monkeys in proportion to the diminution in size of the coracoid process . In the Carnivora it is entirely inserted into the greater tuberosity , and blends more or less intimately with the pectoralis major . In subject 22 the upward direction of the insertiork of the pectoralis minor becomes more marked as an insertion of the upper muscular fibres into the costo-coracoid membrane and the clavicle itself . The origin of the muscle was in this case higher than usual , reaching to the first intercostal aponeurosis . This upward development of the pectoralis minor is an approximation to the condition of its insertion in the Rodents , and , as the author believes , is a formation identical with the sternoclavicular muscle , and fouind in subject 27 , column 21 ( fig. 7 ) . 7 . In this column are given two opposite tendencies of development of the latissimus dorsi . Of the first are those not uncommon slips of communication between this muscle and the insertion of the pectoralis major , passing in front of the axillary vessels and nerves ( see fig. 1 c ) , described by Meckel , Langer , and Gruber ( Achselbogen ) . The author re* De Souza describes a case in which the whole of the peceoralis minor was inserted into the capsuLle of the shoulder-joint ( Gazette Medicale , 1855 , No. 12 ) . gards these as imperfect developments of the so-called dorsi-epitrochlear muscle of the lower animals . None have been found this session extensively developed , and these only in three subjects , of which the last ( No. 32 ) was one remarkable for the num-lber of its muscular abnormalities . The other varieties found were two specimens of the remarkable offset sent from the latisssimus uipwards towards the coracoid process , which the author described in his paper read two years ago to the Society , urnder the name of the chondro-coracoid muscle . It arises with the upper costal fibres of the latissimus from the ninth and tenth rib-cartilages , asceniding so as to cross the axillary cavity obliquely outwards . In the specimen figured in the author 's first series it was inserted with the.pectoralis minor into the tip of the coracoid process . In subject 10 ( fig. 2 ) it is inserted partly into the lower surface of that process ( a ) , and partly into the capsular ligament of the shoulder with the tendon of the supra spinatus ( b ) . It will be observed to pass between the trunks of the axillary plexus , separating the posterior from the lateral cords . The latter and the vessels are cut to show the musele . In subject 28 this muscle was connected with the origin of the coraco-brachialis , and passed with it to the tip of the coracoid . A similar slip of muiscle , passing from the 5th , 6th , and 7th ribs to the muscles connected with the coracoid process , was observed by Theile ( Jourdan 's Translation , p. 204 ) . In all the specimens the unvarying origini of this curious slip , and its relation to the one which joins with the insertion of the pectoralis major , and to the chondroepitrochlear muscle of the lower animals , show it to be the result of an upward displacement of the same typical structure , ranging from the insertion of the pectoralis major to that of the pectoralis minor . 8 . The increased number of the heads of the biceps in the two subjects in this column were of the more usual kind described by Meckel and others , arising from the fibres of the brachialis anticus and from the greater tuberosity of the humerus . 9 . In subjects 14 and 17 the 6rachialis anticus presented a continuiity of a large portion of its outer fibres of origin into those of the supinator longus , which is not uncommon , althoughi not , as far as the author is aware , previously noted in the humani subject . It is a very common arrangement in the Apes and Monkeys , assisting them very materially in climnbing and twisting the body while hanging by the anterior extremities . In subject 30 there was a brachio-fascialis or quasi-third head of the biceps , simriilar to that described in former papers . On the opposite arm was found a curious fusiform muscle , springing high up from the brachialis anticus , and connected below with the pronator radii teres towards its insertion . 10 . The flexor sublimis digitorum in subjects 5 and 13 gave off on the outer side of its coronoid origin a separate slender tendon , which became the sole origin of a first lumbricalis muscle . In both , another first lumbricalis was given off from the usual place on the indicial tendon of the , pe)forans . In No. 13 also a curious division of the abnormal lumbricahls occurred , into two parts , 'of which the innermost was implanted upon the tendon of the pe^foratus , near its division within the sheath of the index finger ; while the outermost joilned the normal lumbricalis near its usual place of insertion . Higher up in the arm another muscular slip connected the redundant tendon from the su6limis with the indicial tendon of the profundus . In subject 9 was a muscular coninexion of the flexor sublimis with the origin of the flexor longus pollicis , like that described in the last paper . 1 1 . The variations of the flexor _profundus digitorum in three subjects consisted merely in a not uncommon distinct and superficial muscular origin from the coronoid process along with the fibres of the sublimis , such as is frequently met with in the lower animals . In subject 8 was found a tendon connecting the indicial part of the flexor mpofundus with the tendon of the flexor longus pollicis . In subject 20 this arrangement was reversed , the tendon going from the flexor pollicis above to the flexor profundus below . This variety is found in the next column . 12 . In addition to the variety just mentionied the flexor _pollicis longus gives , in subject 2 , a tendon to the first tumbricalis on both sides . 13 . The lumbricatles have been found irregular in three other subjects besides those just mentioned , in which the first was seen to arise from the flexor sublimis and flexor lonagus pollicis . In subject 5 the third lumbricalis on the right arm was bifurcated , one half going to the ulnar side of the middle finger and the other to the radial side of the ring finger . Both sides of the long finger were thus provided with this muscle , an arrangement which was repeated in both the hands of the 22nd subject . On the right arm of the 32nd subject the whole of the third lumbricalis ( see fig. 3 c ) was inserted into the inner side of the long finger , while the fourth was entirely absent . This was also the case with the left arm of subject 5 . 14 . The name at the head of this column-flexor carpi radialis brevis -I have applied to a muscle which is given in fig. 3 a , drawn from subject 32 . This subject was , from the number and character of its varieties , the most remarkable of the whole . In this case the muscle arises from the middle third of the front surface of the radius , between the flexor tongus pollicis above ( d ) and the pronator quadratus ( e ) below . Passing under the annular ligament as a distinict rounded tendon , close to the carpal bones , inside of and parallel with the sheath of the tendon of the flexor carpi radialis ( f ) , it is inserted partly into the os magnum , but chiefly into the base of the middle metacarpal bone , where it gave attachment to some fibres of the fexor brevis pollicis muiscle . It is evidently a flexor of the third metacarpal bone , corresponding to the flexor carpi radialis of the second metacarpal . During the last session a precisely similar muscle was described by Dr. Nortoni , of St. Mary 's Hospital , and exhibited by him at a meeting of the Zoological Society . The subject of figure 3 is further remarkable for a distinct slip of tendon from the flexor carpi utnaris ( y ) to the base of the fourth metacarpal bone ( seen at b ) . In this arm we have , therefore , a flexor for each of tne metacarpal bones , reckoning the opponens as one . But further than this , the outer fibres of the extensor ossis metacarpi pollicis in the same arm ( see fig. 6 c ) are separated from the rest by a cellular interval , and arise partly from the fascia covering the radial extensors and supinator longus . They are connected with a distinct tendon , which is implanted into the front part of the outer border of the base of the first metacarpal bone . Traction upon this tendon showed that its action was rather of the nature of flexion with abduction than of extension . This peculiarity of origin is noticed by Henle ( Muskellehre ) . The arm from which figs. 3 and 6 were taken is now in the custody of the Curator of the Hunterian Museum . In fig. 3 is seen also the abnormal insertion of the third lumbricalis ( c ) , the absence of the fourth , and at h the first palmar interosseus of the thumb , described by Henle . In fig. 6 the additional special extensors of the third and fourth fingers are given . In subjects 13 and 31 were found muscles which are entirely homologous with the flexor carpi radialis brevis just described . They had exactly similar origins , were of the same shape and with like tendons , but were iniserted into the inner side of the base of the second instead of the third metacarpal bones , one of them passing , with the tendon of the fexor carpi radialis , through the groove in the trapezium and annular ligament , but the other goinrg outside of that sheath . In subject 6 was found a large fusiform muscle , having its origin from the radius outside of that of the flexor longus pollicis , and reaching as high up as the oblique line below the flexor sublimis . Ending in a distinct , strong , and rounded tendon , it was implanted into that deeper portion of the annular ligament which separates the groove for the flexor carpi r adialis tendon , and with this into the trapezoid , magnum , and base of the middle metacarpal bones . A muscle precisely similar to this was described by the author in his last paper ( subject 1 ) . Its resemblance in appearance , position , connexions , and influence upon the carpus , have induced him to class it with the foregoing flexor carpi radialis brevis as a variation of the same type of muscle , the flexor of the middle metacarpal bone . 15 . The variations of the radial extensors found in this column are of two kinids , which appear to be closely allied . The first kind mentioned are the interchanging muscles frequently seen and recorded by anatomists . These , arising with one of the twin muscles , pass as distinct tendons over to the other , and become inserted with it . Of these , three were found . In the absence of a name the author has ventured to distinguish this form of muscle by that of the extensor carpi radialis intermedius . Of the other kind is found only one example . It is the extensor carpi radialis accessorius first recorded , named and described by the author in his former papers* . It has been chosen as the subject of fig. 4 , taken from the right arm of subject No. 23 , because of its coexistence with the intermediate form of the radial extensors , which was not the case in any of the specimenis before found . It arises from the condyloid ridge of the humerus , below the extensor carpi radialis longior ( f ) , lies between that muscle and the extensor intermedius ( c ) , which separates it from the extensor carpi radialis brevior ( d ) . It has a distinct tendon of considerable size , which , crossing that of the longior , goes through the sheath of the extensors of the metacarpus and first phalanx of the thumb , and divides into two slips , one to be implanited into the base of the first metacarpal , and the other to give part origin to a double abductor jpollicis ( b ) . The tendon of the intermedius ( c ) can be seen to be implanted upon the second metacarpal with that of the longior . In the left arm of the same suibject only the intermediate form was found . The close relation of these two forms is well seen in the figure . The accessorius has an origin somewhat similar to the intermedius , while its insertion and connexion with the short abductor is precisely similar to that often found in the tendon of extensor ossis metacarpi pollicis , with which the radial extensors have usually so close a connexion at its origin , as before alluded to in describing the redundancy of that muscle in subject 32 ( fig. 6 c ) . If we suppose the germ of an extensor intermedius to become blended with that of the upper and outer portion of a double extensor ossis metacarpi pollicis , the result would be the extensor accessorius here described * . 16 . The extensor ca ? pi ulnaris in two subjects sent , in both arms , tendinous slips to the little finger , which were blended with the common extensor aponeurosis ( fig. 5 a ) . This variety is mentioned by Meckel . Henle conisiders it as homologous with that of the peroneus quinti in the foot . In both subjects the arrangement of the slip was strikingly similar to that of the last-named abnormality , but in neither of them was the peroneus quinti found in the foot . In the same arms the extensor minimi digiti ( b ) was found provided with two tendons , both inserted , with a slip from the common extensor , into the dorsal aponeurosis of the fifth digit ( c ) . 17 . In three other subjects , besides the two last mentioned , the extensor miniani digiti was found to have a double tendon . In one the muscle also was doubled . In subjects 5 and 32 the outermost of the tendons of this double muscle was inserted into the extensor aponeurosis of the ringfinger , thus forming a special extensor of this digit ( fig. 6 a ) , joining , before reaching it , with a slip from the common extensor , which directly afterwards again left it , carrying some of its fibres to join the little finger . This arrangement was described by the author in his first paper , and has been also noticed by Vesalius , Meckel , and Hallett in Man , and by Church in the Apes . 18 . In this column are found two specimens of that differentiationof the extensor indicis m'nuscle which results in a proper extensor of the middlefinger . In fig. 6 ( taken from the extensor aspect of the same arm as fig. 3 , subject 32 ) is seen a complete double set of extensor tendons for each of the five digits , in addition to the interesting varieties found on the flexor side ( including a whole set of flexors for the fivemetacarpal bones ) , and in other parts of the body . It was not found in the left arm . In subject 13 , the extensor medii digiti was found in both arms , and , what is significant , it was associated in both with the fexor ca'pi 'adialis brevis before described , showing a special tendency to development of the muscles of the middle digit . A similar tendency is shown in subject 15 , by a duplication of the tendon of the indicator , both tendons in tnis case being inserted inlto the first digit . 19 . Of the extensor brevis digitorutm manus , described in the author 's last papers , fewer examples than usual have been found , none of them very complete . In subject.32 a single slip to the middle finger is founid associated with theproper extensor and aflexor of the metacarpal bone of that digit ; a combination which was present also in the rernarkable subject ( 1 ) described in the last paper , and , with the exceptionl of the proper extensor , in one other subject last session . It may be taken as a further proof of the specializing ten-cdency in the middle finger in this subject . 20 . Of the interossei , five specimens of differeltiation are nioted , chiefly belonging to the first , or abductor inclicis . Two specimens of a palmar interosseus of the thumb are found in Nos. 5 and 32 , both presenting numerous other variations . 21 . Among the miscellaneous muscles of the armi the most noteworthy specimen is that of a sternoclavicuzlar muscle , similar to that described by Haller , and more recently by Mr. Berkeley Hill . This muscle ( given in fig. 7 c , from subject 27 ) arises by a thin tendon from the front of the manubrium sterni , just below the origini of the sterno-mastoid . Spreading as a muscular layer upwards and outwards under the clavicular fibres of the pectoralis major ( b 6 ' , cut and turned up in the figure ) , it is inserted into the lower border of the clavicle , just in front of the subelavius muscle , from which it is separated by the costo-coracoid miembrane ( a ) , extending nearly as far outwards as the origin of the dleitoid . This muscle has been found in Birds , Bats , and Moles . The author has also found it remarkably well-developed in the Guineapig and some others of the Rodentia . HIe believes it to be closely allied to the upward extension of the pectoralis minor , before alluded to , and to result from a differentiation of such an upward extension . In the subject of the sketch it was associated with a cleido-occipital ( a ) , and with an increase in the number of tendons to the little fing , er . In subject 26 was a curious muscular slip extending behinid the axillarv vessels and nerves , from the insertion of the subscapular muscle to the fascia covering the long head of the triceps , and derived from the tendoln of the latissimus dorsi . Apparently this is an imperfect form of development of a short coraco-brachialis muscle , such as that described in a former paper . In subject 13 was a high fascial origin of the abductor minimi diyiti , from the lower third of the forearm , like that described and figured in the author 's first series . This has been observed by Gulnther ( Chirurgische Muskellehre , Taf . xx . Fig. V. 18 ) . A double abductor pollicis brevis was found in three cases , besides that in which it was connected with a slip from the extensor carpi r adialis accessorius ( given in fig. 4 ) . In subject 23 , and also in 32 , was a double extensor ossis metacarpipollicis , the tendon of one being inserted entirely into the annular ligament and origin of the abductor pollicis . The rest of this column scarcely lneeds further description . The six remaining columns are occupied by abnormalities of the muscles of the leg , of which there are thirty-nine examples . 22 . Peroneus tertius.-Two out of five anomalies in this column result from the total absence of this characteristically humani muscle , giving a very ape-like appearance to the foot . In No. 7 it was absent on the right side only ( see fig. 8 ) , in No. 16 on both sides . In subjects 11 and 32 a distinct tendinous slip from it was implanted into the base of the fourth metatarsal . In another , the tendonl was doubled , though both were inserted into the fifth metatarsal , spreading towards the fourth . 23 . Peroneus quinti . In three out of five specimens foutnd , this tendinous slip from the peroneus brevis to the extensor aponeurosis of the little toe was perfect , as described and figured in the last paper . In the remaining two , the tendinous slip from the brevis , instead of reaching the toe , became implanted upon the upper border of its metatarsal bone , near the front end ( fig. 8 a ) . In both cases this slip supplied the place of the peroneus tertius , which was totally wanting , except in the left foot of subject 7 , in which both the slip and the muscle was present , though small . In the subject of the figure the peroneus brevis tendorn gives also a slip of origin to a bundle of muscular fibres which joiln the abductor minimi digiti as a separate muscle ( b ) on the outer side . This is a somewhat similar arrangement to that of a specimen given in the author 's first series , in which the peronetus quinti was provided with a separate muscular belly on the outer border of the foot . tOL . X , 24 . The extensor longus primi internodii hiallucis , described in the author 's first paper , was found in no less than ten out of the thirty-four subjects , in all , except one , in both legs . In seven the muscles and tendons were fully developed and distinct from the fibres of the extensor proprius hallucis , generally arising above , but sometimes below this muscle . In the remaining three ( Nos. 11 , 19 , and 21 ) the abnormal muscle was represented by a tendon given from the extensor proprius near the ankle . In subject 21 this tendon was also , on the right side , contributed to by one from the extensor longus digitorunm . In all the tendon was attached to the base of the first phalanx of the great toe , close to the joint , either distinct from or in union with that from the extensor brevis di.gitorum pedis . 25 . Flexor longus accessorius.-The high origin of this muscle , by an additional head from the lower third of the fibula , or from the fascia covering the flexor longus hallucis , has been observed in three cases . In all it was provided with a distinct tendon , which joinied separately in the union of the long flexor tendlons in the middle of the sole . In subject 26 the flexor accessorius was made up of four distinct heads . 1 . The long head as above described ; 2 , another tapering fleshy belly from the upper part of the os calcis and insertion of the plantaris tendon , in front of the tendo Achillis , and ending in a distinct tendon ; 3 , the usual " massa carnea " from the hollow surface of the os calcis ; and 4 , the outer tendinous slip from the lonig plantar ligament . These all uniting , joined with a large slip from the tenidonr of the flexor longus pollicis , to form a distinct deep or third set of flexor tendons passing to the four outer toes . Each of these joiined that of the _pe forans in the inside of the sheath , about the first joint . 26 . Abductor ossis metatarsi quinti.-This muscle , as described and fig , ured by the author in former papers , was found only in sev-en subjects this session , in all in both feet . This is much less than the proportion found last session . In two out of the five females dissected , they were found well developed , of a fusiform shape , arising from the outer tubercle of the os calcis , and inserted by a distiniet rounded tendon into the base of the fifth metacarpal bone . In five males only , out of the twentynine dissected , were they found as muscles distinct from the fibres of the a6ductor minimi digiti . In the previous session the proportion of female subjects to males was very much greater than in the last . The specimens of this muscle found were also much more numerous , so much so as to be estimated by the author at nearly half the number of subjects . Whether this remarkable difference depends upon the sex , or is accidental , must be decided by future observations . 27 . In the miscellaneous column we have nine single speciinens , as compared with eleveni or twelve in the arms , and six or seven in the head and neck . In a female ( 31 ) was an areolar separation of the front fibres of the gluteus minimus forming a scansorius muscle , like that described in a former paper . In subject 30 the peforatus tendon of the little toe was derived from the fexor accessorius , as seen also last session . In subject 7 , the same tendon is derived from the fifth tendon of the pe ? :forans , as found in the Apes and Monkeys . The two last appear to be , respectively , the imperfect or transitional , and the complete stages of this significant change . Two varieties , which I have not found ' recorded by any anatomical writer , were noticed in subjects 12 and 26 . In the former the abductor hallucis , and in the latter the flexor brevis hallucis sent a considerable muscular slip to the base of the first phalanx of the second toe . In the former the slip passed deeper than the transversuspedis muscle , and in the latter superficial to it . In subject 25 the third lu ? nbricalis took origin from the tendoni of the pe ? foratus instead of the pe ? forans , presenting an analogue to the origin of the first lumbricalis in the hand from a tenidon of the flexor sztblimis pe ? foratus in subjects . S ) and 13 . In subject 2 the fourthl plantar interosseuts arose f om na slip of the tendoll of the 2er oneus lotgucs , as in the instance descr ibed and figuired in the author 's last paper . In subject 16 was a cuir'ious double origin of the tdducetor 7ongusfenmoris , the abnormal hea(l arising with the fibres of the pectinels . In reference to the comnlbina(tionls of the above muscular variations an inspection of the Table will show the following points:-First , that only in two subjects out of the thirty-fouir examined were nto muscular abniormalities found ; i. e. nio deviations from the ordinalry type sufficiently striking to be recorded . It is , indeed , hiighly probable that variabilities of every kinid arc limited only by the possibilities of the permutations and combinations of the Wholc of the structuires of the humnan bodvr . It will be observed also that the grent majority of the abnormalities welC s. ? n ? etricwa , or fouInd on both sides . , Secondclq , that of the total number of muscular variations , 132 ( not reckoning both sides when alike ) , 71 , or more than one half , are found in the arms . If we reckon with these those muscles which , thontgli founlid in the nieck , act ehiefly upon the clavicle , a boon of the upper extremity , viz. the cleido-occipitael and the levatorv clavictlae , Xwe shall have 12 more to add to the 71 , increasing the proportioni of the arm muscles , and diminishing those proper to the head and neck to 10 . The number of abniormalities in the legs amount to 39 , or rather more than half the number of those in the arms ; while in the abdomen and lower part of the trunk not onIe is recorded , though , of course , some may have escaped observation . Thicrdly . The greatest number of abnormalities combined in the same individual is 14 ( in subject 32 ) , a very muscular male , in whom the proportions are 10 in the muscles of the arms ( including the cleido-occi ital ) 3 in those of the legs , and 1 only in the hcad and neck . The similarity betweeni this subject and No. 1 of the last year 's paper is remarkable . In the latter the number of departures from the ordinary type was 16 , of x which all except 7 were found in the arms ( including the levator claviculce ) , 5 in the legs , and 2 in the bead and neck . With the exception of the levator claviculce , costo-fascialis , and supra-costalis , found in the last-mentioned subject , but not in No. 32 , the correspondence ( especially in the arms ) between the different linwes of abnormal departure also is sufficiently close to become significanit , as the reader will have gathered in going through the preceding , pages . In subject 4 of the Table , which presented the only specimen of the levator claviculce founid this session , oiily one other abnormality was found , viz. the abductor of the fifth mnetatarsal bone . This was also founid associated with it in last year 's subject , which presents otherwise a marked colntrast in the niuimber of its abnormalities . In Nos. a and 7 , the one a male and the other a female , there are nine variations respectively , of which , in No. 5 , there is but one which is not in the arm ; and in No. 7 , four in the legs and three in the arms . In No. 2 are eight abniormalities , of which six are in the arms and the rest in the legs . In No. 26 are found seven , of which three are in muscles belonging to the upper extremity , and four in the legs . In No. 13 are six , all in the arms . In thirteen subjects none were found in the legs ; and in four they were found in the legs only , to the extent , in one case , of four examples ; and in all four subjects highly characteristic . None were found in the head , neck , or trunk only* . The extent of correspondence in combination of varieties in the subjects arranged in theTable(taken in the horizontal lines ) cannotbesaid to be striking . The variations seem to crop out here and there withouit much reference to each other . This may , however , be partly owing to the comparatively small number reviewed , and we should scarcely be safe indrawing deductions from it before a much greater number of subjects are treated in a similar way . The correspondence seems to be the greatest in the arm and hand , which here also assume a prominence over the rest of the frame . This , however , may be due to the ereater number of instances found in the upper extremity . The figures which are placed at the end of each line in the Table refer to the number of varieties recorded in each entire subject . Those at the bottom of each column refer to the number of each variety of niuscular abnorrnality . EXPLANATION Of the Abbreviations and References in the Table . R. Indicates the right side of the body on which the abnormality was found . L. Indicates the left side of the body on which the abnormality was found . 'B . Inldicates both sides of the body oI which the abnormality was found . a. Detached muscular slip from 6th cartilage , with separate insertion into humlerus . Also in No. 5 . b. Muscular slip from latissim^-us dorsi to insertion of pectoralis mno , jor . Also in Nos. 5 and 32 . c. Tendon from flexor longus pollicis , giving origin to first lumbricalis . d. Single muscle with two tendons , both inserted inlto little finger . Also in Nos. 9 , 25 , and 27 . e. 14almnaris longus , with belly of muscle below instead of above . f. Fourth plantar interossetes arising from tendon of peroneus longus . fq . Extensor carpi radialis internmcdi4us arising ( muscular ) with lonigior , and inlser ted tendinous with brevior , or vice ver sd . Also in No. a , and the right side of No. 21 . A. Pectoralis minor , giving tendinous slip to greater tuberosity of humerus ; joilling with the tendon of sulpraspinatus and capsular ligament . i. ( Riglit side ) third izmbricalis bifurcated to opposed sides of middle and ring-flngcr . ( Left side ) no lumbricalis to little finger . Also seen in No. 22 . j. Extensor minimii digiti gave a teindoni to the ring-finger on both sides . Also in No. 32 . k > . A first palnar interosseous ( of ilenlo ) , under flexor brevis to pollex . 1 . Flexor carpi radialis brevis , vel profundus , as a , ftisiform muscle , arising from the oblique line of radius , and inserted into the annular ligament . us . DouLble anterior belly of digastric , decussating across the median line . ni . Muscular slip from complexus to r-ectus capitis posticues olqjor . o. Detached miiuscular slip from epitrochlea to olecranoil over ulnar nerve . Ip . Tendinous slip from peroneus brevis to uipper border of fifth metatarsal . q. Flexor longus accessorius nuscularl head arose from deep fascia covering flexor longus digiti . r. Perforatus tendon of fifth toe arose from tendon of perforans . s. Double stylo-pkharyngeus , one behind the other . t. Detached slip of pectoralis inajor , arising from abdominal tendon at epigastriuln , and inserted separately into tendon at humerus . Also in Nos. 9 and 32 . 2c . Tendinous slip prolonged from extensor caspi ulnaris to extensor tendon of little finger . Also seen in No. 27 . V. Detached slip from latissimus dorsi a.t ninth rib , to coracoid process at insertion of pectoralis minor ( chsondro-coracoid ) . wo . Extensor longus primi ineernodii hallucis , arising from fibula and interosseous ligament above extensor proprius hallucis . Also in Nos. 18 , 24 , 25 , 26 , and 30..x . Tendinous slip of insertion of peroneus tertius to base of fourth metatarsal , as well as its usual insertion into the fifth . Also in No. 32 . y. Exteensor longus_prini internodii hallucis tenidon given off from that of extenlsor _proprius hallucis . Also in Nos. 19 and 21 . z. Abductor hallucis sent a large slip to base of first phalanx of second toe . a ' . Muscular slip from coronoid process to flexor profundus digitorum . Also in the two next notices in the same column . b ' . A distinct and separate extensor of the middle digit : in the next notice in the same column the indicator had two tenidolns , both inserted into the forefinger , High origini of abductor minimi digiti from fascita of forearm . d7 ' . Muscular slip connecting the brachialis aenficzts with the.supineior lo ? guse . Also in the next notice in the same columni . c ' . Suvperficial slip connecting the two portions of flexor brevis Ipoliicis . ' . Origin of stylo-glosstus fromii the angle of the lower jaw . g ' . Subcutaneous slip from sternal fascia to cervical fascia . h ' . Musculo-tendinous slip from flexor pollicis 1i2oGus to inclicial portion of profundu . i ' . Flexor car:pi radialis accessorius , a separate muscle connected with tho origin of longior , to be inserted into the base of the metacarpal of 2ollex , giving a slip to abductor pollicis . k ' . Slip of pectoralis minor inserted into costo-coracoid membrane and clavicle . 1 ' . Double muscle , the lower inserted into annular ligament and origin of abductor pollicis & in ' . Flexor lonzgus halluscis exchanged slips with flexor longus dligitorze7n . n ' . Third lusnbricelis arose from ftlxor perforatus instead of p)erforans . o ' . Flexor brevis hallucis sent a largo slip to base of first pha.lanx of second toe . p ' . MIIscular slip from insertion of subscapularis to the n.leck of the humerius and tendon of ltcdissimus , an imperfect coraco-bi rehiclis brevis . q ' . A distinct muscle from front ; of maniubrium to lower border of clavicle , under -fibres of p)ectoralis mqcaor ( Sterno-claviculai- ) . Subelavius also present . r ' . Distinct muscle arising from first rib with sterno-thyroid , and insert ; ed into cervical fascia under sterno-cleido-mastoid ( costo-fcasci(elis cervicalis ) . s ' . Muscular slip from latissimvus dorsi to join coraco-brachialis just below coracoid process , across the vessels of the axilla . t ' . On the left side a miiuscular slip from brachiialis anticus to the fascia of the forearm ; on the right side ai . fusiform muscle forming a high origin of thepronator rad . teres , it ' . Perforatus tendon of little toe from flexor accessorius . e ' . Muscular slip from sp lenius colli to serratus m ; 9agnus . w ' . Thircl lumbricalis to inner side of middle finger . Fourth absent altogether . ' . First dorsal interosseus double . Also in 27 . y ' . Tendinous slip from ftexor carpi utnaris to base of fourth , as well as the fifth metacarpal x ' . Separationof anterior fibres of gluteus minimzes , forming distinct muscle .

112625

3701662

On the Muscular Arrangements of the Bladder and Prostate, and the Manner in Which the Ureters and Urethra Are closed. [Abstract]

244

249

Proceedings of the Royal Society of London

James Bell Pettigrew

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112625

http://www.jstor.org/stable/112625

Neurology

Biology 2

Neurology

X. " On the Muscular Arrangements of the Bladder and Prostate , and the manner in which the Ureters and Urethra are closed . " By JAMES BELL PETTIGREW , M.D. Edin . , Assistant in the Museum of the Royal College of Surgeons of England . Communicated by Dr. SHARPEY , Received June 21 , 1866 . ( Abstract . ) The present communication , which is based on an extensive series of dissections* and illustrated by photographs , is intended to show that the muscular fibres of the bladder , contrary to the received opinion , are spiral fibres , and with few exceptions form figure-of-8 loops . The loops are variously shaped , according as they are superficial or deep , the more superficial loops being attenuated or drawn out so as to resemble longitudinal or vertical fibres , the deeper ones being flattened from above downwards , and resembling circular fibres . These loops are directed towards the apex and base , and are arranged in four sets ; an anterior and a posterior set which are largely developed , and a right and left lateral set which are accessory and less fully developed . The bladder is consequently bilaterally symmetrical . The superficialloops are confined principally to the anterior , posterior or lateral aspects , but the deeper ones radiate and expand towards the apex and base , so that they come to embrace the entire circumference of the bladder in these directions . The expansion of the fibres is greatest towards the apex , and the aggregation of the terminal loops of the anterior and posterior fibres at the cervix ( assisted by the lateral fibres ) form a wellmarked sphincter vesicae in this situation . The fibres pursue definite but varying courses , those which are longitudinal or vertical at one point becoming slightly oblique at a second , oblique at a third , and very oblique or transverse at a fourth . The fibres consequently change their direction and position on the vesical parietes gradually and according to a fixed principle . The principle involved is readily explained . The most external and most internal fibres are always the most vertical and most feebly developed ; those which succeed or follow becoming more and more oblique and stronger and stronger . The fibres from this circumstance are divisible into two orders , viz. , an external and an internal , and these , as has been stated , are grouped in two principal and two subsidiary sets . The two principal sets occur on the anterior and posterior aspects of the viscus , and are so arranged that the terminal or transverse portions of the anterior set intersect the more vertical portions of the posterior set nearly at right angles and the reverse . Similar remarks apply to the subsidiary sets . Between what may be called the vertical or longitudinal and the circular or transverse fibres , other fibres having different degrees of obliquity occur . These consist for the most part of the deeper anterior and posterior spiral fibres , and of the subsidiary spiral fibres from the sides . There is consequently no part of the vesical parietes in which longitudinal , slightly oblique , oblique , and very oblique external and internal fibres may not be found . The additional strength ; secured by this arrangement cannot well be estimated . The external and internal fibres are similarly disposed on the anterior , posterior , and lateral aspects , and if the dissection be conducted from without inwards , the fibres first removed are the mesial , vertical , or longitudinal fibres ; then the slightly oblique fibres inclined on either side , and crossing at acute angles as in an attenuated figure of 8 ; then the oblique fibres , crossing at wider vertical angles as in the more perfect figure of 8 . Lastly , the very oblique fibres , crossing at such obtuse angles as to have been , up to the present , regarded as circular fibres . The fibres which are still deeper and which constitute the proper internal fibres , have a precisely similar , arrangement , but are rudimentary , and consequently not so readily traced . The external and internal fibres , as will be seen from this description , be1866.3 245 come more and more oblique , both from without and from within , or in proportion as the centre of the vesical parietes is reached , the deepest or most oblique external and internal sets forming , by the blending of their terminal or transverse portions , what is commonly known as the central layer . The most external or superficial fibres are connected directly and indirectly with the slightly oblique external fibres , the slightly oblique with the oblique , and the oblique with the very oblique . The very oblique external fibres , on the other hand , are connected with the oblique internal , these in their turn being connected with the slightly oblique internal , and the slightly oblique internal with the longitudinal or vertical internal . In some instances the longitudinal external are connected directly with the longitudinal internal , and so of the slightly oblique , oblique , and very oblique external and internal fibres . The apex and base of the bladder are similarly constructed , and resemble in their general configuration the other portions of the vesical walls ; i. e. , they are composed of longitudinal or vertical , slightly oblique , oblique , and very oblique or circular fibres which cross in given directions on the external and internal surfaces . The four sets of longitudinal or vertical fibres have a crucial arrangement at the apex and base , and the slightly oblique fibres are drawn together at the urachus and cervix by the constrictions which in the embryo separate the bladder from the allantois and urethra . The slightly oblique fibres consequently converge towards the apex and base respectively ; and this arrangement at the cervix greatly assists in closing the urethra , as the fibres naturally come together to form an impervious fiunnel-shaped projection which is directed downwards and forwards . The closure of the urethra is completed by the contraction of the very oblique or circular fibres forming the sphincter , and by the prominence of the uvula vesicee ( luette vesicale ) and median ridge in the female , and the caput gallinaginis or verumontanum in the male . The longitudinal or vertical , slightly oblique , oblique , and very oblique external and internal fibres at the base are continued forward within the prostate to the membranous portion of the urethra , and the external and internal surfaces of the corpus spongiosum . The coats of the urethra are therefore to be regarded as the proper continuation of the walls of the bladder in an anterior direction . The longitudinal or vertical , slightly oblique , oblique , and very oblique spiral fibres which form the tunics of the bladder and urethra are curiously enough repeated in the prostate of the male , and the analogous structure n the female , so that this gland would seem to be composed chiefly of fibrous offsets from the fibres in question . The relations existing between the prostate , urethra , and cervix of the bladder are best seen when vertical , horizontal , and antero-posterior or transverse sections of the bladder and prostate are made . In such sections the external longitudinal or vertical anterior , posterior , and lateral fibres are seen to pass forward on the external surface of the 246 urethra ; a certain proportion passing outwards to be inserted into the anterior , posterior , and lateral surfaces of the capsule of the prostate , others passing inwards or through the gland in a vertical or longitudinal and likewise in a horizontal or transverse direction . The crucial arrangement of the four sets of external fibres at the apex and base is thus clearly traceable in the prostate . Such of the external fibres as are not inserted into the capsule of the prostate are attached to the posterior surface of the pubis , the internal border of the aponeurosis of the levator any , and the fascia covering Guthrie 's muscle . The external fibres investing the dorsal , ventral , and lateral aspects of the urethra and prostate are separated by a considerable interval , thus showing that , although the relations existing between the urethra and prostate are of the most intimate description , they may nevertheless be regarded as independent . What has been said of the external longitudinal fibres applies equally to the slightly oblique , oblique , and very oblique external and internal ones , these bifurcating and distributing themselves with considerable regularity to the walls of the urethra , and the substance of the prostate respectively . The urethra and prostate are thus composed of fibres crossing in every direction as in the bladder itself . The very oblique external and internal fibres are interesting because of the very obtuse angles at which they intersect , and because they are principally concerned in forming the sphincter of the bladder , and the so-called circular layer of the prostate . The very oblique fibres , like the other fibres described , are arranged in an anterior and a posterior set , which are largely developed , and a right and left lateral set , which are developed less feebly . The anterior fibres , which are directed posteriorly , form the posterior half of the sphincter vesicee , and the posterior fibres , which have an opposite direction , the anterior . The sphincter is thus bilaterally symmetrical , and is somewhat oval in shape , the long axis being directed transversely , or from side to side . The two sets of lateral fibres , which also enter into the formation of the sphincter , intersect the angles formed by the crossing of the anterior and posterior fibres , and render its aperture more circular than it would otherwise be . This circumstance , taken in connexion with the fact that the fibres pursue a very oblique direction , has given rise to the belief that the fibres of the splhincter and neck of the bladder generally are circular fibres , which , as the author shows , is not the case . The fibres of the sphincter are best seen by inverting the bladder and dissecting from within , or by making transverse sections of the prostatic portion of the urethra in the direction of the fundus . They are most strongly pronounced at the cervix , but are continued forward on the urethra and backwards into the bladder . In the female they extend even to the meatus urinarius . The very oblique or circular fibres of the urethra are separated from the corresponding fibres of the prostate by the longitudinal , slightly oblique , and oblique fibres forming the outer half of the urethral wall and the inner portion of the prostate . The interval is particularly evident at the cervix , where the sphincter is most distinctly pronounced ; 1866 . ] 247 and here the two sets of very oblique or circular fibres have different axes . Further forward , or towards the apex of the prostate , the space gradually diminishes , the circular fibres of the gland curving in an upward direction into the verumontanum or caput gallinaginis , and blending with the circular fibres of the urethra . While , therefore , the very oblique or circular fibres of the urethra are entirely distinct at one point , they are indissolubly united at another . This is important , as it shows how the sphincter may act independently of the prostate , and the reverse . The longitudinal or vertical internal fibres posteriorly , connect the median or central portion of the trigone ( trigone vesical , trigonum vesicEe , Lieutaud ) with the verumontanum in the male , and the uvula and median ridge in the female . The slightly oblique internal fibres bound the trigone laterally , and are continued into the verumontanum , where they cross slightly . The oblique fibres which assist in forming the base of the trigone , are likewise continued in a downward direction on the verumontanum , where they cross , and are mixed up with the continuations of the very oblique fibres which form the sphincter at the neck , and with the circular fibres of the prostate . The arrangement of the fibres in the trigone resembles that found at the cervix and fundus generally , and the author is of opinion that Sir Charles Bell was in error when he described the " I muscles of the ureters " as separate structures . The ureters enter the vesical parietes at a very obtuse angle , and the angle increases according to the degree of distension of the bladder . These tubes receive accessions of fibres from the longitudinal , slightly oblique , oblique , and very oblique external and internal fibres of the bladder in their vicinity , and are continued upon each other within the bladder in the form of a strong transverse band . The transverse band which connects the ureters together within the bladder , or between the uretral orifices , is equal in volume to the ureters themselves within the vesical parietes . The band in question is best seen when the base of the bladder is detached and held against the light , and seems to be formed by the obliteration of the uretral tubes between the uretral orifices . The uretral channels seek the internal surface of the bladder even more obliquely than the ureters , and the inner walls of the ureters become so thin , particularly towards the uretral orifices , that they act mechanically as moveable partitions or valves , as in the smaller veins* . The canals of the ureters are consequently closed , partly by the contractions of the muscular walls , and partly by the mechanical pressure exercised by the urine about to be expelled . From the foregoing description it will be evident that the various sets of external and internal fibres forming the bladder , urethra , and prostate are antagonistic , not only as regards themselves , but also as regards the territory or region they occupy ; the loops formed by the anterior fibres crossing each other at more or less acute angles according to their depths , the anterior fibres , as a whole , crossing the posterior or homologous fibres as a whole . While , therefore , the fibres , in virtue of their twisted looped arrangement , antagonize each other individually , the aggregation of the fibres in any one region check , antagonize , and coordinate a similar aggregation of fibres at an opposite point ; the anterior fibres , e.g. , acting on the posterior , and the right lateral upon the left lateral . This arrangement , which is productive of great strength , ensures that the external and internal fibres shall act in unison or together , and fully explains the views of the older anatomists , who described the bladder as consisting of fibres crossing in every direction , and forming an intricate network . It likewise accords with the more modern opinion , that the fibres of the bladder may be divided into strata or layers . The fibres , when their points of attachment are taken into consideration , can only contract spirally from above downwards , and from without inwards ; they in fact converge , or close spirally in the direction of the cervix , which may be said to diverge or open in an opposite direction as the contraction proceeds . As a result of this twisting movement , the urine , like the blood , is projected spirally* . Finally , the fibres of the bladder , urethra , and prostate pursue at least seven well-marked directions ; the fibres crossing with remarkable precision at wider and wider angles , as the central portion of either is reached , as in the left ventricle of the vertebrate heart t. In fact , the fibres of the bladder and heart have a strictly analogous arrangement , and the author is inclined to believe that functionally also they possess points of resemblance . Yery similar remarks may be made regarding the structure and functions of the stomach and uterus .

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Results of the Magnetic Observations at the Kew Observatory.--No. III. Lunar Diurnal Variation of the Three Magnetic Elements. [Abstract]

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Edward Sabine

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Meteorology

Biography

Meteorology

XI . " Results of the Magnetic Observations at the Kew Observatory . -No . III . Lunar Diurnal Variation of the three Magnetic Elements . " By Lieut.-General EDWARD SABINE , P.R.S. Received June 21 , 1866 . ( Abstract . ) The subject of this paper is the lunar-diurnal variation of the magnetic declination and of the horizontal and vertical components of the magnetic force , derived from a seven years ' series of photographic records obtained at the Kew Observatory between January 1 , 1858 and December 31 , 1864 . The discussion which it contains has for its objects-st , to exemplify the consistent and systematic character of the llnar-diurnal influence thus derived ; and 2ndly , to serve both as a guide and as an encouragement to the several establishments at home and abroad which have adopted , or are Op. cit. p. 794 . t " On the arrangement of the Muscular Fibres in the Ventricles of the Vertebrate Heart , " by the author , Phil. Trans. part iii . 1864 , p. 451 . adopting the Kew methods of magnetic investigation . The completeness of the photographic process is shown by the fact , that of 175,344 hourly positions which should have been recorded in the interval under notice , there were only 1497 failures from all causes whatsoever ; and even of these few a considerable portion is shown to be due to the employment of the instruments in other experimental investigations . The paper contains a full statement of the processes of tabulation from the photograms , and of the different stages of reduction through which the tabular results were passed , for the purpose of deriving from them the facts connected with the lunar influence on the terrestrial magnetic elements . A lunardiurnal variation is shown to exist in each of these elements , of very small amount , but having peculiar and well-marked systematic characteristics . It is further shown that these characteristics present a similarity and accordance , which it is impossible to regard as accidental , with the results obtained at several other and widely-separated localities in the middle latitudes of both hemispheres , as for example at Iobarton , Toronto , Philadelphia , Pekin , and the Cape of Good Iope . A magnetic variation shown to be thus obviously dependent upon the moon 's position relatively to the terrestrial meridian , and agreeing in its principal features in such various localities , is urged by the author as being ascribable with great probability to the direct magnetic action of the moon , made sensible at the surface of the earth through the production of phenomena which , in the present state of our knowledge as regards the magnetism both of the earth and of the moon , it is as yet difficult wholly to explain , but which are likely to lead to a considerable advance of our knowledge in both these respects . The further prosecution of the investigation , both at Kew and elsewhere , is recommended as highly deserving the attention of those who occupy themselves in the pursuits of inductive philosophy .

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On the Congelation of Animals

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John Davy

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http://www.jstor.org/stable/112627

Biology 2

Chemistry 1

Biology

I. " On the Congelation of Animals . " By JOHN DAVY , M.D. , F.R.S. , &c. Received July 19 , 1866 . In a very interesting and elaborate paper by M. Puget , entitled " Sir la Congelation des Animaux , " published in the 'Journal de l'Anatomie et de la Physiologie , ' the Number for January and February of this year , he refers to a statement of mine , made many years ago* , that the leech may be frozen without loss of life . The experiments which he has instituted , and which appear to have been conducted with great care , have led him to an opp osite conclusion , viz. that congelation is not only fatal to the leech , but to animals generally , without a single exception . He considers the cause of death , the vera causa , to use his own words , to be an altered condition of the blood . In consequence of this statement , I thought it right Researches , Physiol. and Anat . ii . p. 121 . 250 to repeat the experiments on the leech , and to extend them to some other animals . They were begun at Oxford in May , in the laboratory of Professor Rolleston , with the kind assistance of Mr. Edward Chapman and Mr. Robertson ; and since then , in the following month , they have been continued at home in Westmoreland . At Oxford the trials were made on leeches and frogs ; at home , on these animals , and on the toad and some insects . The freezing mixture was made of pounded ice and common salt ; the temperature by it was commonly reduced to below 10 ? Fahr. , or at times so low as 2 ? or 3 ? . The results obtained were briefly the following:1 . A leech was exposed to the mixture in a small glass tube just large enough to hold it , using the tube for stirring the mixture . Taken out when perfectly rigid and hard , and gradually thawed , it showed when punctured a faint indication of irritability ; there was a just perceptible contraction of the part punctured , the oral extremity , and nowhere else . It did not revive . 2 . Another leech was similarly exposed , but for a shorter time . When divided by an incision , it was found not frozen throughout . When punctured , it showed marks of irritability in a slight degree stronger than the preceding : it soon died . 3 . Two leeches were similarly treated at home , and for a somewhat longer time ; the temperature reduced to 3 ? . These , when gradually thawed , one exposed to the air , the other left in the mixture , showed no marks of revival ; but they retained a certain elasticity , so that when bent they shortly recovered their former attitude , after a manner somewhat resembling a vital movement ; but inasmuch as they did not respond by the slightest contraction to puncture , it may be inferred that the movement was not vital . They resisted putrefaction for many days . 4 . A frog in a thin glass vessel was kept in the mixture about a quarter of an hour . It was very rigid when taken out ; thawed , no part on puncture afforded any indications of life ; watched two or three hours it proved to be dead . 5 . The heart of a frog , removed immediately after decapitation , whilst still pulsating , was subjected to the freezing mixture in a small glass tube . After having been frozen , on thawing it remained motionless , even when punctured . It had been kept in the mixture only a few minutes . 6 . The inferior extremities of a frog kept extended by a bandage and thus introduced into a glass tube , were submerged in the mixture , the body of the frog being held in the warm hand ; taken out after some minutes they were quite hard and motionless , whilst the body and upper extremities did not appear to be affected . It moved about , dragging the lower extremities as if they were dead . In about four hours it recovered the use of its femoral muscles ; on the following day the use of the muscles of the legs ; the day after it was able to bend and extend these limbs ; but there was no proof that its feet had recovered sensibility . On the fourth day it was found dead . 7 . The lower extremities of a large toad were immersed in direct contact with the mixture , the temperature falling to 3 ? . Gradually thawed , the parts showed no marks of life . This toad , which before the trial was in a dull state , afterward became almost torpid , and so continued until the following morning , when it was apparently dead : opened , the auricles were found feebly acting , ceasing after a few seconds* . 8 . A similar experiment was made on the lower extremities of an active frog , and with a similar result , except that the vivacity of the animal was for a short time but little impaired : after four hours it was apparently dead ; opened , its auricles contracted when punctured . It may be right to mention that , before exposing the toad and frog to the freezing mixture in direct contact , it was ascertained that the frog bore the immersion of its lower extremities in a saturated solution of common salt without any apparent loss of sensibility or motive powert . 9 . The lower extremities of an active frog of a large size were wrapped in tin-foil , and together with one of its upper extremities not so wrapped , were kept in a freezing mixture about a quarter of an hour . The frozen parts in thawing showed no marks of life . The frog died in about three hours . 10 . A cockroach , a flesh-fly , and a minute insect , an ichneumon * ( Celineus niger ? ) , confined together in a small glass tube , were kept some minutes in the mixture . Thawed , they were found all three dead . These results , so far as the particular instances are concerned , are sufficiently confirmatory of M. Puget 's , and on my mind they leave little doubt that his general proposition ( his inference from his very numerous experiments ) is correct , that congelation is fatal to animal life . It is hardly worth while to attempt to account for the different conclusion I had come to , that referred to by him relative to the leech , it being partly founded on the fact that leeches which had been enveloped in ice for many days were not thereby killed , and partly on witnessing some marks of vitality in leeches which were believed to have been artificially frozen , and which very soon after died . Whilst admitting that congelation , thorough congelation of an animal is incompatible with life , the cause of death from congelation seems open to question , and more especially that assigned by M. Puget as the vera causa , a change in the blood , and chiefly in its corpuscles . That these corpuscles are changed by freezing in form and condition seems to be certain . Before seeing M. Puget 's paper I had ascertained the fact , and not only that the corpuscles were changed , but also that the entire blood was to some extent altered , leading me at the time to ask whether some of the injurious effects of frost-bite may not be mainly owing to the freezing of the blood , and the changes in consequence in the corpuscles and in a less degree in the fibrin t ; and since , in examining the blood of the animals exposed to the freezing mixture , I have had this confirmed ; but the change in these instances was comparatively slight ; even in those of the congealed limbs of the frogs and toad the majority of the corpuscles appeared little altered ; some few seemed ruptured , some corrugated , and more contracted . Judging from the effect of congelation on the heart of the frog in experiment No. 5 , and from the effects of congelation partially produced , as in the extremities of the frog and toad , I would rather attribute the death to the freezing of the organs , not excluding the blood , than to the freezing of the blood alone ; and I would ask , is not this view most in accordance with the pathology of the subject , with all that we know of frost-bite and its consequences in man , and with the results of Mr. Hunter 's experiments on the local effects of congelation in animals-those on the ear of the rabbit and wottle of the cock ? and do not some evenl of M. Puget 's results give it support , such as the opacity of the crystalline lens , he admitting that , were it possible for an animal to revive after complete congelation , it would be blind from cataract ? Now , if the crystalline lens , if the bloodcorpuscles suffer and undergo an appreciable change from congelation , it would be very remarkable indeed did not the brain and nerves , and the organs generally suffer from the same cause , and experience changes incompatible with life . In the instance of man , we know that a certain reduction of his temperature merely , not reaching to congelation , suffices to extinguish life * , and that in the instances of other animals , especially the hybernating and insects , a moderate reduction occasions torpor , ending in death if too prolonged . That the organs generally suffer from congelation M. Puget himself admits , as expressed in the subjoined paragrapht . I have found , too , that the muscles , after having been frozen , exhibit a marked change ; thus , in one instance , that of a frog , in which , after decapitation , an upper and lower extremity were fiozen , the muscles of these limbs , when thawed , compared with those which had not been frozen , showed a well-marked difference under the microscope . Thus , whilst in the latter the striated structure was very distinct , in the former it was no longer visible ; and after a few hours , viz. on the following morning , whilst the unfrozen muscles had undergone no perceptible alteration , those which had been frozen had become of increased tenderness , yielding to a slight rending force , and breaking short , as if the coherence of the particles forming the fasciculi was greatly diminished .

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Letter to the President from Lieut.-Colonel Walker, R.E., F.R.S., Superintendent of the Trigonometrical Survey of India

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Lieut.-Colonel Walker

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10.1098/rspl.1866.0058

http://www.jstor.org/stable/112628

Meteorology

Astronomy

Meteorology

II . Letter to the President from Lieut.-Colonel WALKER , R.E. ) F.R.S. , Superintendent of the Trigonometrical Survey of India . " Dehra Done via Bombay , 31st May , 1866 . MY DEAR GENERAL , -Captain Basevi has just returned to my head quarters , on the close of the operations of his first field-season with the pendulums . You will be glad to hear that his progress has on the whole been very satisfactory . At the outset he met with numerous difficulties ; the xacuum apparatus was very troublesome , the air-pump constantly getting out of order , and the receiver as constantly leaking . It is very easy for philosophers to suggest improvements and refinements in the modus operandi of such operations , but it is not so easy to carry them out practically . Capt. Basevi has undergone a great amount of labour and anxiety , but he has successfully surmuounted all his difficulties . * Instances have occurred in the Lake District of persons who have perished on the hills from prolonged exposure to strong wind and rain , storm-stricken , in the language of the country . t ( ... La cong6lation complete a mime si profondement altere les tissus de l'organisme que quand l'animal est tout a fait degele , son corps est flasque et mou , ses cristallins sont blancs et opaques , et souvent sa coloration est tout a fait alter6e " ( p. 24 ) . He has taken experiments at the following stations , which you will find in the chart at the end of Everest 's description of the measurement of the Indian Arc , Dehra Done , Nojli , Kaliana , Dateri , and Usira . At Debra Done he took six sets of observations with each pendulum ; but finding he could advance more rapidly than the observatories could be got ready for him , at the subsequent stations he took ten sets of observations with each pendulum . Each set was carried over eight to nine hours , from 9 A.M. to 5 ' P.M. The pendulum was set in motion in the morning , the coincidences were observed , and the thermometers and arc of vibration were read hourly , until the set terminated in the afternoon . The first and last coincidences will be used only for determining the number of vibrations ; but the whole of the intermediate temperatures and arcs will be employed for determining the corrections for temperature and arc . He was very fortunate in his transits , only losing four nights in sixty ; complete sets of observations were twice taken at Kaliana ( the northern extremity of the Indian arc ) in December , when the temperature was lowest , and again this month when it was highest ; the range was not so great as we had anticipated , being 58 ? in the first instance , and 92 ? in the second , so that the results will scarcely be applicable to the observations at Kew , where , to the best of my recollection , the temperature was between 40 ? and 50 ? ; but they will amply suffice for all the observations that are likely to be taken in India . He endeavoured to observe at a constant pressure , but the leaking of the cylinder prevented this ; however , the whole range of pressure does not exceed 3 inches , and the average range is much less , the maximum being 5 inches and the minimum 2 . He is about to commence a series of observations at Masoori , at an altitude of about 6800 feet above the sea . He hopes to complete these during June , before the rainy season sets in , when transits will be impossible . During the rains he will be employed in completing the calculations connected with his experiments . By September I hope to be able to send you the final results . He has had so much to do in surmounting the difficulties arising from his new apparatus , that he could not manage to take any magnetic observations . In future , however , he hopes to be able to take these observations regularly at each of his pendulum stations . I trust that you will be gratified with this account of his first year 's operations . No pains have been spared to secure results of the highest possible value , and to reward the confidence you reposed in us , when you suggested to the India Office that we should undertake these delicate and difficult operations . Believe me , yours sincerely , General Sabine , P.R.S. J. WALKER .

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Spectroscopic Observations of the Sun. [Abstract]

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Proceedings of the Royal Society of London

J. Norman Lockyer

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Astronomy

Atomic Physics

Astronomy

III . ' Spectroscopic Observations of the Sun . " By J. NORMAN LOCKYER , F.R.A.S. Communicated by Dr. SHARPEY , Sec. R.S. Received October 11 , 1866 . ( Abstract . ) The two most recent theories dealing with the physical constitution of the sun are due to M. Faye and to Messrs. De la Rue , Balfour Stewart , and Loewy . The chief point of difference in these two theories is the explanation given by each of the phenomena of sun-spots . Thus , according to M. Faye - , the interior of the sun is a nebulous gaseous mass of feeble radiating-power , at a temperature of dissociation ; the photosphere is , on the other hand , of a high radiating-power , and at a temperature sufficiently low to permit of chemical action . In a sunspot we see the interior nebulous mass through an opening in the photosphere , caused by an upward current , and the sun-spot is black , by reason of the feeble radiating-power of the nebulous mass . In the theory held by Messrs. De la Rue , Stewart , and Loewyt , the appearances connected with sun-spots are referred to the effects , cooling and absorptive , of an inrush , or descending current , of the sun 's atmosphere , which is known to be colder than the photosphere . In June 1865 I communicated to the Royal Astronomical Society$ * ornptes itenclus , vol. ix . pp. 89-138 , abst , raeted in The Reader , ' 4th February , 1865 . t ' esearches oii Solar Physics . Printed for private circulation . Taylor and Francis , 1865 . t Monthly . Notices . Roy , Ast . 8 , oc ionl xxv . p , 2 37 [ Nov. 15 , 256 some observations ( referred to by the authors last named ) which had led me independently to the same conclusion as the one announced by them . The observations indicated that , instead of a spot being caused by an upward current , it is caused by a downward one , and that the results , or , at all events , the concomitants of the downward current are a dimming and possible vaporization of the cloud-masses carried down . I was led to hold that the current had a downward direction by the fact that one of the cloud-masses observed passed in succession , in the space of about two hours , through the various orders of brightness exhibited by faciulce , general surface , and penembr6e . On March 4th of the present year I commenced a spectroscopic observation of sun-spots , with a view of endeavouring to test the two rival theories , and especially of following up the observations before alluded to . The method I adopted was to apply a direct-vision spectroscope to my 6:-inch equatoreal ( by Messrs. Cooke and Sons ) at some distance outside the eyepiece , with its axis coincident with the axis of the telescope prolonged . In front of the slit of the spectroscope was placed a screen on which the image of the sun was received ; in this screen there was also a fine slit corresponding to that of the spectroscope . By this method it is possible to observe at one time the spectra of the umbra of a spot and of the adjoining photosphere or penumbra ; unfortunately , however , favourable conditions of spot ( i. e. as to size , position on the disk , and absence " of cloudy stratum " ) , atmosphere , and instrument are rarely coincident . The conditions were by no means all I could have desired when my first observations were made ; and , owing to the recent absence of spots , I have had no opportunities of repeating my observations . Hence I should have hesitated still longer to lay them before the Royal Society had not M. Faye again recently called attention to the subject . On turning the telescope and spectrum-apparatus , driven by clock-work , on to the sun at the date mentioned , in such a manner that the centre of the umbra of the small spot then visible fell on the middle of the slit in the screen , which , like the corresponding one in the spectroscope , was longer than the diameter of the umbra , the solar spectrum was observed in the field of view of the spectroscope with its central portion ( corresponding to the diameter of the umbra falling on the slit ) greatly enfeebled in brilliancy . All the absorption-bands , however , visible in the spectrum of the photosphere , above and below , were visible in the spectrum of the spot they , moreover , appeared thicker where they crossed the spot-spectrum . I was unable to detect the slightest indication of any bright bands , although the spectrum was sufficiently feeble , I think , to have rendered thei unmistakeably visible had there been any . Should these observations be confirmed by observations of a larger spot free from " cloudy stratum , " it will follow , not only that the phenomena Y2 presented by a sun-spot are not due to radiation from such a source as that indicated by M. Faye , but that we have in this absorption-hypothesis a complete or partial solution of the problem which has withstood so many attacks . The dispersive power of the spectroscope employed was not sufficient to enable me to determine whether the decreased brilliancy of the spotspectrum was due in any measure to a greater number of bands of absorption , nor could I prove whether the thickness of the bands in the spot-spectrum , as compared with their thickness in the photospherespectrum , was real or apparent only* . On these points , among others , I shall hope , if permitted , to lay the results of future observations before the Royal Society . Seeing that spectrum-analysis has already been applied to the stars with such success , it is not too much to think that an attentive and detailed spectroscopic examination of the sun 's surface may bring us much knowledge bearing on the physical constitution of that luminary . For instance , if the theory of absorption be true , we may suppose that in a deep spot rays might be absorbed which would escape absorption in the higher strata of the atmosphere ; hence also the darkness of a line may depend somewhat on the depth of the absorbing atmosphere . May not also some of the variable lines visible in the solar spectrum be due to absorption in the region of spots ? and may not the spectroscope afford us evidence of the existence of the " red flames " which total eclipses have revealed to us in the sun 's atmosphere ; although they escape all other methods of observation at other times ? and if so , may we not learn something from this of the recent outburst of the star in Corona ?

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On a Crystalline Fatty Acid from Human Urine. [Abstract]

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E. Schunck

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Chemistry 2

Physiology

Chemistry

IV . " On a Crystalline Fatty Acid from Human Urine . " By E. SCIUNCK , F.R.S. Received September 21 , 1866 . ( Abstract . ) After referring to the various forms in which fatty matter occurs in human urine , and to our extremely defective knowledge regarding its physical and chemical properties , the author proceeds to describe a process whereby he obtained from healthy urine a small quantity of a substance having the properties characteristic of the fatty acids which are solid at the ordinary temperature . The process consists in passing urine , after having been filtered in order to separate all insoluble matter which may have been deposited , through animal charcoal in an ordinary percolating apparatus . The urine is thereby completely decolorized and deodorized , a small quantity of charcoal producing this effect on a large quantity of urine . The charcoal , after being thoroughly washed with water , is treated with boiling alcohol , to which it communicates a bright yellow colour like * Irradiation would cause bands of the same thickness to appear thinnest in the more brilliant spectrum . 258 [ Nov. 15 , that of urine itself . The filtered alcoholic liquid is evaporated , and the residue is treated with water , which leaves undissolved a quantity of brownish-yellow fatty matter . This , after being purified in the manner described by the author , is found to consist principally of a fatty acid , having the properties characteristic of the group to which palmitic and stearic acid belong . The acid is white , crystalline , has a pearly lustre , melts at 54 ? '3 C. , volatilizes unchanged when heated , and is insoluble in water but easily soluble in alcohol and ether . It is soluble in caustic potash and soda-lye , in aqueous ammonia , and in solutions of carbonate of potash and carbonate of soda . The solutions froth on being boiled like ordinary soap and water . The potash compound is obtained from the watery solution in the form of small pearly scales , and from an alcoholic solution in prismatic crystals . The soda-compound separates from a boiling-hot solution on cooling as a thick , white , amorphous soap , a very small quantity of which is sufficient to cause the liquid to gelatinize . The watery solution of either of these compounds gives white curd-like precipitates with salts of barium , calcium , lead , and silver . The quantity of the acid obtained in the author 's experiments was too inconsiderable to enable him to determine its composition and atomic weight , and it therefore remains uncertain whether it is identical with any of the known fatty acids or not . The author inclines to the opinion that it is a mixture of stearic and palmitic acid , which according to modern investigations constitute together what was formerly called margaric acid . The author does not venture to assert that it forms a normal constituent of the healthy secretion , though the urine employed in his experiments in no case exhibited anything peculiar . The experiments described do not throw any light on the question how this acid , which belongs to a class of substances almost insoluble in water , comes to be dissolved in a liquid like urine , which is itself usually acid .

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On Oxalurate of Ammonia as a Constituent of Human Urine. [Abstract]

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E. Schunck

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Chemistry 2

Biology 2

Chemistry

V. On Oxalurate of Ammonia as a Constituent of Human Urine . " By I. SCHUNCK , F.R.S. Received November 15 , 1866 . ( Abstract . ) When ordinary healthy urine is passed through animal charcoal in the manner described in the preceding paper , several organic substances are separated and absorbed by the charcoal in addition to the fatty acid there referred to . The liquid obtained by treating the charcoal with boiling alcohol having been evaporated , the residue is treated with water , which leaves the fatty acid undissolved . The filtered liquid yields on evaporation a quantity of crystals , which , after being purified in the manner described by the author , are found to have the properties and composition of oxalurate of ammonia . The watery solution of the substance gives with acids a white crystalline precipitate of oxaluric acid ; with nitrate of silver it produces a precipitate which dissolves without change in boiling water , the solution on cooling depositing white silky needles of oxalurate of silver . The lead compound produced by adding acetate of lead to the watery solution , forms well-defined prismatic crystals . With chloride of calcium the watery solution gives no precipitate , but on adding ammonia and boiling , there is an abundant precipitation of oxalate of lime . By treatment with strong acids the substance is decomposed , yielding oxalic acid and urea . Its composition was found to correspond with the formula C 1-1 N3 0O , which is that of oxalurate of ammonia . The author 's experiments were not sufficiently numerous to decide the question whether this salt is . a normal constituent of human urine or not . There is no doubt , however , that its presence , whether exceptional or not , affords an easy and satisfactory explanation of a phenomenon which has until now proved very puzzling , viz. , the formation of oxalate of lime in urine long after its emission . It is doubtless owing to the decomposition of oxaluric acid , which takes up water and splits up into urea and oxalic acid ; the latter then combines with lime , of which there is always a sufficient quantity present to saturate the acid . There can be little doubt also that oxaluric acid is derived in the animal frame , as in the laboratory , from uric acid , the oxidation of which is its only known source .

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3701662

On the Structure of the Optic Lobes of the Cuttle-Fish. [Abstract]

260

261

Proceedings of the Royal Society of London

J. Lockhart Clarke

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Neurology

Biology 3

Neurology

VI . " On the Structure of the Optic Lobes of the Cuttle-Fish . " By J. LOCKHIART CLARKE , F.I.S8 . Received September 26 , 1866 . ( Abstract . ) The brain of the Cuttle-fish consists of several ganglia closely aggregated around the upper part of the oesophagus . The foremost or pharyngeal ganglion , which is much the smallest , is bilobed and somewhat quadrangular . The next is a large bilobed ganglion which forms the roof of the canal for the oesophagus . Beneath the oesophagus is another large and broad mass , which is connected on each side with the supra-cesopbageal masses by bands that complete the oesophageal ring . From each side of the cephalic masses springs a thick optic peduncle which ends in the optic lobe . Each optic lobe is larger than all the other cerebral masses taken together , and has a striking resemblance in shape to the human kidney . It is completely enveloped in a thick layer of optic nerves disposed in flattened bands which issue from all parts of its substance and proceed to the back of the eye in a fan-like expansion , the upper and lower bands crossing each other in their course . The substance of each lobe consists of two distinct portions , which differ from each other entirely in appearance . The outer portion resembles a very thin rind or shell , is extremely delicate , and very easily torn from the central substance which it encloses . It consists of three concentric layers-an external dark layer , an internal dark layer , and a middle pale and broader layer containing thin and concentric bands of fibres . The first or outer layer consists of a nultitude of nuclei and a fw small nucleated cells , with which filaments of the optic nerves-are connected . The second or middle layer is composed entirely of fine nerve-fibres which form two sets-one vertical , and the other horizontal . The vertical fibres issue at the under surface of the first layer from the network which its nuclei form with the fibres of the optic nerves . Some are continuous with the horizontal fibres , but the majority continue downward across them to the third or inner layer . At the junction of these two layers is a row of nucleated cells which send thin processes in different directions , and with which some of the nerve-fibres are connected . The third or inner layer is composed entirely of closely-aggregated nuclei , which are joined together in a network by the fibres which issue from the unlder surface of the middle layer . The cortical substance , consisting of these three layers , forms only a very small portion of the optic lobe . Out of the nulecar network of the inner layer fine nerve-fibres descend into the body of the lobe which it encloses . At first these fibres are vertical , parallel , and arranged in uniform series , with scattered nuclei between the m ; but as they descend to the centre of the lobe , they diverge more and more , and cross each other to form a plexus , first with oval and then with broader meshes , in which the nuclei and nucleated cells are collected into groups of corresponding shape and size . From the plexus at the inner side of the lobe bundles converge from all parts to form the lower half of the peduncle , the upper part of which consists of masses of small nuiclei , and gives attachment , by a short pedicle , to a small tubercle . This tubercle consists of closely-aggregated nuclei connected by fibres which converge to its neck and escape into the peduncle of the optic lobe . After concluding his description of the optic lobes , the author gives a short account of the structure and connexions of the remaining cerebral ganglia of the Cuttle-fish , with the view of determining their homologies . From the nature of the parts which it supplies , the foremost or pharyngeal ganglion weould seem to combine the function of the centres which give origin to the trigeminal , the olfctory , and the gustatory nerves in the vertebrata . The second bi ! obeed ganglion appears to correspond partly to the cerebral lobes and partly to the cerebellum of fshes . The posterior portion of the submcsophageal mass is the analogue of the medulla oblongata ; while the anterior portion may be regarded as the spinal cord concentrated below the csophagus and in the neighbourhood of the feet , which derive all their nerves from that source .

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On the Laws of Connexion between the Conditions of a Chemical Change and Its Amount. No. II. On the Reaction of Hydric Peroxide and Hydric Iodide. [Abstract]

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A. Vernon Harcourt|W. Esson

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Chemistry 2

Thermodynamics

Chemistry

I. " On the Laws of Connexion between the conditions of a Chemical Change and its Amount . " No. II . " On the Reaction of Hydric Peroxide and Hydric lodide . " By A. VERNON IlARcoUuT , M.A. , and W. ESSON , M.A. Communicated by Sir BENJAMIN COLLINS BRODIE , Bart. Received July 13 , 1866 . ( Abstract . ) In a former paper , of which an abstract appeared in the Royal Society 's Proceedings , vol. xiv . p. 470 , the authors gave an account of their first experiments on this subject . The second chemical change chosen for investigation was that which occurs in a solution containing hydric iodide ( hydriodic acid ) and hvdric peroxide . In this case the amount of change stands in relation to the following conditions , -(l ) the nature of the solution , that is to say , its temperature , and the nature and quantity of the different ingredients which it contains in a unit of volume , ( 2 ) the quantity of the solution , or the number of such iunits of volume , ( 3 ) the time during which the change proceeds . The relation of the amount of change to the second and third of these conditions is determinate : it varies directly with each ; for the solution is homogeneous , and , if all other conditions are fixed , the rate of change is uniform . But the first condition comprises an almost indefinite number of particular conditions ; for not only may various iodides and per oxides be used without , as far as we know , altering the nature of the reaction , but other substances may be introduced into the solution , and their influence upon the amount of change determined . The present paper contains an account of the methods employed for observing this reaction , and of the results obtained by varying two particular conditions , namely the amounts of peroxide and of iodide . If hydric peroxide and hydric iodide , or barytic peroxide , potassic iodide , and hydric chloride , be brought together in dilute solution at the ordinary temperature , a gradual development of iodine takes place . If a drop of a dilute solution of sodic hyposulphite be added to the mixture capable of reducing to iodide all the iodine which has been formed up to the time of its addition , but not all that will be formed in the course of the reaction , the liquid which had become yellow becomes colourless , remains colourless for a while , and then suddenly becomes yellow again . This yellow colour may be exchanged for a more intense blue colour by putting starch into the solution . It was found that in dilute solutions no direct oxidation of hyposulphite by peroxide took place ; and that the quantity of hyposulphite required to reduce the iodine liberated by a measure of peroxide was the same , whether the hyposulphite were added little by little during the course of the reaction , or after the primary reaction had completed itself , and when no peroxide remained in the solution . The method of observation founded upon these facts was briefly as follows : Measured quantities of all the standard solutions , except that of hydric peroxide , were introduced into a glass cylinder about 11 inches high by 3 broad , and water was added till the upper surface of the liquid was level with a line drawn round the cylinder . This adjustment of volume was made through a hole in the bung , which closed the cylinder ; two other holes admitted a thermometer and an inverted funnel-tube . A current of carbonic acid passing down the funnel-tube to the bottom of the cylinder , and rising in large bubbles from the mouth of the funnel , served at once to stir the liquid constantly , and to protect its upper surface from the air . When the volume and the temperature of the solution had been adjusted , a small measure of hyposulphite was first added , and then the pipetteful ( 10 cub. centims. ) of peroxide . The cylinder was placed on a sheet of white paper in front of a clock beating seconds . By watching the surface of the fluid and counting the seconds when the time of an observation was near , it was possible to note accurately the moment at which the colour changed . A second small measure of hyposulphite was then introduced , and at the proper interval a second observation was made . Each such addition of hyposulphite , with the observation preceding and following it , is spoken of as an experiment , and these experiments were continued until the reducing power of the last measure of hyposulphite being greater than the oxidizing power of the remaining peroxide the blue colour did not return . The small measures of hyposulphite consisted of single drops collected under circumstances favourable to their perfect uniformity . The peroxide employed was either an acidified solution of sodic peroxide , or dilute hydric peroxide obtained by the distillation of such a solution . In each set of experiments the value of the measures of hyposulphite and of the pipetteful of peroxide could be compared by determining what fraction of a measure of hyposulphite remained in the solution when the set of experiments had been brought to an end . These values could also be compared by determining each with a standard solution of potassic permanganate . In presence of an excess of potassic iodide , sodic hyposulphite may be estimated by this reagent exactly as it may by standard iodine solution . During each set of experiments , then , all the conditions of the reaction are constant except two , which are progressively modified . One of these is immaterial , the accumulation of a small quanitity of sodic tetrathionate ; the other is material , the gradual disappearance of the small quantity of peroxide upon whose presence the reaction depends . The first point , therefore , requiring to be investigated was the law of connexion between the amount of change and the amnount of peroxide . Since the amount of peroxide originally taken is known , and also the amount which corresponds to a measure of hyposulphite , the amount remaining in the solution at the moment of each observation is also known . Thus the data supplied by each experiment are ( 1 ) the amount of peroxide present in the solution at a particular moment of time , ( 2 ) the time at which this amount is present , ( 3 ) the amount present at a subsequent moment of time , ( 4 ) the time at which this amount is present . Representing these two amounts of peroxide by y and y1 respectively , and the corresponding moments of time by t and t ' , the result of each experiment is that an amount of chemical change y-y ' has been accomplished in an interval tt-t . According to the hypothesis proposed in our former paper , namely that the amount of chemical change varies directly with that of each of the substances partaking in it , these quantities should exhibit throughout a set of experiments the constant relation y_eQ(t'-t ) The numerical results obtained in various sets of experiments performed under different circumstances are compared with those calculated from equations of this form , and the two are shown to agree within narrow limits of experimental error . It is inferred that in this case the amount of chemical change taking place at any moment is proportional to the amount of peroxide present at that moment in the solution . The constant a in the preceding equation represents the effect upon the amount of change of those conditions which do not vary in a set of experiments ; and it is possible by varying one of these conditions in different sets of experiments , and determining the value of a in each , to inquire into the law of connexion between the condition thus varied and the amount of change . Accordingly a series of sets of experiments was made , in which , all else being kept constant , different quantities of potassic iodide were used in different sets . It is shown that the values of a derived from the different sets of experiments are proportional to the quantities of iodide used in each case . In this series hydric sulphate was an ingredient of the solutions ; a second series was made , in which an equivalent quantity of hydric chloride was substituted . The result , as regards the effect of varying the amount of iodide , was the same as in the previous series . The rate of chemical change , that is to say the amount in a given time with a constant quantity of peroxide , was found to be directly proportional to the amount of iodide in the solution . Thus the law of connexion is the same in this case as in that already investigated of the variation of peroxide . The total amount of chemical change is a function of all the conditions of the system in which it occurs . If we call this amnount X , the volume of the solution v , its temperature t , the time during which the change proceeds t , and the amounts of the various ingredients , peroxide , iodide , &c. in a unit of volume , p , i , a , b , c. . , then f(a , b , c,. . A ... , ... t. . v ... ) . The form of this function is determinate in the case of two of these conditions , viz. v , t , and has now been determined experimentally in the case of p and i , so that the equation may be written in the form E:=i-p t v. f ( a , c ... . . ) . The number of ingredients , represented by a , 6 , c , &c. , which may be introduced into the system and affect the amount only , and not the nature of the chemical change , and which may therefore be regarded as so many conditions of the reaction , is doubtless very large . The authors believe that the investigation of the influence of some of these may prove of interest , it being possible thus to compare various substances which may be substituted one for another in the system by a new standard . They find , for example , that comparing equivalent quantities ( in the ordinary chemical sense ) of hydric sulphate and hydric chloride , the effect of the latter is nearly double that of the former . But the most important condition of the change whose influence is still undetermined is that of temperature , for this condition intervenes under all circumstances of the reaction , and indeed in all chemical changes whatever . The authors have already made many experiments on both these points . The results of this investigation , which will complete the study of the reaction , may , they hope , formf the subject of a subsequent communication .

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On the Stability of Domes.--Part II. [Abstract]

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E. Wyndham Tarn

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Measurement

Fluid Dynamics

Measurement

II . " On the Stability of Domes."-Part II . By E. WYNDHAM TARN , M.A. , Memb. Roy . Inst. Brit. Architects . Communicated by G. GODWIN , Esq. Received October 23 , 1866 . ( Abstract . ) In a former paper on this subject which the author presented to the Royal Society , and which is published in the 'Proceedings ' ( vol. xv . p. 182 ) , he obtained formulae for calculating the thrust of a spherical dome of uniform thickness , by supposing it to consist of a number of thin ribs , each of which is formed by two vertical planes intersecting at the axis of the dome , and making a small angle with each other ; and then treating each rib as forming , with the corresponding one of the opposite side , a complete arch . In the present paper the author applies the same method to domes of other forms than the spherical . The following are the kinds for which the formulm are investigated : A. The Gothic dome , of which that of the cathedral at Florence is a splendid example . This kind has for its section a pointed arch formed by two segments of circles , the centre from which each is struck being on the springing line , but not in the axis of the dome . The author denotes by a the angle between the vertical and a line drawn from this centre to the point , near the crown of the dome , where its axis is intersected by a circle drawn around that centre with a radius equal to the mean of the radii of the circles which generate the outer and inner surfaces of the dome , and reduces his results to numbers for three different values of the angle a. B. A dome whose inner surface is a paraboloid of revolution , the thickness of the shell being uniform throughout . C. The dome whose surface is formed by the revolution of an ellipse about its major axis . In the investigation , the two surfaces are supposed to be generated by the revolution of two concentric elliptic quadrants , whose major axes differ from one another by the same quantity as the minor axes , so that the thickness is very nearly uniform throughout . D. A form of dome commonly used in eastern countries , sometimes called the ogival dome , the surface of which is generated by the revolution of a curve which has a point of contrary flexure . In the investigation , the author takes for this curve the curve of sines , the equation of which is y'=r sin- , where x ' , y ' are the vertical and horizontal coordir nates of a point in the generating curve , and supposes the outer and inner surfaces to be generated by the revolution of two such curves , differing only by the value of r , the origin being the same . The following Table exhibits the principal results obtained from the author 's investigations . All the domes , except the last , are supposed to be of the uniform thickness throughout of 1 foot . In the last the thickness is 1 foot at the springing , but gets rather less towards the top . The domes are supposed to be built of material weighing 125 lbs. to the cubic foot . The thrust is calculated for the 180th part of the whole dome , being the portion cut out by two planes which make an angle of 2 ? at the axis . Table showing the position of the weakest joint in domes of various forms , and the horizontal thrust at that joint . Greatest horiPosition of the weakest ; ltt h Form of Dome . Span . joint , or joint where oal thrust a or thrust at thrust is greatest . est j weakest joint . lbs. 1 . Hemisc~ fact . ~ Malakes with springing line 201 1 . H emisphere ... ... ... ... . . 2a ... . i{ angl of 20 9201 Hemispe1 r 20 an angle of 20 ? . f 2 . Gothic , a -10 ... ... . . Makes with springing line 88'7 a20 l an angle of 17 ? . 3 . gothic , a{22-2 0 . 20 { } Makes with springing lineil 3 . Gothic , a=22- ... ... ... ... .{^anSTo ? r^^^^^ 80 ? 418 4 . Gothic , a=30 ... ... ... ... ... { 77-27 4 . GoiC , a-o *--30 0.@@@ 20 l Makes with springing line }727 5 . Parabolic ; height above springing equals th half 2 At springing line 79-6 span . 6 . Elliptical , major axis verOne-third of semimajor tical ; ratio of major to 0 axis above springing 90-867 minor axis as 6 : 5 . 1 line . 7 . Ogival ; contour , the " curve J One-sixteenth of the span l 625 of sines . " 20 above springing line . I In the preceding cases , except the last , the domes are assumed to be of uniform thickness . The author finally applies his formulae to the case of the spherical dome in which the thickness at the crown is one-half that at the springing , the inner surface being generated by the revolution of a circular quadrant whose centre is raised above the centre of that which generates the outer surface by half the difference of the radii . Assuming the outer and inner radii R , r to be respectively 11 feet and 10 feet , he finds that the weakest point on a dome of this form appears to be at a height equal to LR above the springing line ; and with the other numerical values , assumed the same as before , he finds for the horizontal thrust at the weakest joint 55178 lbs. For each kind of dome the author forms what he calls the equation of stability , giving , for an assumed value of the height of the pier , the least thickness t which will permit of stability . The following are the results for each kind of dome , the height of the pier being taken at 50 feet : Spherical dome ( from former paper ) ... t=2'45 feet . Gothic dome ( a==22 ) ... ... . t=2-259 , Parabaloidal domee ... ... . t-=2244 , , Elliptic dome ... ... ... . . t244 , , Ogival dome ... ... ... 2 , , Spherical dome ( thinner at crown ) ... . t= 1'9 The author considers what he has found as the weakest part of a dome to be the position in which an iron belt must be placed to produce the greatest effect in counteracting the thrust of the dome . If this be done , the thickness of the pier may be considerably diminished , and need not greatly exceed the strength necessary for supporting the superincumbent weight acting vertically downwards .

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A Supplementary Memoir on Caustics. [Abstract]

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268

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A. Cayley

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Formulae

Optics

Mathematics

III . " A Supplementary Memoir on Caustics . " By A. CAYLEY , F.R.S. Received November 15 , 1866 . ( Abstract . ) It is near the conclusion of my " Memoir on Caustics , " Phil. Trans. vol. cxlvii . ( 1857 ) , pp. 273 , 312 , remarked that for the case of parallel rays refracted at a circle , the ordinary construction for the secondary caustic cannot be made use of ( the entire curve would in fact pass off to an infinite distance ) , and that the simplest course is to measure off the distance GQ from a line through the centre of the refracting circle perpendicular to the direction of the incident rays . The particular secondary caustic , or orthogonal trajectory of the refracted rays , obtained on the above supposition was shown to be a curve of the order 8 ; and it was further shown by consideration of the case ( wherein the distance GQ is measured off from an arbitrary line perpendicular to the incident rays ) , that the general secondary caustic or orthogonal trajectory of the refracted rays was a curve of the same order 8 . The last-mentioned curve in the case of reflexion , or for t , =-1 , degenerates into a curve of the order 6 ; and I propose in the present supplementary memoir to discuss this sextic curve ; viz. the sextic curve which is the general secondary caustic or orthogonal trajectory of parallel rays reflected at a circle .

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Anniversary Meeting

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http://www.jstor.org/stable/112636

Biography

Optics

Biography

III . " A Supplementary Memoir on Caustics . " By A. CAYLEY , F.R.S. Received November 15 , 1866 . ( Abstract . ) It is near the conclusion of my " Memoir on Caustics , " Phil. Trans. vol. cxlvii . ( 1857 ) , pp. 273 , 312 , remarked that for the case of parallel rays refracted at a circle , the ordinary construction for the secondary caustic cannot be made use of ( the entire curve would in fact pass off to an infinite distance ) , and that the simplest course is to measure off the distance GQ from a line through the centre of the refracting circle perpendicular to the direction of the incident rays . The particular secondary caustic , or orthogonal trajectory of the refracted rays , obtained on the above supposition was shown to be a curve of the order 8 ; and it was further shown by consideration of the case ( wherein the distance GQ is measured off from an arbitrary line perpendicular to the incident rays ) , that the general secondary caustic or orthogonal trajectory of the refracted rays was a curve of the same order 8 . The last-mentioned curve in the case of reflexion , or for t , =-1 , degenerates into a curve of the order 6 ; and I propose in the present supplementary memoir to discuss this sextic curve ; viz. the sextic curve which is the general secondary caustic or orthogonal trajectory of parallel rays reflected at a circle . November 30 , 1866 . ANNIVERSARY MEETING . Lieut.-General SABINE , President , in the Chair . Dr. Gladstone , on the part of the Auditors of the Treasurer 's Accounits appointed by the Society , reported that the total receipts during the past year , including a balance of ? 15 9s . carried from the preceding year , amounted to '4295 16s . lid . ; and that the total expenditure in the same period amounted to ? 3629 15s . 5d . , leaving a balance of ? 638 8s . ld . at the Bankers , and of X27 13s . 5d . in the hands of the Treasurer . The thanks of the Society were voted to the Treasurer and Auditors . The Secretary read the following Lists Fellows deceased since the last Anniversary . Royal . His Majesty Leopold , King of the Belgians , K.G. On the -Home List . Benjamin Guy Babington , M.D. William Thomas Brand , D.C.L. Right Hon. Sir James Lewis Knight Bruce , Knt. , D.C.L. Richard John Hely H-utchinson , Earl of Donoughmore . Sir Charles Locke Eastlake , D.C.L. Joseph Edye , Esq. G. W. Featherstonhaugh , Esq. Charles Lord Glenelg , D.C.L. William Gravatt , Esq. John Scandret HIarford , D.C.L. Charles James I-argreave , LL. D. William Henry Harvey , M.D. Robert H-unter , Esq. Percival Norton Johnson , Esq. Edward Kater , Esq. John Lee , LL. D. Rev. Samuel Roffy Maitland , D.D. Thomas Spring Rice , Lord Monteagle of Brandon . Francis Thornhill Baring , Baron Northbrook . I-oratio William Walpole , Earl of Orford ( in 1858 ) . George Rennie , Esq. HI-enry Darwin Rogers , LL. D. Edward James Seymour , M.D. Samuel Reynolds Solly , Esq. Joseph Toynbee , Esq. Lieut.-Col. Sir John Maxwell Tylden , Knt. Rev. William Whewell , D.D. Right Hon. Sir James Wigram , Knt. , M..A . Nicholas Wood , Esq. On the Foreign List . Georg Friedrich Bernhard Riemann . OChange of NVamne . Rev. IHenry Christmas to Noel-Fearn , Defaulter . Colonel John Le Couteur . Fellows elected since the last Anniversary . On the Home List . John Charles Bucknill , M.D. The Ven . John Henry Pratt , f.A. Rev. Frederic William Farrar . Capt. George Henry Richards , R.N. William Augustus Guy , M.B. Thomas Richardson , Esq. , M.A. James Hector , M.D. WVilliam Henry Leighton Russell , John William Kaye , Esq. Esq. Hugo Miiller , Ph. D. Rev. William Selwyn , D.D. Charles Murchison , MII . D. Rev. Richard Townsend , M.A. William Henry Perkin , Esq. Henry Watts , B.A. On the Foreign List . Franz Cornelius DondCers . Gustav Rose . Georg Friedrich Bernhard Riemann . Reacdmitted . William Bird HI-erapath , M.D , The President then addressed the Society as follows : GENTLEMEN , DURING the autumnal recess , and in the absence of the President , the Treasurer , on learning that the Government had it in contemplation to assign the main building of Burlington House , now appropriated to the Royal , Chemical , and Linnean Societies , to the Royal Academy ( together with ground in its rear for the erection of additional buildings ) , deemed it advisable in the interests of the Society , and after consultation with the Senior Secretary , to address a letter to the Earl of Derby . The officers of the Society were referred by his Lordship to the Chief Commissioner of Works , by whom they were informed in reply that due provision was to be made for the Societies , and that the Architects , Messrs. Banks and Barry , with whonr the Office were to advise on the subject , were instructed to confer with the Council of the Royal Society . Those gentlemen having accordingly communicated to the Council that they are directed to report to the Government on the accommodation that can be provided for the Royal and the other Societies in new buildings , to occupy part of the space between Burlington House and Piccadilly , the Council have appointed a Committee to consider the whole matter and to confer with the Architects thereupon . The Committee have had an interview with Mr. Banks , and have handed in a statement setting forth the nature and extent of accommodation that will be required for the Society in lieu of their present apartments . There , so far as we are informed , the matter rests for the present , but from the tenor of the communications which have passed , there seems every reason to feel confident that the Society will be suitably and amply provided for . I had the pleasure of announcing at the last Anniversary that the printing of the Catalogue of Scientific Papers , in the preparation of which we have been so long engaged , was at length commenced . Twentyeight quarto sheets are now printed and eight more are in type . The work would now have been further advanced , had not the Superintending Commitee in the mean time obtained access to additional Periodical Works , containing TMemoirs deserving , to be included in the Catalogue , and too numerous to warrant their being postponed for a supplement . The printing has therefore been interrupted for a time in order to allow of the insertion of these additional titles in their proper places . Moreover , proofs of every sheet are supplied to several of the Members of the Library Committee who separately revise them ; and this mode of proceeding no doubt somewhat protracts the work , but it has the more than compensating advantage of securing the greatest attainable accuracy . The attention of your Council has been much occupied in the past year in complying with a request from Her Majesty 's Government for the advice and co-operation of the Royal Society in the re-organization of the Meteorological Department of the Board of Trade , and in preparing the preliminary arrangements for the establishment of a system of British LandMIeteorology to be carrieed out under the authorization of that Board . Perhaps there is no branch of scientific research in which a greater amount of human labour has been expended than has been the case in Meteorology , -a natural consequence of its intimate connexion in so many ways with the interests and pursuits of man ; and it may perhaps be said with equal truth that there is no department of natural knowledge in which the labour bestowed has beein of a more desultory character , or the value and importance of the conclusions less commensurate with the time and labour bestowed on their acquisition . The object to be desired , therefore , is scarcely so much to give a stronger impulse to the spirit of inquiry , as to aid in giving to that which exists a more systematic direction . This has been attempted in several of the continental States of Europe and America , by the establishment at the expense of the respective governments , and under the superintendence of men eminently qualified by theoretical and practical knowledge , of systematic climatological researches ; and , as regards the individual states themselves , it may be confidently said that the results have been very beneficial . For some time past it lias been desired to establish a closer connexion between these independent and separate systems of observation , by effecting an assimilation of instrumental means , and of the modes and times of observation . It was chiefly in this view that the assemblage took place by special invitation , at the Cambridge Meeting of the British Association in 18-15 , of the Directors of the principal meteorological ( and magnetical ) observatories in Europe and America ; and that a second meeting took place at Brussels in 1853 . The difficulty that impeded success on these two occasions cannot be better stated than in the words of Captain ; faury , in his Report to the Government of the United States , by whom he had been appointed to visit the principal European Meteorological Observatories for the express purpose of urging a uniformity of procedure . " I would recommend that the United States should abandon , for the time at least , that part of the ' Universal System ' which relates to the Land , and that we should direct our efforts mainly to the Sea , where there is such a rich harvest to be gathered for navigation and commerce . I am inclined to make this recommendation in consequence of the evident reluctance with which Russia , Austria , Bavaria , Belgium , and other powers seem to regard any change in their systems of meteorological observations on shore . Each country seems to have adopted a system of its own , according to which its labourers have been accustomed to work , and to which its meteorologists are more or less partial . Any proposition having in view for these systems a change so radical as to bring them into uniformity , and reduce them to one for all the world would , I have reason to believe , be regarded with more or less jealousy by many , -not so , however , with regard to the sea ; that proposal meets with decided favour and warm support . " The most hopeful way of removing the difficulties which impeded the adoption of a system in which all might willingly unite was obviously the introduction of instruments which should be continuously self-recording , and which , after sufficient trial , should receive general approval . The importance of such a substitution had been recognized at the Observatory of the British Association at Kew at a very early date , even before the Cambridge Meeting of the British Association in 1845 ; and at that meeting the satisfactory performance was announced of a photometrically selfrecording barometer , self-compensated also for temperature , devised by Mr. Francis Ronalds , the Honorary Director of the Kew Observatory , the same to whose merits in regard to the instantaneous transmission of messages by means of electricity , at the very early date of 1823 , attention has been recently called in the public journals . Encouraged by this success in one instrument , the Directors of the Kew Observatory proceeded , as rapidly as the means at their disposal enabled them to do , towards the provision of self-recording instruments for the other meteorological elements ( as well as for the magnetical elements ) , and were considerably advanced in their preparations when in 1854 the Board of Trade informed the President and Council that , in fulfilment of a previous earnest recommendation to that effect from the Royal Society , they were " s about to submit to Parliament an estimate for an office for the discussion of observations on meteorology made at sea in all parts of the globe ; " adding that , ( " as it may possibly happen that observations on Land upon an extensive scale may hereafter be made and discussed in the same office , it is desirable that the Royal Society should keep in view and provide for such a contingency . " The subject of a Government system of 1Meteorological Observations on Land was again brought under the consideration of the Royal Society in a letter from the Board of Trade in N:ay 1865 , and the President and Council were expressly requested to offer suggestions in reference to it . The suggestions which they offered in reply have been made known to the Society , in their leading outlines at least , in my Address of last year , and in No. 82 of our ' Proceedings . ' They have been submitted by the Board of Trade to a Committee appointed by itself , whose general approval they are understood to have received ; and the whole scheme is now under the consideration of Government in respect to its cost . The sea-observations , so hopefully spoken of by Captain Maury , were the subject of a very full communication addressed by the President and Council of the Royal Society to the Board of Trade in February 1855 , and the recommendations contained therein were made the basis of the instructions given to the Meteorological Office of the Board of Trade at its first formation . The collection of what have since been comprehended under the general designation of " Ocean Statistics " proceeded for some time with much activity and success under the direction of our lamented Fellow the late Admiral FitzRoy . His exertions and those of his assistants were afterwards in great measure diverted to an object which , if it could be-or , to speak more sanguinely , whenever it shall become-practically attainable with a fair measure of scientific certainty , will assuredly both deserve and receive in the highest degree general favour and support . I mean the system popularly known by the appellation of " storm-warnings . " Meanwhile , if the recommendations of the Royal Society and the intentions entertained by the Board of Trade shall now receive the hoped-for sanction of the general government , the collection of ocean statistics and their systematic combination will be resumed with fresh vigour , and with all the aids which experience and matured scientific consideration can afford ; and at the same time , if our hopes respecting the proposed system of Land-Meteorology are realized , and if its fruits correspond in a fair degree to the expectations which we venture to form respecting them , we shall gradually obtain such a more complete knowledge of the laws which govern the changes of weather in the British Islands and their vicinity , as may enable the predictions of approaching storms or " storm-warnings , " if now suspended , to be resumed hereafter , and at no very distant period , with far greater confidence and more assured advantage . At our last Anniversary I acquainted you that the Legislature of Victoria hadvoted the sum of 5000 for the construction of a large reflecting telescope to be erected at Melbourne and employed in a thorough survey of the Nebulsm and multiple stars of the southern hemisphere . They also requested the cooperation of the President and Council of the Royal Society in arranging a contract for the work and superintending its execution . We selected for the task one of our Fellows , Mr. Grubb of Dublin , whose well-known optical and mechanical talents gave sure promise of success , and we obtained for him the advantage and assistance of a Superintending Committee , consisting of our late President the Earl of Rosse , Dr. obinson , and Mr. Warren z De la Rue . The contract for the work was signed on the 19th of January ; the progress has been rapid , and I have great pleasure in informing you that , according to all appearance , the instrument will be ready for trial in the spring of 1867 . All the large parts of it are ready for mounting , and the rest considerably advanced . The lattice-tube , the appearance of which is known to many of us from the photographs , is put together . It is made of ribs of steel to combine lightness and strength ; they are rolled taper to effect this in the highest degree . The equilibrated systems of levers which support the great speculum , with their boxes , are of the same material and are also completed . Three specula have been cast on a plan differing from that of Lord Rosse only by such modifications as were made necessary by their having central apertures . The first speculum came out sound from the annealing furnace , but had two blemishes on its surface which would have required a month to grind out , and Mr. Grubb broke it up without hesitation , though not many years ago such a disk would have been almost inestimable . The second cast has been successfully ground , and its surface is faultless . The third , a duplicate speculum , was cast on the 24th of October . The grinding has been performed by the polishing machine and steam-engine which belong to the telescope , and will accompany it to Melbourne . The trial-piers on which the instrument is to be set up for the examination of the Superintending Committee , are ready . At the request of the Board of Visitors of the iMelbourne Observatory , and at the recommendation of the aforenamed Superintending Committee , I have appointed as Observer with this telescope IMr . Albert Le Sueur , a Graduate at Cambridge and a Wrangler in 1863 . Ie is at present training himself in sidereal astronomy at the Cambridge Observatory under the guidance of Professor Adams , and will be present at the polishing of the specula . ir . De la Rue has kindly promised to instruct him in the practice of celestial photography ; so that there is reason to hope that this magnificent instrument will be used with full intelligence and zeal , and amply repay the munificent spirit that has guided the Legislature of this energetic and prosperous colony . The large appropriation made by the Colony of Victoria for the construction of this telescope and for its accompanying spectroscope , and for a suitable provision for its effective employment at Melbourne , have not been the only manifestation in the present year of the enlightened spirit which animates and guides the Legislature of that colony . A sum has been remitted and received in this country for the purchase of a complete equipment of self-recording magnetical instruments on the model of those at the Kew Observatory , to be located in the Government Reserve adjacent to the Melbourne Astronomical Observatory , and to be empioyed under the superintendence of its director , Mr. Ellery . The instruments have been made and verified under the immediate care of the Director of the Kew Observatory , and have been despatched to their destination . system of intended observation is modelled on that exemplified at the Kew Observatory . The intention , adverted to in my last year 's Address , of the Government of Miauritius to establish there a magnetic observatory , working with the instruments and adopting the methods exemplified at Kew , has been since matured . The necessary funds have been remitted , and the instruments are made and are now under process of verification , at Kew , where Professor Mfeldrum , the Director of the Mauritius Observatory , is daily expected to arrive , with the view of making himself thoroughly acquainted with the instruments , and with the processes in which they are to be employed . The geographical position of iMauritius is a very important one , both for magnetical and meteorological observations . Hitherto meteorology has been exclusively pursued there , and the researches of Professor lCeldrun on the cyclonic storms which prevail in the vicinity of the Island are well known . Those of our Fellows who remember the assiduity and devotion to scientific pursuits manifested by Mr. Charles Chambers during his employment as one of the assistants of the Kew Observatory , will be glad to learn that he has received from the Government of Bombay the temporary appointment of Superintendent of the Bombay Magnetical and Meteorological Observatory , and in that capacity has been required to submit a scheme for the reorganization of the observatory , with instruments and methods of research suitable to the advance which has been made in these respects in the last twenty-five years . 3r . Chambers 's report is understood to be on its way from the Government of Bombay to the India Office , with a view to its being submitted to the consideration of the President and Council of the Royal Society ; and should it be approved , it will probably lead to the permanent employment of 3Mr . Chambers in his present temporary position , and to the thorough utilization of the observations of past years , in addition to the prospect of most efficient work at this observatory , under the best conditions , both personal and material , for the future . I have to add to the list of magnetic observatories established in the present year one at the Roman Catholic College at Stonyhurst , supplied with the Kew instruments , and pursuing the same methods of observation and reduction . I refer to this with the greater satisfaction , because in addition to the value to science of the actual work performed at the observatory , it may be expected to be , and is expressly designed by the authorities of the College to be a means , amongst others adopted by them , of fostering among the students a taste for scientific pursuits , which may remain with them in after life . For this latter purpose Stonyhurst has added to the more ordinary modes of instruction in natural knowledge that practical instruction which is only to be gained by working under proper tuition in observatories and laboratories directed to special scientific pursuits , among which magnetism , terrestrial and celestial , may now be considered to have taken its place . It was from the twofold motive of aiding the advancement of science by this additional observatory on the one hand , and on the other of contributing to the dissemination of a taste for scientific pursuits among a large class of our gentry , that the Council of the Royal Society thought it right to allot last year from , the parliamentary grant annually placed at their disposal , a sum sufficient to defray half the cost of a set of magnetical iun struments for Stonyhurst . This is the fortieth year since Mr. Schwabe began at Dessan his series of observations on the Solar spots , which he has continued without intermission from 1826 to the present time . Impressed with the extreme desirableness of continuing beyond the limits of a single life a series already so valuable , the Committee of the Kew Observatory concerted with Mr. Schwabe for the commencement last year at Kew of a series which should run parallel with his for a time , and which afterwards , when the identity or proximate identity of the two should have been established , might , it was hoped , be prolonged indefinitely through future years . Mr. Schwabe 's observations and those at Kew have accordingly been proceeding contemporaneously , and the comparison between their results during the ten months from January to October 1866 inclusive , gives reason to believe that the object will be satisfactorily attained . The number of new groups of spots observed at the two stations in the ten months is identical , and very similar , if not always quite identical , in each single month ; although , as might have been expected from the difference between the continental and insular climates , the number of days of observation at Kew is considerably less than at Dessau . The results of the first year 's experiments with the pendulums which were noticed in my last year 's Address as having been supplied to the Indian Trigonometrical Survey , have been received from Colonel Walker , IIR . A. , F.R.S. , Superintendent of the Survey . They were made by Captain Basevi at several stations where the triangulation is now proceeding . Ina letter to myself accompanying them , dated August 30 of the present year , Colonel Walker says , " Already these experiments are beginning to throw light on the subject of HIimalayan attraction ; for the observations clearly show that the force 'of gravity is less than it should be theoretically at the stations in the vicinity of the Himalayas , and that the difference between theory and practice diminishes the further the station is removed from the HIimalayas . This seems a remarkable confirmation of the Astronomer Royal 's opinion , that the strata of the earth below mountains are less dense than the strata below plains and the bed of the sea . Combining these observations with those which were used by lro . Bailey , including , I believe , all your own , the value of the ellipticity will be -.3 The general result obtained from the thirteen stations of my equatorial and arctic voyages ( 1821-1823 ) was . ' That obtained by Mr. Bailv from Captain Foster 's experi.ments in his equatorial and antarctic voyage ( 18281830 ) was 2-92 . In our Transactions of the present year we have an elaborate and valuable memoir by Mr. Abel " On the Mlanufacture and Compositiou of Gun-cotton , " pointing out the causes of the difference in the analytical results obtained by many of the earlier inquirers into its nature , and confirming its composition as determined by Crum and more fully proved by Hadow , and again stated by the Committee of Chemists who reported on Baron -von Lenk 's Gun-cotton . In pursuing these analytical inquiries , Mr. Abel has tested the methods , both synthetical and analytical , formerly employed , and has devised some modes of analysis of his own . The multiplied and varied experiments which he has made leave no room to doubt the accuracy of his results , though they differ from those of M. Pelouze . With regard to the processes of manufacture , Mr. Abel has proved by experiments , both in the laboratory and on a manufacturing scale , that Baron von Lenk 's method , although it does not at first sight present any important features of novelty , yet unquestionably ensures the attainment of greater uniformity and purity of the product , though Mr. Abel has himself suggested one or two modifications of importance . The most valuable practical result deduced by Mr. Abel from his experiments is , that the instability which has been observed in certain samples of gun-cotton , producing the gradual decomposition of such samples by prolonged keeping , is due to insufficieint purification of the material employed , in consequence of which oxidized products of small quantities of resinous and other foreign substances are formed in the manufacture , and are still retained by the tubular fibre of the cotton . These undergo decomposition , and the change extends to the mass . Many of these impurities are removed by the action of the alkaline bath upon the cotton before treating it with the nitric and sulphuric acids , and others may in great measure be dissolved by a final boiling with a weak alkaline solution . Mr. Abel 's paper is an important contribution ' towards a more complete knowledge than has hitherto obtained of the precautions which are required in the manufacture of gun-cotton in order to diminish still further both the risk of ' accidents , and the liability to injury of the material when not stored , -as it ought invariably to be when no paramount reason requires an exception , ---either under water or in a state of moisture precluding ignition . Since my Address last year little has beenl done in regard to the successful application of gun-cotton to the large ordnance employed in the public service . The desideratum for this purpose may be stated to be a form of cartridge , which with the required velocity of the projectile on quitting the piece , shall have produced an approach to an equality of strain upon every point of the bore , from the instant of ignition to that of the discharge . In the absence of a test of the degree to which this is accomplished , experiments on different forms of the cartridge are necessarily tentative , and the instruction derived from them of comparatively little value . The production of an apparatus by which the actual strain experienced in successive parts of the bore may be recorded , is in fact the first step in a scientific inquiry which should establish the proper relations between the form of the cartridge and the gun . But for the production of an efficient apparatus for this purpose , a chronoscope of greater delicacy and perfection than any we have hitherto possessed in England is indispensable . A chronoscope recently devised by Captain Schultz of the French Artillery appears , as far as can be judged previous to a practical trial , to correspond to these conditions , and to be likely to supply a means of surmounting the difficulty ; it is not improbable that it will be tried in the present year . I proceed to the award of the ATedals . The Copley Medal has been awarded to Professor Jtlius Pliicker , Foreign Member of the Royal Society , for his researches in Analytical Geometry , Magnetism , and Spectral Analysis . To an audience not exclusively mathematical it is obviously impossible to enter into details of researches which deal with geometrical questions of no ordinary difficulty . Amongst these , however , may be indicated , as especially appreciated by those who are interested in the progress of analytical geometry , his theory of the singularities of plane curves as developed in the " Algebriische Curven , " with its six equations connecting them with the order of the curves : the papers on point and line coordinates and on the general use of symbols , may also be noticed as establishing his claim to a position in the department of abstract science which is attained by few even of those who give to it their undivided attention . But Professor Pliicker has high merits in two other widely different fields of researbh , viz. in Magnetism and Spectrology ? and to these I may more freely invite your attention . Shortly after Faraday 's discovery of the sensibility of bodies generally to the action of a magnet and of diamagnetism , Professor Pliicker , in repeating some of Faraday 's experiments , was led to the discovery of magnecrystallic action , -that is , that a crystallized body behaves differently in the magnetic field according to the orientation of certain directions in the crystal . The crystals first examined were optically uniaxal , and it was found that the optic axis was driven into the equatorial position ; ( that is , of course , assuming that the magnecrystallic action is not masked , in consequence of the external form of the body , by the paramagnetic or diamagnctic character of the substance ) . New facts , discovered both by Faraday and by Pliicker himself , led him to a modification of this law , to the effect that the optic axis was impelled , according to the nature of the crystal , either into the equatorial or the axial position . This subject was afterwards followed out by Professor Pliicker into the more complicated cases in which the conditions of crystalline symmetry are such as to leave the crystal optically biaxal ; and after having recognized the insufficiency of a first empirical generalization of the law applicable to crystals of the rhombohedral or pyramidal system , and accordingly to uniaxal crystals , he was led to assimilate a crystal to an assemblage of small ellipsoids , capable of magnetic induction , having for their principal planes the planes of crystalline symmetry where such exist ; and to apply Poisson 's theory . The result of this investigation is contained in an elaborate paper read before the lloyal Society in 1857 , and published in the Philosophical Transactions for the following year . In this paper Professor Pliicker has deduced from theory , and verified by careful experiments , the mathematical laws which regulate the magnecrystallic action . These laws have not necessarily involved in them the somewhat artificial hypothesis respecting the magnetic structure of a crystal from which they were deduced ; and at the close of his memoir Professor Pliicker recognizes the theory of Professor Sir William Thomson , with which he then first became acquainted , as a sound basis on which they might be established . The laws , however , remain identically the same in whichever way they may be derived . Another subject to which Professor Plucker has paid much attention is the curious action of powerful magnets on the luminous , electric discharge in glass tubes containing highly rarefied gas . In this case the luminous discharge is found to be concentrated along certain curved lines or surfaces . He has succeeded in obtaining the mathematical definition of these curved lines or surfaces , by a simple application of the known laws of electromagnetic action , regarding an element of the discharge as the element of an electric current . With regard to the blue negative light , for instance , starting from a point in the negative electrode , he has shown that there are two totally distinct paths , one or other of which , according to circumstances , it may take , going either within the enclosed space along a line of magnetic force , or else along the surface of the glass in what he calls an " epipolic curve , " which is the locus of a point in which the inner surface of the vessel is touched by the line of magnetic force passing through that point . Angstrom appears to have been the first to notice that the spectrum of the electric spark striking between metallic electrodes through air on another gas at ordinary pressures is a compound one , consisting of very bright lines varying with the metal , and others , usually less bright , depending only on the gas . Under the circumstances which presented themselves in his experiments , the latter can frequently be but ill observed ; and the diffused light of a rarefied gas in a wide tube is but faint , and does not form very definite spectra . But Plucker found that by employing tubes which were capillary in one part , brilliant light and definite spectra were obtained in the narrow part . These spectra were observed by him with great care , and were found to be characteristic of the several gases and to indicate their chemical nature , though the gases might be present in such minute quantity as utterly to elude chemical research . It further appeared that compound gases of any kind were instantaneously , or almost instantaneously , decomposed ; at least the spectra they offered were the spectra of their constituents . In a recent memoir , which has only just been published in the Philosophical Transactions , Professor Pliicker has investigated the two totally different spectra frequently afforded by the same elementary substance according as it is submitted to the instantaneous discharge of a Leyden jar charged by an induction-coil , or rendered incandescent by the simple discharge of the coil , or else , in some cases , by ordinary flames . The two spectra show a remarkable difference in character , and are not merely different in the number and position of the lines which they show . Some phenomena which he had previously noticed receive their explanation by this twofold spectrum . This difference of spectra is attributed by Professor Pliicker , with the greatest probability , to a difference in the temperature of the flowing gas when the two are respectively produced . The discovery opens up a new field of research , the exploration of which may throw much light on the correct interpretation of celestial phenomena , especially in relation to the physical condition of nebular and cometary matter . PROFESSOR MILLER , As we have not the pleasure of the presence of Professor Plicker , I must request you , as our Foreign Secretary , to transmit to him this Medal . He will see in it the strongest evidence of the high estimation in which his labours in various lines of scientific research are held in this country ; and I trust you will also express to him the great pleasure which this award gives to his numerous friends here , some of whom have been his fellow-labourers in the same researches . A Royal Medal has been awarded to Mr. William Huggins for his Researches on the Spectra of some of the Chemical Elements , and on the Spectra of certain of the Heavenly Bodies ; and especially for his Researches on the Spectra of the Nebulae , published in the Philosophical Transactions . The researches on the stellar spectra referred to in this award were made by Mr. Huggins conjointly with our highly valued Treasurer and senior Vice-President , Dr. William Allen M[iller . The position of the latter as one of the officers of the Society and a member of its Council has forbidden the consideration of his claims to share in the honours which the Society can bestow ; and in conformity with the spirit of this , our " 'self-denying ordinance , " it would be my duty to dwell altogether on the merits of our Medallist , if , indeed , it were possible in this case to separate between the merits of the two authors of the conjoint research . This is scarcely possible , and I must be excused , therefore , if I sometimes speak of them together . Fraunhofer , Lamont , and others have at various times attempted to observe the spectra of the planets and fixed stars ; yet , though provided with powerful instruments , they obtained no important results . Mr. I-uggins and Dr. 3Tiller devised a method of seeking in the spectra of the fixed stars that evidence of the existence in them of known elementary substances which had been obtained in the case of the sun by Bunsen and Kirchhoff . A preliminary investigation of the spectra of the more important of the terrestrial chemical elements , and their direct comparison with the lines in the spectrum of common air , was undertaken by Mr. Huggins , with the view of providing a standard scale of comparison , which , unlike the solar spectrum , would be always at hand when stellar observations are possible . This was in itself a work of enormous labour ; and when completed , the spectra of the fixed stars , including those of some double stars of contrasted colours , were attacked by the two investigators ; and by a happy adaptation of comparatively moderate instrumental means , and unwearied diligence in observing and determining by micrometrical measurements the positions of objects that all but elude human vision , their researches have been rewarded by the most complete success . The spectra of the stars were compared by a method of simultaneous observation with the spectra of many of the terrestrial elements . It is upon this method of direct conmparison that the trustworthiness of the results obtained chiefly depends , and in this respect these observations stand alone . [ In 1815 Fraunhofer recognized several of the solar lines in the spectra of the Moon , Venus , and five of the fixed stars . In 1862 Donati published diagrams of three or four lines in fifteen stars . Recently Secchi , Rutherford , and the Astronomer Royal have given diagrams of the positions , obtained by measurement only , of a few strong lines in several stars . ] Eighteen stars have afforded spectra containing lines coinciding with the lines of many of the elementary substances . In thirty-seven more the spectra are full of lines which have not yet been fully compared . On extending these researches to the Nebulae , Mr. Eiuggins made the most unexpected discovery that the spectra of certain of these bodies are discontinuous , consisting of bright lines only , whence he drew the conclusion that " in place of an incandescent solid or liquid body transmitting light of all refrangibilities through an atmosphere which intercepts by absorption a certain number of them-such as our sun appears to be we must probably regard these objects , or at least their photo-surfaces , as enormous masses of luminous gas or vapour . For it is alone from matter in a gaseous state that light consisting of certain definite refrangibilities only , as is the case with the light of these nebulae , is known to be emitted . " During the last two years Mr. Huggins has examined the spectra of more than sixty nebula and clusters . This examination shows that these remarkable bodies may be divided into two great groups : viz. 1st , true or gaseous nebulae , which furnish a discontinuous spectrum , consisting of two or three bright lines only ; and 2nd , what we may distinguish as spurious nebule , or nebulous matter with clusters , which give a spectrum apparently continuous . Of the latter group a large proportion show signs of resolvability into clusters by telescopes of high power . In the present year also Mr. Huggins has made a remarkable observation upon the small comet , known as comet No. 1 , 1866 . He ascertained that the minute nucleus gave a gaseous or discontinuous spectrum ; whilst the spectrum of the coma , as though formed by suspended particles which reflected solar light , gave a continuous spectrum . Since the publication of these results by Mr. Iuggins , our investigators have examined with great care the spectrum of the star which is either new or has greatly increased in brilliancy in Corona borealis , and have found that that star has a spectrum of absorption , and also a gaseous spectrum of which hydrogen is probably the source . They have also connected , in one instance at least , the change in a variable star with a variation in its spectrum . Discoveries like these , which acquaint us not only with the constituents of the heavenly bodies but also with their state of aggregation , are of the nature of those which occur only once in the course of centuries , -like the discovery of the satellites of planets , of solar spots , or of double stars , and have the strongest possible claim on the Royal Society for such honours as the Society has at its disposal . AIR . -IUGGINS , It gives me the greatest pleasure to present you with this Medal : a testimonial of the very high estimation in which your successful labours ( conjointly with Dr. Miller ) are held by the Society , which has the satisfaction of regarding you as one of its most distinguished Members . You are at an age at which you may reasonably indulge in the prospect of having a long career before you ; yet , however long , it will scarcely exhaust the noble field of research which you have opened for yourself , and which is one in which you are quite sure to be accompanied by the sympathy of men of science throughout the world . A Royal Medal has been awarded to Mr. William Kitchen Parker for his researches in Comparative Osteology , and more especially on the Anatomy of the Skull , as contained in papers published in the Transactions of the Zoological Society and the Philosophical Transactions . Mr."Parker has for several years past made investigations of great extent and distinguished merit among the Foraminifera , the results of which are embodied in Memoirs published by him from 1859 to 1865 , in conjunction with Professor Rupert Jones and with Dr. Carpenter in the Annals of Natural Iistory , the publications of the Ray Society , and the Philosophical Transactions . The award of a Royal Medal to Mr. Parker has been based , however , not so much on his work in this department of zoology as on his labours in a very different and much more difficult branch of anatomy , Vertebrate Osteology . In 1860 Mr. Parker published a memoir " On the Osteology of Balceniceps Rex , " and in 1862 another " On the Osteology of the Gallinaceous Birds and Tinamous , " in the Transactions of the Zoological Society ; while a third still more important memoir , on the " Skull of the Ostrich Tribe , " was read before the the Royal Society in March 1865 , and is now published in the Philosophical Transactions . In these elaborate andbeautifully illustrated memoirs , Mr. Parker has not only displayed an extraordinary acquaintance with the details of Osteology , but has shown powers of anatomical investigation of a high order , and has made important contributions towards the establishment of the true theory of the vertebrate skull . M* R. WILLIAM KITCHEN PARKER , I present you with this Medal in testimony of the high esteem in which your investigations are held by those of our body who are qualified to appreciate them , and who look at once with approval and with expectation at the increased and still increasing interest of the communications contributed by you to our Transactions . The Council have awarded the Rumford Medal to M. Armand IHippolyte Louis Fizeau for his Optical Researches , and especially for his Investigations into the Effect of Heat on the Refractive Power of Transparent Bodies . In 1849 M. Fizeau rose into celebrity as the experimenter who first succeeded in measuring the velocity of light by observations limited to objects on the surface of the earth . He noted the time required for the passage of light from the place of the observer to a mirror , normal to the path of the light , 8633 metres distant , and back again , by means of a wheel having 720 teeth revolving rapidly . When the wheel made 126 revolutions in 10 seconds , the light that had passed through the notch between two teeth towards the mirror was stopped completely on its return , after reflexion , by the second of the two teeth ; showing that the light had travelled 17,266 metres while the wheel had revolved through half the angle subtended at its centre by the distance between the summits of two adjacent teeth , or -rrnT second . In 1859 he wrote a remarkable memoir , " Sir un experience qui parait demontrer que le mouvement des corps change la vitesse avec laquelle la iumire se propage dans leur int6rieur . " I-his " Methode propre a rechercher si l'azimuth de polarisation du rayon refracte est influence par le mouvement du corps refringent " ( 1860 ) involves such complicated arrangements that great hesitation was felt about accepting the results . But whoever has seen his experiments on the expansion and the alteration of the refrangibility of bodies when heated , is not disposed to question any conclusions regarded by Fizeau himself as well founded . In 1862 he published " Recherches sir les modifications que subit la vitesse de la lumi & re dans le verre et plusieurs autre corps solides sous l'influence de la ehaleur , " the first of a series of memoirs on the change of dimensions and refractive powers of various kinds of glass , and many crystallized substances . On the 23rd of May , 1864 , he read before the Institut " ' Recherches sir la dilatation et la double refraction du cristal de roche echaiff ; " and on the 21st and 28th of May , 1866 , " ( M6 oires sir la dilatation des corps solides par la chaleur . " In these observations he has availed himself of the possibility of forming Newton 's rings with the monochromatic sodium light when one of the interfering rays is 52,205 waves in advance of the other , a fact which , conjointly with M. Foucault , he announced in 1849 . Using the length of a wave of sodium light ( 0'0005888 millimetre ) as the standard of measure , the position of a ring being observable to within I-i of the distance between two consecutive rings , the variation of the distance between two surfaces producing the Newton 's rings can be measured to within -1s T millimetre . A plate of the substance to be experimented on ( let us suppose it to be fluor ) , usually from 10 to 15 millimetres thick , bounded by parallel plane surfaces , rests upon the platform of a metal tripod ( the metal was steel in the earlier observations , platinum with -T & of iridium in the later ) . The feet of the tripod are screws of equal lengths terminating above in obtuse points . On these points , at a distance of about gmillimetre above the upper surface of the fluor , rests a plate of glass . By counting the number of rings or bands that pass over a mark on the upper surface of the fluor during a given change of temperature , the corresponding variation of distance between the lower surface of the glass and the upper surface of the fuor is given , and the expansion of the metal being known by a similar process , the expainsion of the fluor is found . The Newton 's rings formed between the two surfaces of the fluor depend upon its thickness and its refractive power . The number of rings that pass over the mark on the fluor during a given change of temperature bei ng observed , and its expansion having been found by the preceding observation , the change of its refi'active power due to the change of temperature becomes known . , In this way M. Fizeau obtained several very unexpected results . Of these a few may be noticed . The indices of refraction of most substances were found either to increase or to remain unaltered with an increase of temperature , but in fluor the index of refraction diminishes with an increase of temperature . Diamond , cuprite , and beryl have a maximum density , like water-diamond at -420 ? 3 C. , cuprite at -4 ? '3 , and beryl at -4 ? '2 . Beryl , when heated , unlike calcite , contracts in the direction of its axis , and expands in a direction making right angles with the axis . Quartz , rutile , cassiterite , spartalite , corundum , and hematite were found to expand in every direction when heated ; but in each case the expansion in the direction of the principal axis was different from the expansion in a direction at right angles to the principal axis . M. Fizeau is also the author of many other important researches-on Moser 's images , on photography , on the automatic engraving of photographic images on copper , on the interference of rays of heat , on electricity and the velocity of its propagation , and on the position of the plane of polarization of light reflected from striated metallic surfaces . PROFESSOR MILLER , I have to request you to transmit this Medal to Monsieur Fizeau , in testimony of our interest in his researches and our high respect for his merits , which you have yourself been especially instrumental in placing in a clear light before the Council . On the motion of Vice-Chancellor Sir W. Page Wood , seconded by Mr. Hog , it was resolved , -"That the thanks of the Society be returned to the President for his Address , and that he be requested to allow it to be printed . " The Statutes relating to the election of Council and Officers having been read , and Mr. Balfour Stewart and Mr. C. V. Walker having been , with the consent of the Society , nominated Scrutators , the votes of the Fellows present were collected ; and the following were declared duly elected as Council and Officers for the ensuing year : President.-Lieut.-General Edward Sabine , Il . A. , D.C.L. , LL. D. Treasurer.-William Allen Miller , 3LD . , LL. D. Seererie . J William Sharpey , M.D. , LL. D. . George Gabriel Stokes , Esq. , M.A. , D.C.L. , LL. D. Foreign Secretary.-Professor William Hallows Miller , M.A. , LL. D. Other iMember s of the Council.-Lionel Smith Beale , Esq. , M.D. ; William Bowman , Esq. ; Commander F. J. Owen Evans , R.N. ; Edward Frankland , Esq. , Ph. D. ; John HIall Gladstone , Esq. , Ph. D. ; William Robert Grove , Esq. , M.A. , Q.C. ; William Huggins , Esq. ; Thomas Henry Huxley Esq. , LL. D. ; William Lassell , Esq. ; Professor Andrew Crombie Ramsay , LL. D. ; Colonel William James Smythe , R.A. ; William Spottiswoode , Esq. , MA . ; Thomas Thomson , M.D. ; William Tite , Esq. ; Vice-Chancellor Sir W. P. Wood , D.C.L. ; The Lord Wrottesley , MI . A. , D.C.L. The thanks of the Society were voted to the Scrutators . RecciPts and Payments of the Royal Society between Decemnber 1 , 1865 , and November 30 , 1866 . ? s. d. Balances on hand ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . . 15 9 Annual Subscriptions , Admission Fees , and Compositions ... 1697 16 0 ents ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 253 18 0 Dividends ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 1541 3 Ditto , Trust Funds ... ... ... ... ... ... ... ... ... ... ... ... ... ... 23 06 Sale of Transactions , Proceedings , &c. ... ... ... . 383 02 Repayiments ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . . 96 30 Prof. Sylvester , repaid to Donation Fund ... ... ... ... ... ... ... 25 00 2-'4295 16 11\~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~--~--~ ? - ? r ? .~ ? s. d. Balance due to Banl kers ... ... ... ... ... ... ... ... ... ... ... ... . 135 7 10 Salaries , Wages , and Pension ... ... ... ... ... ... ... ... ... ... ... . . 1031 12 0 The Scientific Catalogue ... ... ... ... ... ... ... ... ... ... ... ... 178 17 6 Books for the Library and Binding ... ... ... ... ... ... ... ... ... 33 16 6 Printing Transactions and Proceedings , Paper , Binding , Engraving , and Lithography ... ... ... ... ... ... ... ... ... ... ... 1334 14 8 General Expenses ( as per Table subjoined ) ... ... ... ... ... ... 483 92 Donation Fund ... ... ... ... ... ... ... ... ... ... ... ... ... 80 00 Wintringham Fund.5 ... ... ... ... ... ... ... ... ... ... . 35 50 Copley Medal Fundcl ... ... ... ... ... ... ... ... ... ... ... 4 15 0i J. Clerk Maxwell , Bakerian Lecture ... ... ... ... 4079 Rev. Dr. Stebbing , Fairchild Lecture ... ... ... ... 2 18 9 Croonian Lecture ( Poor of St. James 's Parish ) 2 19 Oj 3629 15 5 Balance at Bank ... ... ... ... ... ... ... ... ... ... ... ... ... . . 638 81 Balance of Catalogue Account ... ... ... ... ... ... ... ... ... ... ... ... 18 19 9 , Petty Cash Account ... ... ... ... ... ... ... ... ... ... ... ... ... 8 13 8 ? 4295 16 11 WILL LEN ILLIAM ALE LER , Treasurer . Esetaes and Property of the Royal Society , inchding Trust FZunds . Estate at Mablethorpe , Lincolnshire ( 55 A. 2 R. 2 P. ) , ? 126 Os . Od . per annum . Estate at Acton , Middlesex ( 34 A. 3 I. 11 p. ) , 2110 Os . Od . per annum . Fee farm near Lewes , Sussex , rent -19 4s . per annum . One-fifth of the clear rent of an estate at Lambeth HIill , from the College of Physicians , ? 3 per annum . ? 14,000 Reduced 3 per Cent. Annuities . ? 28,969 15s . 7d . Consolidated Bank Annuities . ? 513 9s . 8d . New 2 ' per Cent. Stock-Bakerian and Copley iedal Fund . 0 < 0 tr 34 Dr. I ScientZfi BRelief Fund . Investments up to July 1865 , New 3 per Cent. Annuities ... ... ... ... ... ... ... ... ... 6052 17 8 ? 6052 17 8 ? s. . d " Balance ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 181 10 8 By Grants Subscriptions 13 13 0 Balance Dividends ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 178 11 2 ? 373 14 10 Statement of Income and Expenditure ( apart from Trust Funds ) during the Year encling November 30 , 1866 . 'f ' 7 Annual Subscriptions ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... Admission Fees ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... Compositions ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . . R ents ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... Dividends on Stock ( exclusive of Trust Funds ) ... ... ... ... , on Stevenson Bequest ... ... ... ... ... ... ... ... ... ... Sale of Transactions , Proceedings , &c. ... ... ... ... ... ... ... . . Chemical Society , for Proceedings , 1865-66 ... ... ... ... . . Chemical Society , Tea Expenses ... ... ... ... . 16 78 Linnean Society , Tea Expenses ... ... ... ... ... 16 7 8J Geographical Society , Gas at Evening 84 81 Meetings ... ... ... ... ... ... ... ... ... ... . . CambridgeLocalExamination Committee , Gas 480 St. George 's Rifles-Gas ... ... ... ... ... ... ... ... 15 O 1111 16 0 170 00 416 00 253 18 0 997 3 10 544 65 383 02 50 00 32 15 4 13 78 Income available for the Year ending Nov. 30 , 1866 ... ... 3972 75 Expenditure in the Year ending Nov. 30 , 1866 ... ... ... . . 3364 9 10 > Excess of Income over Expenditure in the Year ending ? 607 17 7 Nov. 30 , 1866 ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... Cr . ? s. d. 160 00 213 14 10 ? 373 14 10 - ? 9 s. d. Salaries , Wages , and Pension ... ... ... ... ... ... ... ... ... ... ... 1031 12 0 The Scientific Catalogue ... ... ... ... ... ... ... ... ... ... ... ... ... . 178 17 Books for the Library ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 197 50 Binding ditto ... ... ... ... ... ... ... ... ... ... ... ... .138 11 6 Printing Transactions , Part II . 1865 , and 350 18 9 Part I. 1866 ... ... ... ... ... ... ... ... ... ... ... 18 Ditto Proceedings , Nos. 78-86 ... ... ... ... ... 276 14 9 Ditto Miscellaneous ... ... ... ... ... ... ... ... ... ... 76 60 1334 14 8 Paper for Transactions and Proceedings ... 228 16 5 Binding and Stitching ditto ... ... ... ... ... ... ... 78 25 Engraving and Lithography ... ... ... ... ... ... 323 16 4 Upholstery , Cleaning , and Repairs ... ... ... ... ... ... ... ... ... 48 88 Miscellaneous Expenses ... ... ... ... ... ... ... ... ... ... ... ... ... . . 39 90 Coal , Lighting , and Gas-fittings ... ... ... ... ... ... ... ... . . 136 69 Tea Expenses ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 49 21 Fire Insurance ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 28 11 6 Donation:-Mablethorpe Schools ... ... ... ... ... ... ... ... ... ... 220 Taxes ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 8 19 2 Taxes ... . 8 19 2 Law Expenses ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . . 126 7 10 Advertising ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 9 15 6 Postage , Parcels , and Petty Charges ... ... ... ... ... ... ... ... ... 34 6 8 ? 3364 9 10 WILLIAM ALLEN MILLER , Treasurer . o c-1I I o. . The following Table shows the progress and present state of the Society with respect to the number of Fellows : Patron Having Paying Paying and Foreign . com ? 2 12s . ? 4 Total . Royal . pounded . annually . annually . November 30 , 1865 . 6 47 309 3 274 639 Since elected ... ... ... . . +3 +6 ... ... +9 +-18 Since readmitted ... ... ... ... ... ... . 1 +1 Since compounded ... ... ... ... ... ... . . -1 Since deceased ... . -1 1 -14 . -15 -31 Since defaulter ... ... ... ... ... ... ... ... ... . -1 -1 November 30 , 1866 . 5 49 302 3 267 626

112637

3701662

Discussion of Tide-Observations at Bristol. [Abstract]

289

290

Proceedings of the Royal Society of London

T. G. Bunt

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112637

http://www.jstor.org/stable/112637

Meteorology

Tables

Meteorology

I. " Discussion of Tide-Observations at Bristol . " By T. G. BUNT , Esq. Communicated by the Astronomer Royal . Received October 24 , 1866 . ( Abstract . ) This Paper contains the results of a Discussion of about 19,000 observations of Times and Heights of Iigh Water at Bristol , for the purpose of obtaining the Empirical Laws of the Diurnal Inequalities of the Times and HIeights , and of the Solar Inequality of the Times , of the tides at that port . Curves on Diagrams which accompany the Paper exhibit the results . The Observations were taken by a Self-registering Tide-Gauge , the Clock of which has from the first been regulated by transit observation . The Diurnal Inequalities of the tides at Bristol are not large , that of time averaging only 2 minutes ( earlier or later ) , and that of height 2k inches ( greater or less ) . Although it was stated by Sir JohnW . Lubbock ( in 1839 ) that the diurnal inequality in time is too minute to be observed on our coasts , the slightest examination of the Diagram ( No. 4 ) will be sufficient to show that this remark is inapplicable to Bristol . On this diagram are laid down the times and heights of tide registered there during six months of the year 1865 . In consequence of the tranquil state of the weather , the agreement of the observed with the predicted times was unusually close ; the average error in time , during the six months , being only 2minutes , and for six weeks less than 1'9 minute . The diurnal inequality , of time as well as of height , is throughout the diagram most conspicuous ; and the agreement of the calculated with the observed inequality close and satisfactory . For each of the Diurnal Inequalities , the residues , or errors , of the calculated Times and Heights were arranged for every half month , and for each of the twenty-four hours of Lunar transit , making ( 24 x 24 = ) 576 Groups . The averages of these , laid down in Curves , are shown in Diagrams No. 1 and 2 . Diagram No 3 shows the Solar Inequality of Time , obtained in a similar manner , together with curves of the separate effects of the Solar Parallax and Solar Declimation . A sheet from the Tide-Gauge Cylinder has also been sent , as a specimen of the regularity of the registered Curves in tranquil weather .

112638

3701662

On the Heating of a Disk by Rapid Rotation in vacuo

290

299

Proceedings of the Royal Society of London

Balfour Stewart|P. G. Tait

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0068

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112638

10.1098/rspl.1866.0068

http://www.jstor.org/stable/112638

Thermodynamics

Fluid Dynamics

Thermodynamics

II . " On the Heating of a Disk by rapid Rotation in vacuo . " By BALPOUR STEWART M.A. , F.R.S. , and P. G. TAIT , M.A. ( Continuation of a Paper read before the Royal Society on June 15 , 1865 , and published in the 'Proceedings . ' ) Received October 30 , 1866 . 16 . The apparatus and certain preliminary experiments having been described in the previous paper , the authors now proceed to relate what further experiments have been made . In the preliminary experiments it was conclusively shown ( art . 8 ) that the effect on the pile caused by rotation of the disk was due to radiant heat , and also ( art . 9 ) that this effect was not due to the heating of the rock-salt , which in most of the experiments was placed before the mouth of the cone . It was also rendered probable that the effect was not due to radiation from heated air , by the two following considerations:(1 ) Because in order that nearly dry air of such a tenuity might give such a radiation it would require to be heated enormously . ( 2 ) Because when the lampblack was removed from the aluminium disk , leaving it a roughl metallic surface , the indication afforded by the galvanometer was reduced to about one-fourth of the amount with the blackened disk . The following observations tend to strengthen this proof:(3 ) The heating effect is the same in hydrogen or in coal-gas as in air , although there is no question that the absorptive , and therefore the radiative power of coal-gas is much greater than that of air . This is shown by the following sets of experiments , which were made with the blackened aluminium disk insulated with ebonite , and with rock-salt in the cone . , t Ijv Z ? 5 Heat indication . |oJ | . ** '3 J_ L__ _____ Natulre Tensio ? , i blackened aluminiumn disk than from an unblackened one does not prove that this heating effect may not be due to air , since the blackened surface may be imagined to lay hold of the air more than the metallic one . But the following sets of experiments prove that the heating effect of the aluminiium disk with both sides blackened is the same as when only one side is blackened. . 4 . , . 0 §§. . OA ' ? e X. 2 30 20 0'9 1-1 Disk blackened on one side . XIII . 3 30 20 0'8 0-4 Disk blackened on both sides . It would therefore appear to be proved that in these experiments the heating effect is due to the increased temperature of the disk . 17 . Before proceeding further it may be advisable to detail some experiments made with an ebonite disk - , inch thick . In these experiments care was taken that the ebonite should have the same temperature throughout its thickness , so that there might be no flow of heat from the interior to the surface , or vice versa . The experiments were made with rock-salt in the cone . , ... ' . ; * | |.atu1ri r Tension 4| 4 . 4-4^ tl e 1i '* Nature of of gas , in o oD gas . inches . ff XIV . 3 30 20 32 air 11 XV . 1 30 20 30 air 0-26 XVI . 1 30 20 31 air 11 XVII . 2 30 20 28-5 air 0-26 XVIII . 2 30 20 28-5 air 0-25 XIX . 3 30 20 29 hydrogen 0-25 90 From these experiments it may be taken for granted that the heat indication given by an ebonite disk is , like that from an aluminium disk , independent both of the density and chemical constitution of the residual gas . It is also highly probable that the unknown cause of the heating effect is the same for both disks . 18 . To return now to the aluminium disk , it may be shown that the heating of this disk is not caused by revolution under the earth 's magnetic force ; for ( 1 ) the following calculation , kindly furnished by Professor Maxwell , shows that the heating effect due to this cause would , for the aluminium disk 1 of an inch in thickness , amount , under the circumstances of rotation , only to f-i -1 of a degree Fahr. , whereas the observed effect is more than half a degree . An ellipsoid , semiaxes a , b , c , revolves about the axis c with velocity w , 22 in a uniform magnetic field . To find its electrical state at a given instant . At the given instant let the axes of x , y , z coincide with a , b , c ; then using the notation in the paper on the Electromagnetic field * , P-t=wyx-a=-P , Q=PWYY--y=qP , i= --a , ( / 3y+ax)-a ? PQ electromotive force , ary magnetic intensity,.b electric tension , e=coefficient of magnetic induction =I for everything but iron , p , gq , r electric currents , p=resistance of cubic unit of volume . The condition of the currents being confined to the ellipsoid , is a2+ 62+'= Solving , we get p( a'2a pw 62u / ax pie \ 2Pp a-}-q2 p62 qp ac 2 C2 62C2 I= 2y('2 +1 ' ? y')(^ @+a 6+c2 C ) + C. This is the complete solution . The heat ( measured as energy ) produced in unit of volume in unit of time is p(p2 +q2 + 22)* The whole heat produced in the ellipsoid in unit of time is 47r f2 aac3 a / a ? 22 } 1l , p { a " W+2 ++ c ' 4r It2 alea If a=b , this is p a+e ( a2+p2 ) . If c is small compared with a , it becomes 47r A2 -5 p-2-a2C3(2 -_/ 2- ) . If the axis is horizontal , a 2+ -3IP2 sin2 0+ V2 , where H=horizontal magnetic force , and V=vertical magnetic force , and 0=angle between the axis of rotation and the magnetic meridian , a=radius and c half the thickness , w= 27rn , where n denotes the revolutions per second ; ip= 1 ; p is the resistance of unit length and unit section . Now , the resistance of 1 metre long and 1 millimetre diameter =4P10G-=00375 X 107 7r r 32 for aluminium in metrical units by Matthiessen , or-= p is the same for metrical and for British measure . At Kew horizontal force=3'81 , dip 68 ? '10 ; 0=90 ? in the experiments.a . a2+2= 104-8 British measure . The revolving body is not an ellipsoid but a cylinder , equally thick 15 throughout ; to correct for this we shall put -2 c for c3 . We get for the energy converted into heat by electrical action per second 12'91 in grain-foot-second measure . Now 772-= energy required to raise 1 grain of water 1 ? Fahlr . 70,000 The disk =-- ' 22 grain of water,. . energy corresponding to 1§ 32'2 = 772 x -16 x 15400 , 12'91 12'91 or rise of temperature per second= 1540x 15400= 23716000 degree Fahr. or about 61270 degree in 30 seconds . This is when the heat is uniformly distributed through the thickness of the disk , which it will be in less than thirty seconds . If there were no conduction , the rise of temperature at the surface would be about twice the value found above . ( 2 ) It would appear from the above formula that the heating effect due to this cause should increase with the thickness of the disk . The following experiments show that , on the contrary , the heating effect , as regards temperature , diminishes as the thickness of the disk increases . 0 00 0 . _"o~ ( 1 , Z P- : C ) , ~ . Pp0 000 804 4-ec ~0 0C C 0-00 XIII . 3 30 20 0-8 0-4 Aluminium disk nl inch thick . XX . 3 30 21 1-7 04 Aluminium disk l inch thick . ( 3 ) The heat indication afforded by an ebonite disk is against the conclusion that this effect is due to rotation under the earth 's magnetic force . It would therefore appear to be proved that in these experiments the increased temperature of the aluminium disk is not due to rotation under the earth 's magnetic force . 19 . It might perhaps be said that the heating of the disk may be due to heat conducted from the bearings into the disk and then distributed outwards ; and this conjecture will require to be examined , since the bearings are , no doubt , heated by friction during the motion . This heating effect on the bearings was measured by means of a very delicate thermometer , which was inserted into a small hole in the bush through which oil is supplied to the spindle , and made to be in metallic contact with the sides of this hole ; the mean of three observations made the heating effect at the spindle due to rotation to be 4 ? Fahr. In the next place , the aluminium disk , separated from its metallic spindle by the ebonite washer , and in every respect the same as when made to rotate , had its spindle heated artificially by a mercury bath , generally at least 40 ? Fahr. above the previous temperature . After the lapse of two minutes the effect upon the pile was hardly perceptible-not more than five divisions . 1 ) It would appear from this experiment that the heating effect ob served in rotation cannot be due to heat conducted from the bearings through the ebonite washer , since a temperature difference between the bearings and the disk ten times greater than that produced by rotation causes a heating effect at least six times less than that caused by rotation in a somewhat less time . ( 2 ) The ebonite washer used to prevent the heat of the bearings from reaching the aluminium disk , is a cylindrical disk , its thickness being twotenths of an inch , and the area of one of its faces 3 15 square inches . It is shielded behind by a brass disk , of similar size , which brass disk being near the bearings , and metallically connected with them , wte may suppose to have the same temperature as the bearings . Thus one face of the ebonite washer is in contact with brass , having the temperature of the bearings , while the other is in contact with the aluminium disk . Supposing that this washer , used to protect the aluminium disk from the heat of the bearings , was of iron instead of being of ebonite , we can calculate approximately from Principal Forbes 's determinations of the absolute conductivity of this metal , how much heat would be conducted across the washer during the experiment . According to these observations , if a cube of iron whose side is one foot , have one of its faces kept permanently at a temperature 1 ? C. higher than the opposite face , the quantity of heat conducted across in one minute will be '011 unit nearly , a unit denoting the amount of heat required to raise a cubic foot of water 1 ? C. Since in these observations both the temperature difference and the unit are expressed in the same thermometric degrees , we may , if we choose , substitute degrees Fahr. for degrees Centigrade in the above expression for conductivity . Now , if we assume as an approximation that during the whole experiment of rotation the heat conducted across such a washer is the same as if for one minute the temperature difference between both sides of the washer were kept at 2 ? Fahr. , and if we make allowance for the surface and for the thickness of the washer , we obtain the following expression as approximately representing the heat conducted across the washer during the experiment , 3'15 12 Heat=--01 x2xX =302 T08 unit nearly , 144 -2 where the first factor is on account of the double temperature difference , the second on accountt of the surface , and the third on account of the thickness . But a unit of heat in the above expression denotes the amount necessary to raise a cubic foot of water ( or nearly 1000 ounces ) 1 ? Fahr. Now the weight of the disk is 10*5 ounces , and its specific heat is 0-22 . Hence the above amount of heat will raise the disk 1000 1 *028 x x10 -= 12 ? Fahr. in temperature . 10'5 '22 Hence we see that if the material of the washer had been of the metal bismuth , of which the conductivity is 7 times less than that of iron , and if we suppose the circumstances of the experiment to be equivalent to a temperature difference of 2 ? Fahr. between the two sides of the washer lasting for one minute , then the quantity of heat conducted across the washer will be a little greater than that observed . But the conductivity of ebonite is no doubt very much less than that of bismuth , and therefore on this account we cannot suppose that the heating effect observed is due to conduction . ( 3 ) In this investigation no account has been taken of the unequal distribution of temperature from the centre to the circumference of the disk , the tendency of which would be to diminish the effect upon the pile ( which was directed to the circumference of the disk ) of the heat passing through the washer ; and indeed , when this element is taken into account , it is not surprising to find , as was actually the case , that in some preliminary experiments , where the disk was metallically connected with the spindle , the effect was not greater than with the ebonite washer . ( 4 ) The short time in which the effect attains its maximum value is against the supposition that it is caused by conduction from the bearings . ( 5 ) The fact that ( as we shall afterwards see ) the temperature effect in three aluminium disks of different thicknesses is inversely proportional to the thickness , is also against this supposition . ( 6 ) And so is the fact that a heat-effect obeying apparently the same laws , holds for an ebonite disk in which there is but a very feeble conduction . On the whole , therefore , we cannot suppose this effect to be due to conduction , or at least we must conclude that the effect of conduction constitutes only an exceedingly small fraction of that observed . 20 . Itwas suggested to the authors by Professor Stokes and by Mr. Grove , that the effect might be due to vibrations of the disk , the energy of which , owing to the viscosity of the disk for such vibrations , might ultimately become converted into heat ; and it is necessary to examine this question . ( 1 ) The thickest aluminium disk was found to be out of truth not more than -015 inch on each side . Hence , the thickness of this disk being *05 inch , when turned with moderate rapidity , its apparent thickness should be -015 + 05 + 01 == 08 ; and experiment showed that when turned very fast , its apparent thickness was no greater . The greatest possible range of vibrations of the disk at its circumference could not , therefore , be more than '015 inch on either side of the position of rest . Again , it was ascertained by means of the note given by this disk , that it vibrates about 250 times per second . Let us suppose the whole mass to have the same range of excursion ( this will of course increase the result ) , the equation of vibration ( not allowing for loss by viscosity ) is x='015 cos nt and also time of vibration 2rw 1 -nz 250 ' Hence n=500 x314-=1570 , say , cdx in . in..* " =--'015x 15 70 sin nt,. . greatest velocity =23'55 , or say 2 feet per second . IHence the energy of this motion in foot pounds , =weight of disk in pounds x ' 2g =weight of disk in pounds through -Lof a foot . But an approximate experiment performed by causing the disk to ring , and noticing how long the sound lasted , would seem to show that probably the energy of vibration of the disk diminishes at first , and therefore constantly ( if it is maintained ) at the rate of the whole in 3 seconds . Hence in 30 seconds it loses 10 times as much as the whole ; that is to say , in 30 seconds the heat produced cannot be greater than that due to the energy produced by the disk falling under gravity through l-o of a foot . Reducing this to its heat-equivalent , the greatest possible heat effect due to vibration during 30 seconds rapid turning will be less than 10 I11 Far . ^X ---XO Fahlar_ 16 772 x22 272 which is a very small fraction of the effect observed . ( 2 ) The thin aluminium disk was out of truth about *02 inch on each side . Its note of vibration was as nearly as possible one octave lower than that of the thick disk , while its coefficient of viscosity was somewhat greater , say in the proportion of 3 to 2 , than that of the thick disk . On the supposition that the heat generated is due to vibration , if we call the heat generated during 30 seconds in the thick disk =1 , then that generated during the same time in the thin disk ought to be / .027 3X I xx- , where the first factor is on account of difference of time of vibration , the second on account of difference of range , the third on account of difference of mass , and the fourth on account of difference of viscosity . But the heating effect ( as far as quantity of heat is concerned ) produced in the thin disk is as nearly as possible the same as that produced in the thick disk . This fact is therefore against the hypothesis that the heating effect is due to vibration . ( 3 ) In order to estimate the effect ( if any ) of want of truth in the disk , the thick aluminium disk was purposely put out of truth about 3k times srlv alrlrh+~lriLLl~+Ll l*IJ+~VI+~ lUrVIL13( CCV ldL V ~iU~~ C~JUt ? t ; its usual amount ; but the heating effect was as nearly as possible the same in both cases , being 32 divisions of the scale in both . On all these grounds it would appear that the heating effect cannot be due to vibration of the disk . 21 . It is hardly necessary to mention that the heating effect cannot be due to radiation and convection from the wheelwork , which is no doubt slightly heated during the experiment , for the mass of this metallic matter is so great , that we cannot imagine it to be heated more than 10 Fahr. Now the radiation from this against the back of the disk may certainly be neglected , while the convection must be very small , since in the experiments the pressure of the air was very small . Besides , the heating effect , as will be seen shortly , was found to be independent of the pressure . 22 . It has thus been shown that the disk is heated during the experiment , and that this heating effect(1 ) Is not due to rotation under the earth 's magnetic force ; ( 2 ) Is not due to conduction of heat from the bearings ; ( 3 ) Nor to radiation or convection from the wheelwork ; ( 4 ) Nor to vibrations of the disk . And in view of the large and constant nature of this heating effect it may be asserted that it cannot be sensibly due , either to one of these causes singly , or to their combined effect . 23 . It will now be sliown that the heating effect is independent both of the density and chemical constitution of the residual air and vapour around the disk . In art . 16 , if we compare together the 7th , 8th , 9th , 10th , 11th , and 12th sets of experiments , we shall see that the heating effect was sensibly the same , whether the residual gas was atmospheric air , or hydrogen or coal-gas . As hydrogen diffuses very quickly , it might perhaps be supposed that when heated by rotation it might find access to the pile through the rocksalt cover more easily than heated atmospheric air , so that while the whole effect might appear the same in hydrogen as in air , yet only part of that in hydrogen might be due to radiant heat , the remainder being due to heated gas which had obtained access to the pile . This was , however , disproved by an experiment , which showed that by'blackening the interior of the cone , the effect upon the pile was just as much diminished in a hydrogen vacuum as in an air vacuum ; and hence in both cases the whole effect is due to radiant heat . But , besides the residual gas , it may with truth be supposed that there is always more or less of aqueous vapour , and also a little of the vapour of oil , and perhaps of the vapour of mercury in the receiver . As regards the hygrometric state of the residual air and its influence on the disk , this would appear to be of the following nature:(1 ) When the vacuum has just been made , there is generally a hygrometric difference between the air and the surface of the disk , on account of which there is a strictly temporary effect , either in the direction of heat or cold , at the surface of the disk , owing probably to condensation or evaporation of small quantities of aqueous vapour ; but this effect disappears the moment the motion is stopped , leaving behind the permanent effect apparently unaltered . ( 2 ) This temporary effect disappears when the disk has been left for some hours in the vacuum . Next , with regard to vapour of oil , we cannot suppose its effect to be so large or so different in character and constancy from that of aqueous vapour as to account for the effect observed . Add to this that the effect takes place with an uncoated metallic disk probably to the same extent as with a coated one . The same remark may be made with regard to vapour of mercury . The effect would therefore appear to be independent of the chemical nature of the residual gas and vapour around the disk . In order to prove that this effect is also independent of the pressure of the residual gas , it is only necessary to refer to the whole body of experiments which have been described , to see that between 4 inches and 0'25 inch there is no perceptible variation in the effect observed . 24 . The following generalization may now be made:(1 ) If a perfectly true aluminium disk ( without vibrations ) be made to rotate in a vertical plane at the earth 's surface , after the manner herein described , there will be an increase of the temperature of the disk , which is not due to communication of heat from the bearings or machinery , nor to the earth 's magnetic force . ( 2 ) This heating effect is independent of the density and chemical constitution of the residual air and vapour which surround the disk . ( 3 ) It is probable that the quantity of heat developed in disks of similar extent of surface and similar circumstances of motion is the same . For , in the first place , the quantity of heat developed in three aluminium disks , *05 , '0375 , '025 of an inch in thickness respectively , would appear to be the same , the relative thermometric effect for these disks varying inversely as their thickness , and being in the following proportions , 30 , 43 , 60 , as determined by one complete set of experiments . Again , the quantity of heat developed in the thick aluminium disk , with its surfaces both uncoated , was probably the same as when one surface was coated and one left bare , or as when both surfaces were coated . 25 . The authors will'not attempt here a further generalization , but they would desire to make one remark . In absence of definite knowledge of the nature of that mnedium which transmits radiant light and heat , it might be supposed possible that when a radiant body is in rapid motion , the intensity of its radiation is somewhat increased . But if we bear in mind that in these experiments the effect was observed after bringing the disk to rest , and that the temporary effect during rotation sometimes observed can probably be otherwise accounted for , we are forced to conclude that , as far as we may judge from these experiments ( and they are of a very delicate nature ) , there is no perceptible effect of motion upon radiation . In conclusion the authors desire to say that they are much indebted to Mr. Beckley , who not only invented the apparatus , but assisted at all the experiments , and without whom they could not have been pertformed in a manner so satisfactory . They are also indebted to Mr. Atkinson for his kindness in lending them a large gasometer , and to Mr. Browning and Mr. Lad for exceedingly true aluminium and ebonite disks .

112639

3701662

On the Bones of Birds at Different Periods of Their Growth

299

306

Proceedings of the Royal Society of London

John Davy

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0069

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112639

10.1098/rspl.1866.0069

http://www.jstor.org/stable/112639

Biology 2

Chemistry 1

Biology

III . " On the Bones of Birds at different Periods of their Growth . " By JOHN DAVY , M.D. , & .R.S . , &c. Received October 23 , 1866 . In this paper I beg to submit to the Royal Society the results of some further observations on the bones of birds , and more especially on those bones which in the adult contain air . In offering them , I would wish them to be considered as a continuation of those communicated on a former occasion , and published in the Proceedings of the Society* . In engaging in the inquiry I have had two objects chiefly in view : one to endeavour to determine whether at an early stage the bones , which at maturity contain air , differ essentially from those of birds which are then , and are permanently filled with marrow ; another , to endeavour to ascertain in the instance of the former , the rate at which their early contents are absorbed , or an approximatian to the time that air takes the place of the medulla . The birds of the first kind subjected to observation have been the following : the common fowl , duck , goose , turkey , pheasant , partridge , grouse , rook , common crow , owl , sparrow-hawk , buzzard , blue tit ; of the second kind , the woodcock , blackbird , water-ouzel , marten , swift , greenfinch , titlark , sparrow , stonechat , blackcap , yellow ammer , little sandpipe , canary . I. Of the Common Fowl.-Of this bird I have examined the bones at different ages in a large number of instances . A few are selected as most characteristic : 1 . Of a foetal chick taken from the egg on the fourteenth day of incubation , the bones of the extremities were much advanced , the inferior more than the superior . Their epiphyses were almost gelatinous ; but the shafts were partially ossified , and had already some firmness . In both the humeri and femora , medullary matter was found . It was of a red colour , and under the microscope exhibited the usual character of this tissue . Broken up , in each were seen numerous oil-globules , with which were mixed blood-corpuscles and other corpuscles of a smaller size , some circular , some of an irregular form . Vol. xiv . 337 , 440 , 475 . 2 . A chicken twenty-eight days old , reckoning from the time of hatching , was found dead on the 12th of January ; during the preceding night there had been a severe frost . It weighed 10,275 grs. ; one of its humeri in its moist state weighed 2'5 grs. ; one of its femora 8 grs. In each of them a soft red medullary matter was detected , which , like the preceding , was composed of oil-globules , blood-corpuscles , and smaller colourless corpuscles or cells . The contents of the ulna and clavicular arch were similar , but in the latter the quantity of medullary matter was very minute . 3 . Of a pullet three months old , which had been hatched on the 6th of April , and weighed , when examined , two pounds , the humeri thoroughly ossified , sank in water . From one of them , opened under water , a few airbubbles only escaped , which came from its superior extremity . The canal of the bone , excepting the small portion from which the air proceeded , was full of red marrow of the usual appearance of medullary tissue , and with similar contents . A communication was found to exist by the air-foramen between the cancellated structure towards the head of the bone and the lung , through the adjoining air-sac . 4 . Of another pullet of the same brood , but of more advanced growth , which , though three days younger when examined , weighed two pounds and three-quarters , the humeri sank in water , but in sinking maintained a perpendicular position . One of them laid open was found to contain in its inferior portion , to the extent of '7 inch , marrow ; in its superior , to the extent of 18 inch , air . 5 . Of a pullet three months and eleven days old , which had been hatched on the 28th of May , the humeri floated in water . In one of them , laid open , a small portion of marrow was found in the cancellated structure of its distal extremity ; and in this portion a conspicuous blood-vessel terminated , 6 . Of a cock five months old , which weighed five pounds , the testes large , and abounding in sperm-cells and spermatozoa , the humeri contained only air . II . Of the Partridge.-Of one shot on the 1st of September , which weighed 4136 grs. , the humeri and femora sank in water ; in sinking the distal extremity of the former reached.the bottom first . From one of these , opened under water , a very little air escaped . The lining membrane was very vascular , and the lower one-fourth of the canal was full of blood of a dark colour , contained apparently in varicose vessels . Under the microscope , no oil-globules were distinguishable in the blood , only blood-corpuscles ; nor in any part of the cavity were there found any remains of marrow . 2 . Of another , shot on the same day , which weighed 5226 grs. , the humeri swam in water , the femora sank . Air only was found in the former . On the lining membrane there were two or three delicate vessels containing florid blood . The femora were full of a reddish marrow . 3 . Of another , shot on the 19th of October , which weighed 5-132 grs. , Dthe state of the humeri and femora was very similar to that of the preceding , The humeri contained only air , the femora only marrow ; the lining membrane of the former was finely vascular ; the medullary tissue of the latter abounded in oil-globules and corpuscles suggestive of bloodcorpuscles altered . III . Of the Pheasant.-Of a female shot on the 9th of October , both the humeri and femora swam in water . Both contained air without any marrow . The former were perfectly white , and no vessels were visible in their lining membrane ; the latter were of a reddish hue , and their lining membrane was beautifully vascular , the vessels delicately ramifying , of a bright florid hue , and anastomosing , and this throughout the whole of the circumference . 2 . Of another female , shot on the 17th of October , the humeri contained only air , the femora air with a trace of marrow* . The latter were redder than the former , and their lining membrane was very vascular . IV . Of the Goose.-Of one hatched in the spring , which , when examined on the 26th June , weighed eight pounds , the humeri sank in water . They were full of marrow of a light bright-red colour . The quantity collected from one of them was about 82 grs. It exhibited the usual character of medullary cellular structure , and was rich in oil , which in drying exuded copiously from it ; but it contained comparatively few blood-corpuscles or blood-vessels , of which these corpuscles were the index . 2 . Of another hatched on the 22nd of April , which on the 7th of August weighed nine pounds and a half , a humerus dissected out weighed 561 grs. , was 7'5 inches in length , and its shaft between *4 and *5 inch in width . It sank in water . Its upper third portion was of a darker hue than its inferior two-thirds . The latter was full of a light-red marrow , abounding in oil. . It owed its reddish hue to blood-vessels in the medullary structure . The former , entirely without air , contained a collection of blood-vessels resting on a cancellated structure . These vessels had the appearance of veins , seemed largely varicose , and were full of dark blood , which ( examined whilst warm ) was still fluid . Of the other wing , the humerus was somewhat different the difference was in the superior portion . Although the bone sank in water , a little air was found in this portion , and the blood-vessels in it were less distended , and contained , instead of dark blood , aerated blood of a florid hue . The marrow , which occupied about twothirds of the shaft , terminated abruptly superiorly , and there a pretty large blood-vessel united the two parts the medullary and the varicose portions . 3 . Of another hatched in the spring , examined on the 31st of October , the humeri contained only air . The lining membrane of its cavity was rich in blood-vessels . 4 . Of the humlerus of a goose hatched in the spring , weighing on the 2nd of November nine pounds , the canal was found full of air , with the exception of its inferior one-third ; this contained marrow rich in oil . In one of several portions of it submitted to the microscope , a red vessel was seen containing granules and oil-globules . In one direction it ended abruptly , as if torn ; in the other it was lost , as it were , by diffusion into , or blending with the cells of the medullary tissue . The upper portion of the marrow , it may be remarked , where it came in contact with the air , had , as in some other specimens , a rounded well-defined surface . In this instance no large blood-vessels were found in any part of the bone ; and on the delicate membrane connecting the trabecuiei of the cancellated structure , only a very few delicate vessels of a florid hue were to be seen . 5 . Of a fifth , also hatched in the spring , when examined on the 20th of November , the humeri , like those of the last but one , were found to contain only air . Their lining membrane was very vascular and partially varicose . V. Of the Commoon Duck.-Of a young drake hatched on the 26th of April , which when weighed on the 13th of August was four pounds , the humeri sank in water . They containad a light reddish marrow , and were entirely destitute of air . 2 . Of two ducks of the same brood as the drake , the humeri , examined on the 15th of August , sank in water . Two-thirds of each were filled with marrow ; one-third , the upper portion , with dark blood , seemingly in varicose vessels , which were connected with a light-coloured delicate membrane . 3 . Of a duck , little more then one year old , the humeri contained only air . VI . Of the Red Grouse.-Of one , which on the 12th of August was not fully fledged ( it was shot for examination ) , the humeri contained air , the femora marrow . 2 . Of another more advanced , shot on the 31st of August , weighing a pound and a quarter , the humeri contained air , the femora a little marrow , but more air , the former inferiorly . 3 . Of a third , shot on the 28th of August , which weighed 8770 grs. , the humeri were hollow , the femora partially so , a little reddish marrow 'only remaining , and this in their inferior extremity . 4 . Of one shot on the 27th of August , which weighed 11,856 grs. , and which , judging from its plumage , was probably a spring bird , both the femora and humeri swam in water and were free from any trace of marrow . The liining membrane of the cavities of the femora was beautifully vascular , the vessels of a florid hue from the well-a6rated blood which they contained . The lining membrane of the humeri was similarly vascular , but in a less strongly marked manner . VII . Of the Rook.-Of a youngone not quite capable of flight , shot on the 11lth of May , and which th enu weighled 6132 grs. , the humeri sank in water ; they contained no air , but a soft marrow , of a blood-red colour . The bones were very vascular , and were easily cut . 2 . Of another , shot on the 22nd of June , when capable of flight , though the quill-feathers of its wings were only partially hollow , its weight 5113 grs. , the humeri sank in water in a perpendicular position . Of one which was examined , its inferior two-thirds were found full of a reddish marrow , its superior one-third of air . The proportion of oil seemed greatest in the distal part of the marrow . The bones were less vascula than those of the preceding , and pf greater firmness . 3 . Of a third , shot on the 23rd of June , then weighing 4982 grs. , which , judging from the state of its feathers , its bursa Fabricii , ovary , and oviduct , had been hatched in the spring , the humneri were full of air without a vestige of marrow * . VIII . Common C'ow.-Of one shot on the 1st of June , then weighing 5402 grs. , its quill-feathers not fully formed , the humeri sank in water , and contained only marrow . 2 . Of another shot on the 21st of June , weighing 6533 grs. , capable of flight , the humeri contained air . The lining membrane was very vascular . IX . Of the Tawny Owl.-Of a young one , examined on the 21st of June , then weighing 4796 grs. , its quill-feathers not fully formed , the humeri contained a very red marrow , and were entirely destitute of air . 2 . Of one of uncertain but mature age , judging from its general appearance , and which weighed on the 8th of April 5776 grs. , the humeri were full of air . There was also air in the scapular arch , and partially in the furcula , its proximate portion . X. Of the Sparrow-hawk.-Of a young one , which on the 31st of July weighed 3686 grs. , its sternumn then only partially ossified , still flexible , the humeri were for the most part hollow ; the little marrow they contained was confined to their distal portion . The same remark was applicable to the scapular arch . The femora contained even less marrow than the humeri ; they were very nearly full of air . XI . Of the Buzzard.-Of a young one taken from its nest on the 10th of June , when supposed to be about a fortnight old , then weighing 5293 grs. , the qiill-feathers of wings only sprouting , the bones generally were very vascular ; the humeri and femora sank in water . Their ossification was much advanced , but the sternum was still cartilaginous . After drying , all the bones floated in water . The humeri and femora , now laid open , were found to contain a red matter lining but not filling the cavities , suggestive of its having been , in its moist state , a fluid or a semifluid . In this , its dried state , it was of a firm consistence . After soaking in water and trituration , it formed an emulsion , which , as seen under the microscope , was found to contain oil-globules and particles of different kinds . Digested and heated in alcohol , it was partially dissolved , the solution becoming turbid on cooling . Evaporated , and as seen under the microscope , the residue , proportionally small , seemed to consist chiefly of fatty and oily matter ( stearine and olein ? ) , with some needle crystals . XII . Of the Blue Tit.---Of a young one taken from the nest on the 31st of May ; then weighing 28-5 grs. , quite naked , except a few delicate fibre-like feathers on the head , some yolk still remaining in the abdominal cavity , the humeri were very small and pale , so small that no attempt was made to examine them , except by crushing . Comminuted with a few drops of solution of salt , and subjected to the microscope , there were seen mixed with the fragments of cartilage , blood-corpuscles and oil-like globules . 2 . Of a young one , nearly fully fledged , which on the 3rd of August weighed 142 grs. , the humeri sank in water , maintaining a perpendicular position . They were completely formed and well ossified . Excepting towards their inferior extremity they were white , there to a small extent they were red . The white portion , at least nine-tenths of the entire length , contained air ; the red , not exceeding one-tenth , marrow which , as seen under the microscope , had all the character of medullary tissue and abounded in oil . 3 . Of a third , shot in the same place as the preceding , and probably of the same brood , which on the 18th of August weighed 179'5 grs. , the humeri floated in water , and were entirely full of air . The feathers of the abdomen were not fully formed , and the bursa Fabricii was much smaller than that of the preceding . From these results , may not the following conclusions be drawln ? First , that at an early stage , and up to a certain period of growth , marrow exists in the bones specified , of all the birds first named ; and that about the time of hatching the medullary tissue abounds less in oil or fatty matter than at a later , the proportion varying in different instances ; least probably in birds of prey , such as the buzzard and owl ; most in birds , the food of which is mostly vegetable , such as the goose . Secondly , that the substitution of air for marrow in those bones which are eventually hollow , varies as to time in different species ; is earlier in the rook , the crow , the grouse , the tit , than in the common fowl , duck , and goose , especially the latter ; the exchange of one for the other having probably some relation to the time of taking wing and the use of the parts ; and , in accordance , the humeri , except in the instance of the sparrow-hawk , seemed to have the marrow absorbed somewhat-earlier than the femora . It may be conjectured that , like the residual yolk in the young bird , the marrow in the bones in question may serve in part as food , nourishing in the act of its removal . Relative to the structure of the hollow bones , I have but a few words to offer . , In the humeri there is a peculiarity which may be deserving of mention . Towards the head of the bone , near the pneumatic foramen , the cancellated structure , connected more or less by a delicate membrane , performs the part of a valve , as indicated by its permitting a free access of air in one direction , but preventing in the other , its exit . This is clearly shown by the use of the blowpipe , and in no instance have I found an exception . In the humerus of the common fowl , in three instances ( a section of the bone having been made ) the air ias been found to enter from the pneumatic foramen by a small bony canal contiguous to the side of the bone , in length about '6 inch , in diameter about '06 inch * . It is said that the trabeculae , or minute columnue in the cancellated structure of the hollow bones , are also hollow . In some of those of the humeri of the adult buzzard I have found a canal , but not in others ; these were solid . Nor have I found them otherwise than solid in the humerus of the common fowl , goose , and turkey . As to the bones of those birds of the second kind , in which the marrow is persistent through life , I may briefly remark that in them , as in the former , at an early period the marrow seems to be comparatively poor in oily matter ; and that the earlier , the nearer the embryo state , the less is its degree of consistence , the nearer it is to a liquid , and the larger is the proportion of blood-corpuscles and of albuminous matter , and the smaller the proportion of the adipose . When mature of growth , the bones of these birds appear to be richer in oily matter than those of the former permanently without air . Thus the tibia of the one kind in the dried state invariably sinks in water , whilst that of the first kind only partially sinks ; the marrow in drying in the latter , from containing less oil , contracting more , and allowing of the entrance of air . In the radius and ulna the difference is less strongly marked ; these bones in their dried state commonly sinking in water , even when belonging to birds of the first kind . As regards the quality of marrow in the bones of different birds , the trials I have made have been very limited . I am disposed to infer from them that , besides differing , as in many instances it does in colour , it may differ also in composition , in the proportion of adipose matter and its kind , and in the proportion of albuminous matter ; in some , as in the bones of the goose , oil most abounding ; in others , as in those of the rook and buzzard , albuminous matter and fat of the stearine kind . Even in the bones of birds of the second kind , such as their long bones , there is a difference in this respect ; of these , all that I have examined sink in water , with the exception of the femora , which only partially sink , the marrow in them being less rich in adipose matter , and consequently in drying contracting more , and , as before remarked , admitting more air . As to the marked difference of birds of the two kinds in relation to the condition of their bones , the rationale is not very obvious . Perhaps an approximation to the truth , or to the probable , may be made by comparing the bones of birds of the two kinds , which are possessed of similar powers , the swift , for instance , and the buzzard , rivals in swiftness of -fight and enduring power of wing . How different are their humeri ! of the former , very short , strong , and compact , provided with firm and large processes for the attachment of muscles ; in the latter , long , hollow , ald light , and comparatively brittle , yet sufficiently firm to bear without fracture the muscles which act on them . Here , have we not after a manner a kind of substitution of qualities ? great strength and extended surface in small space in the one , for lightness with greater length of leverage in the other . Further , the one kind of bone , that which contains marrow , being less brittle than that which contains air , and more yielding , may be less liable to fracture ; a quality which , in the bird , before the ossification is complete , may be of essential service ; so that , teleologically considered , it may perhaps serve to account for the bones which are eventtually hollow having primarily marrow in place of air .

112640

3701662

On Poisson's Solution of the Accurate Equations Applicable to the Transmission of Sound through a Cylindrical Tube; and on the General Solution of Partial Differential Equations. [Abstract]

306

310

Proceedings of the Royal Society of London

R. Moon

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112640

http://www.jstor.org/stable/112640

Formulae

Fluid Dynamics

Mathematics

I. On Poisson 's Solution of the Accurate Equations applicable to the Trans-mission of Sound through a Cylindrical Tube ; and on the General Solution of Partial Differential Equations . " By R. MOON , M.A. , late Fellow of Queen 's College , Cambridge . Commnunicated by Prof. J. J. S-YLVESTER . Received INovember 14 , 1866 . ( Abstract . ) The pair of equations v=(Pf{ ( v+a)t which constitute Poisson 's solution of tih accuralte equations applying to the transmlission of sound through a cylindrical tube derived by La Grange 's method , have long attracted the attention of mathematicians . For La Grange 's equations we may substitute the following , viz. cv a2 dp a dt JD dx dv+D dp=o dx p2 dt The first of these is obtained from the equation of the Encyc . Met . ( Art . " Sound " ) ; by putting v for die and D for die dt p dx The second results from a similar substitution in the analytical condition , d[d ? q d/ die Poisson 's solution has always been regarded as imperfect , and may easily be shown to be so . I was some time ago struck by finding that the above equations , while they yielded with facility the result of Poisson , notwithstanding their simplicity , baffled every effort to extract from them one more consonant to the general exigencies of the problem . I had at this time arrived at the conclusion that the law of pressure assumed in the received theory of Fluid Motion could not be generally true , and in a Paper* communicated to the Royal Society , had pointed out that , in a certain case of motion , the assumption of the truth of that law led to a contradiction ; while in another case of motion the expression for the pressure given by the received theory was palpably erroneous . It occurred to me , therefore , that the defective law of pressure of the received theory accounted for the defective solution which alone was obtainable from the equations of motion derived from it . If the law of pressure of the received theory was not always true , if it held only when certain conditions were satisfied , those conditions would obviously have the effect of dismissing from the complete solution of the problem obtained on a perfect theory at least one of the two arbitrary functions which it must necessarily involve . With a view to establishing this point , assume the solution of the equations of motion to be contained in the pair of equations , F(xytpv ) = { f( ytpv ) } , . ( B ) F(tytop)4'={/ ( Z3)}* Jyv ee If these equations satisfy the equations ( A ) , the latter will equally be satisfied by the pair of equations , F(xytpv ) =v , F(wy tpv ) ={f(xy tpv ) } . But it is shown in my Paper that these latter can only satisfy the equations ( A ) on the supposition that F is of the form F==F(v alog , p ) . Moreover , since we have in equations ( B ) the function F equal to an X On the Trtue Theory of Pressure as applied to Elastie Fluids in Motion . 2c2 arbitrary function of f , conversely we must have f equal to an arbitrary function of 1 . I-ence , in exactly the same way in which it is proved that F must have the above form , we may equally prove that f , F , f must severally have the same form . It clearly results , therefore , from the above assumed solution ( B ) , that the equations ( A ) are insoluble , except on the assumption that the velocity may be expressed in terms of the density alone ; i. e. that we may assume v =f( ) . But substituting this value of v in equations ( A ) , the latter become dp a dp ( p ) Sz2 + D , / dt D 4 , '_ f ( p p+ D dt)_o dx P dt-whence we get ) ' . 2=p dpf_ ap2 1dp . / ( ^ p ' ~di\ dr\ and eventually , D being the value of p when v=O , +h v_ loc. -D P ? =- . ? a t } which is the most general solution of which the equations of motion are susceptible ; and which , making allowance for the difference of the ordinates employed in the two cases , y referring to the particle when in motion , and x to its position of rest , is identical with that of Poisson . The failure of mathematicians to derive from the equations of motion of the received theory a solution containing two arbitrary functions has hitherto , I apprehend , been universally attributed to difficulties of integration . So far is this view from being well founded , however , that in a postscript to my Paper it is shown that , assuming the pressure to follow any law whatever , a solution of the equations of motion can be obtained containing two arbitrary functions ; a result , however , which requires that the expression for the pressure shall satisfy certain conditions , which conditions are violated when the pressure is assumed to vary with the density alone . Whatever be the law of pressure , it must always be capable of being expressed in terms of x and t. Moreover , the velocity and density are in like manner severally capable of being expressed in terms of x and t ; whence it follows that we may always express x in terms of p and v , and equally that we can express t in terms of p and v ; so that , whatever be the law of pressure , we may assume it to be a function of p and v. Hence , assuming dp_dp , +dp dv , _p+ dv dx dp dax dv dx dx dx ' where R and V are functions of p and v only , we I have for our equations of motion the following , viz. dv R dp V dv ? Ct +D+b D ' & +dv D dp dx T2 dt of which the following pair of equations constitute the solution , viz. f2(p , v)=~ { V2 V2 -4Rp2 } Ae , ( p , ? ) 2V ' ' wheref , ( p , v ) , =const . , and f , ( p , v)=const . are the respective integrals of the ordinary differential equations , dv-_ W +4R dpdv- ? p 2 --dp = O , 2p which involve the variables v and p only . But this result is depellent on the fact of the following conditions being satisfied , viz. , that we have 3dp dv where K , =VVV2+411p2 , K , =VV4Rp2 , which conditions cannot be satisfied if the law of pressure depends upon the density only ( in which case =0 and R contains p only ) , as may easily be shown . With regard to the theory of Partial Differential Equations , I conceive that the methods indicated in the Paper will serve to elicit every solution of a partial differential equation of the second order and first degree , save one , viz. , an integral solution consisting of a simple relation between the variables x , y , z , free from arbitrary functions , and which is not derivable from a solution containing arbitrary fimctions , by assigning particular values to the latter . If the equation O=Rd2 + dz +TV d ; ? dxdy die have a first integral consisting of the pair of equations F(xyzpq)=of{f(xy-pq ) } , F(s yq ) =44 ( ytzIq ) , or consisting of the pair of equations F(xyzpq ) =0 , P( yzp= ) = { f(x yp , q ) } , or of the single equation F(yzp q ) = < / f(xJyzpq ) } , or of the single equation F(xyzp ) =0 ) then in every one of these cases we must have 0==R . F'(q)-S.(q ) . F'().(p ) + T. '(p ) , O-R . F'(x ) . F'(q3 T. F'(29 ) . F'(q ) + R. F'(q).2 + T. '(p ) ? }F'(z ) +Y . F'(p).F'(q ) . It is also shown with more or less of generality , and it is capable of being shown generally , that if the given equation admit of a complete integral solution containing two arbitrary functions , it will necessarily have two first integrals , each of which will be of the form F(xypq ) = { f(xyz)q } . It might have been added , that if the general equation of the second order and second degree be written O= Pr2 . ? P , . *2 2 ' t2 +P sP P. et + . st +Pyr+P.S . 8+Pe +P ; and it is satisfied by the equation F(yZ-pq ) ( { f(xypq ) } then F and f must severally satisfy all three of the following equations , viz. F'(p ) ' ( ) =0 , F'(x ) qr':(O , z , , , Y'p ) = 0 , F'( ) + F ' , ( )~ -m '( ) =0 , where 0-P~ , . 14--_P . 13 ( Ps2 +Pg.)1--Ps . lP , 0P nm2P , ,p 4-IP~2n2-P-P nP , 0-(2Pr--P2s . l+P./ 12)M +(2Pe 12-Ps . tPr)n -(P2_ Ps I+Pr ) . T ' he functions f/ , m , must satisfy the sa-ne conditions , except in the second of the above cases .

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3701662

Abstract of the Results of the Comparisons of the Standards of Length of England, France, Belgium, Prussia, Russia, India, Australia, Made at the Ordnance Survey Office, Southampton. [Abstract]

311

314

Proceedings of the Royal Society of London

A. R. Clarke|Henry James

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112641

http://www.jstor.org/stable/112641

Biography

Measurement

Biography

II . " Abstract of the Results of the Comparisons of the Standards of Length of England , France , Belgium , Prussia , Russia , India , Australia , made at the Ordnance Survey Office , Southampton . " By Captain A. R. CLARKE , R.E. , F.R.S. , &c. , under the Direction of Colonel Sir HENRY JAMES , R.E. , F.R.S. , &c. , Director of the Ordnance Survey . Received November 15 , 1866 . ( Abstract . ) In the preface to this paper , Sir Henry James gives an account of the circumstances under which the work was undertaken , as follows . ( A Table of results is appended , p. 313 . ) The principal triangulation of the United Kingdom was finished in 1851 ; and the triangulations of France , Belgium , Prussia , and Russia were so far advanced in 1860 , that , if connected , we should have a continuous triangulation from the Island of Yalentia on the south-west extremity of Ireland , in north latitude 51§ 55 ' 20 " , and longitude 10§ 20 ' 40 " west of Greenwich , to Orsk on the River Ural in Russia . It was therefore possible to measure the length of an arc of parallel in latitude 52 ? of about 75 ? , and to determine , by the assistance of the electric telegraph , the exact difference of longitude between the extremities of this arc , and thus obtain a crucial test of the accuracy of the figure and dimensions of the earth , as derived from the measurement of arcs of meridian , or the data for modifying the results previously arrived at . The Russian Government , therefore , at the instance of M. Otto Struve , Imperial Astronomer of Russia , invited ( in 1860 ) the cooperation of the Governments of Prussia , Belgium , France , and England , to effect this most important object , and to their great honour they all consented , and granted the necessary funds for the execution of the work . The portion of the work which was assigned to me , was the connexion of the triangulation of England with that of France and Belgium , and I published the results of this operation in 1862 * . But this work has been done in duplicate ; for when application was made to the French Government to permit the necessary observations to be made in France , they not only consented to allow this , but at the same time volunteered to join in the labour and expense of the work itself . It would obviously have been wrong to mix up observations made with different kinds of instruments and on different principles , and therefore it was agreed that the work should , in fact , be made in duplicate , both the French and English geometricians using exactly the same stations . The results obtained by the French geometricians is published in the Supplement to vol. ix . of the ' Mimorial du Depot G6neral de la Guerre , ' 1865 , and the agreement with the results obtained by the English is truly surprising . But however accurately the trigonometrical observations might be performed , it is obvious that , without a knowledge of the exact relative lepngths of the standards used as the units of measure in the triangulation of the several countries , it would be impossible accurately to express the length of the arc of parallel in terms of any one of the standards . It was therefore necessary that a comparison of the standards of length should be made , and as we had a building and apparatus expressly erected for the purpose of comparing standards at this Office , the English Government , on my recommendation , invited the Governments of the several countries named to send their standards here , and we have had the following compared with the greatest accuracy:1 . 1Russian standard , double toise , P. 2 . Prussian standard toise . 3 . Belgium standard toise . 4 . Platinum metre of the Royal Society , compared with the standard metre of France by 1M . Arago . 5 . English standard yards , A , B , C , 29 , 47 , 51 , 55 , 58 . 6 . Ordnance Survey 10-foot standard bar . 7 . Indian 10-foot standard bars , new and old . 8 . Australian 10-foot standard bar . 9 . In addition to the above , the 10-foot standard bar of the Cape of Good Hope was compared heie in 1844 . We have invited the Governments of Austria , Spain , and the United States of America , also to send their standards . We have been promised that of Austria , and , but for the unfortunate war in which she has been lately engaged , we should have received it before this . I have entrusted the execution of the work of comparison and the drawing up of the results to Captain Alexander R. Clarke of the Royal Engineers , who designed the apparatus used . The numerous comparisons to be made entailed a great amount of labour upon him and his assistants , Quartermaster Steel and Corporal Compton , of the Royal Engineers . Before the connexion of the triangulation of the several countries into one great network of triangles , extending across the entire breadth of Europe , and before the discovery of the electric telegraph and its extension from Valentia to the Ural Mountains , it was not possible to execute so vast an undertaking as that which is now in progress . It is , in fact , a work which could not possibly have been executed at any earlier period in the history of the world . The exact determination of the figure and dimensions of the earth has been the great aim of astronomers for upwards of two thousand years , and it is fortunate that we live in a time when men are so enlightened as to combine their labours to effect an ob t-I Expressed in Expressed in Expressed in Terms of the Expressed in lines of the Millimetres. . Standard Yard . inches . Toise . * 1~~~ Measures-- . Millimetre= o. Inch= . Line-=. . ; tit . The Yard ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . 100000000 36-000000 405-34622 914-39180 Copy No. 55 of the Yard at its Standard Temperature of 62-00 F ... ... ... ... . 0-99999960 35-999986 ! 40534606 914-39143 Ordnance Standard Foot , , , , , , 62-00 ... ... ... . . 033333284 11-999982 135-11521 304'79681 . Indian Standard Foot , , , , 6200 ... ... ... ... ... 033333611 12-000100 135-11653 304'79980 Ordnance 10-foot Bar . , , , , , 62-00 ... ... ... ... . . 3-33333717 120-000138 1351-15563 3047'97616 Ordnance 10-foot Bar 01 , , , , 6200 ... ... ... ... . . 3-33335432 120-000755 1351-16259 3047-99184 9 Indian 10-foot Bar Is , , , , , , 6200 ... ... ... . 333340138 120-002450 1351-18166 3048-03488 Indian 10-foot Bar 1B , , , , , , 62-00 ... ... ... ... . . 3-33353284 120-007182 1351-23495 3048-15508 Indian 10-foot Bar I , , , , 62-00 ... ... ... ... ... 333331457 119-999324 1351-14647 3047*95550 Australian Standard 04 , , , , 6200 ... ... ... ... ... 333330427 119-998954 1351'14230 3047-94608 . ' Australian Standard 01 , , , , 62-00 ... ... ... ... . . 333333747 120-000149 1351-15576 3047-97644 Ordnance Toise , , , , , 6125 ... ... ... ... . 2-13166458 76-739925 864-06219 1949-17660 Ordnance Metre , , , , , 6125 ... ... ... ... . . 1-09374800 39-374928 443-34662 1000-11420 Royal Society 's Metre a traits , , , 3200 ... ... ... ... ... 109360478 39-369772 443-28857 999-98324 Prussian Toise No. 10 , , , , , , 6125 ... ... ... ... ... 2-13150911 76-734328 863-99917 1949-03444 Belgian Toise No. 1 , , , , , 61-25 ... ... ... ... ... 2-13150851 76-734306 863-99893 1949-03390 Russian Double Toise P , , , , 61-25 ... ... ... ... ... 4-26300798 153-468287 1727-99419 3898'05952 The Toise ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . . 2-13351116 76-734402 864-00000 1949-03632 The Toise ... . . , ,. . 2'13151116 76'734402 864'00000 1949'03632 The Metre ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... . . 09362311 39-370432 44329600 100000000 C3 ject desired by all , and at the first moment when it was possible to execute it . A full detailed account of the 'Comparisons of the Standards of Length , ' with numerous plates , has just been published , and may be obtained from the agents for the sale of the publications of the Ordnance Survey .

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On the Formation of 'Cells' in Animal Bodies. [Abstract]

314

318

Proceedings of the Royal Society of London

E. Montgomery

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112642

http://www.jstor.org/stable/112642

Biology 3

Chemistry 1

Biology

I. " On the Formation of 'Cells ' in Animal Bodies . " By E. MONTGOMERY , M.D. Communicated by J. SIMON , Esq. Received November 8 , 1866 . ( Abstract . ) I. Observations , So called organic " cells , " chiefly those of various cancerous tumours , were seen , on the addition of water , to expand to several times their original size , and at last to vanish altogether into the surrounding medium . The " nucleus " did not always participate in this change , but at times remained unaltered , whilst the outer constituents of the " cell " were undergoing this process of expansion . This curious phenomenon of extreme dilatatioi is intelligible only on the sulpposition that the spherical bodies in question are in reality globules of a uniformly viscid material , which by imbibition swells out till at last its viscosity is overcome by the incrasing liquefaction . In embryonic tissues and in various tliours , single " nuclei " were seen , each surrounded by a shred of granular matter . On the addition of water there would bulge from one of the margins of the granular mass a segment of a clear globule , which continued growing until it had become a full sphere , which ultimately detached itself , and was carried away by the currents . At other times no such separate globule would be emitted , but the entire granular shred would itself gradually assume the spherical shape , ultimately encompassing the " nucleus , " and constituting with the same the most perfect typical " ( cell . " Not only single " nuclei " were found , each surrounded by a shred , but also clusters of two , four , and more were seen similarly enclosed by a proportionately large granular mass . Under these circumstances it sometimes occurred that , on the addition of water , the whole granular mass of such a cluster became transformed into a large sphere , containing two , four or more " nuclei . " The resulting body was to all appearance identical with shapes well known under the name of " mother-cells . " In all these cases the granular shred must have partly consisted of a viscid material , which , on imbibition , naturally assumed the spherical shape . Primary globules were surrounded by a secondary globule , and thus the typical " cell " was completed under the observer 's eye . In some instances the globules resulting from the transformation of the granular mass were at first bright and transparent , the granules having completely disappeared . They , however , gradually reformed , showing at first molecular motion , then crowding more and more , till at last the whole mass seemed to undergo coagulation . Alternate liquefaction and coagulation of the same material was found to play an important part in the development of " cells . " Masses of certain viscid materials do not , on imbibition , expand uniformly throughout their entire bulk , but globules of a definite size are emitted , as many as the mass will yield . The crystalline lens of many young animals affords , when treated with water , a beautiful illustration of this fact . Its homogeneous material is transformed , under the influence of imbibition , into a vast number of globules of nearly equal size . Hyaline embryonic tissues display , under similar conditions , the same phenomenon . Certain inferences lead one to suspect that this size-limiting property is due to the crystallizing propensity of some ingredient of these viscid substances . Blood-corpuscles , human blood corpuscles at least , are evidently tiny lumps of a uniformly viscid material . When broken up into fragments , each fragment assumes the spherical shape . On slow imbibition , they often emit a clear sphere , or a segment of one . In various specimens of foetal blood , each blood-corpuscle was seen to emit as many as two and even three equally sized globules , the original corpuscle being at last no more distinguishable from its descendants . This is sufficient proof of the uniformly viscous nature of the blood-corpuscles . In many cancers the most recently formed part consists of mere fibres . These after a time become " nucleated . " The " niuclei " are at first very elongated , this being due to the lateral pressure of the still fibrous texture . But as the mass gradually softens , the ovals expand more and more into spheres , forming the primary globules , round which , as has already been shown , a secondary globule is often seen to shape itself . Chemical differentiation transforms first one portion of the fibrous mass into viscid inaterial . This at once strives , by imbibition , to assume the globular shape . The remaining portion may or may not ultimately undergo similar transformation . Inflamed serous membranes become often densely " nucleated . " In the deeper layers , the " nuclei " are very elongated . At the surface they are perfectly globular , and are detached as minute opaque balls . These balls are the granulationor the pus-corpuscles . On imbibition , one portion of their soft material swells out , encompassing the rest , which , when forming a single uniform globule , goes under the name of granulation-corpuscle ; when , on the other hand , broken up into several granules , constitutes the famous pus- " cell . " This is an example of a second mode of " cell " -formation . Here the secondary globule is shaped from a portion of the primary mass . In some instances these " nuclei " or balls will , when still enclosed within the surrounding texture , undergo the above-mentioned change on imbibition , and thus whole rows of granulation or pus-corpuscles are seen to form . This second mode of " cell " -formation is still more strikingly manifested in epithelial textures . In the mucous membrane of the nose , for instance , the faint oval " nuclei " of the large scales become during disintegration more and more distinct and globular . The surrounding material of the scale gradually liquefies , and the minute balls , thus liberated , expand by imbibition into mucusor pus-corpuscles . It often succeeds to make them form in all perfection whilst they are still contained within the scale . In abscesses of the skin the pus-corpuscles are formed in exactly the same manner . They can often be watched , fully shaped , still enclosed within the scale . Here , it would seem , are " cells , " not the result of life , but rather of death . The multiple " nuclei " of pus-corpuscles are not the result of overfecundity , but are simply due to the disintegration of the non-imbibing portion of those oval or spherical clear-cut bodies , which are themselves so well known under the name of " nuclei . " The disintegration of this non-imbibing portion can be traced through all possible stages , down to the cluster of most irregularly shaped granules ( which , notwithstanding , have been looked upon as the result of fissiparous division ) , and has been made to represent the crowning feature of the cell theory . The same minute balls found swimming in the serum of a blister were seen , when treated with water , to disclose single bright clear cut " nuclei ; " when treated with acetic acid , to reveal the most typical multiple nuclei of pus-cells . II.--Experimental Verification . In all the above-cited observations the existence of a viscid , imbibing material was proved with almost conclusive evidence , -a viscid material which is capable of forming globules of a definite size , and which in the living organism actually forms such globules ; shapes , the nature of which has been hitherto mistaken . After a long search , the substance known under the name of myeline was found to be the desired material . When to myeline in its dry amorphous state water is added , slender tubes are seen to shoot forth from all free margins . These are sometimes wonderfully like nerve-tubes in appearance . They are most flexible and plastic . From this curious tendency of shooting forth in a rectilinear direction it was inferred that a crystallizing force must be at work . To counteract this tendency , and to oblige the substance to crystallize into globules , it was intimately mixed with white of egg . The result was most perfect . Instead of tubes , splendid clear globules , layer after layer , were formed , resembling closely those of the crystalline lens formed under similar conditions . Here was actually found a viscid substance which , on imbibition , formed globules of a definite size . The remaining task was comparatively an easy one . By mixing the myeline with blood-serum , globules were obtained showing the most lively molecular motion . When the serum somewhat : preponderated , the whole globules seemed , after a while , to undergo coagulation , and appeared often as beautifully and finely granulated as any real " cell . " When this mixture of myeline and serum was spread very thinly over the glass slide , there often started into existence , on the addition of water , small primary globules , round which an irregular mass of granular material became gradually detached from the glass slide . It at last shaped itself into a secondary globule , enclosing the primary one , and constituting with it , down to the minutest details , the most perfect typical " cell . " In many instances the nucleolus did not fail , and the narrow white margin , so often mistaken for a cell-wall , was always present . Beautiful " mothercells " were formed in the same manner . The next endeavour was to form " cells " according to the second mode . If the amorphous myeline be very thinly spread on the glass slide , instead of tubes there will form bodies looking like rings . They are actually double globules , the inner globule being more transparent than the outer . They correspond to the inner and outer substance of the abovementioned tubes . When these are left to dry , and then again acted upon with water , one portion will swell out into a clear globule , enclosing the rest as " nucleus . " These " nuclei " are either large and single , like those of granulation corpuscles , or they are multiple , exactly like those of puscells . Whole layers of perfect pus-corpuscles are thus formed . But , of course , more complicated shapes o'cur as well . Among these , for instance , many such pus-cell-like bodies enclosed within one large sphere . If , instead of water , serum be added to the thinly-spread myeline , biconcave disks will form , only generally much larger than blood-corpuscles . " Cells " being thus merely the physical result of chemical changes , they can no longer afford a last retreat to those specific forces called vital . Physiology must aim at being something more than the study of the functions of a variety of ultimate organic units . And pathology will gain new hope in considering that it is not really condemned to be the interpreter of the many abnormities to which the mysterious life of myriads of microscopical individuals seelme to be liable .

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3701662

Preliminary Notice of Results of Pendulum Experiments Made in India

318

319

Proceedings of the Royal Society of London

Lieut.-Col.Walker

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0073

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112643

10.1098/rspl.1866.0073

http://www.jstor.org/stable/112643

Meteorology

Biography

Meteorology

II . " IPreliminary Notice of Results of Pendulum Experiments made in India . " By Lieut.-Col.\WALKEni , F.R.S. : in a Letter to the President . Received September 21 , 1866 . I have the pleasure to enclose a provisional abstract of the results of Capt. Basevi 's observations with his pendulums during the past field season . Though provisional , it will probably be found to agree very closely with the final results , which will be deduced as soon as the corrections for buoyancy , temperature , &c. are finally known . Already these experiments are beginning to throw light on the subject of I-imalayan attraction ; for the observations clearly show that the force of gravity is less than it shouldc be theoretically at the stations in the vicinity of the Himnalayas , and that the difference between theory and practice diminishes the further the station is removed from the Himalayas . This is a remarkable confirmation of Airy 's opinion , that the strata of the earth below mountains are less dense than the strata below plains and the bed of the sea . Combining these observations with those that were used by Mr. Bailey ( including , I believe , all your own ) , the value of the ellipticity will be diminished from -g to 2-j ( approx. ) , and will therefore tend more closely to assimilate with Capt. Clarke 's value , x4 . * The pelndulum result is 28-4-E . S. [ Dee . 204 318 Field Season 1865-66 . Reduced to Mean Temperature 69 ? '69 . Observed vibraReduction to alue of ellipHeightt tions per diem i sia Compted Vibrations ticity , each above vacyto , reduced to using in ters of Usia.h Name of Station . Latitude . Mean mean sea-level . Means . ellticity . copar with SeaLevel. . Leel. . | Clarke , Bailey , ' No. 4 . iNo . 18 . 1 Clarke . Bailey . Usira . ew . 294285-3 . , , feet . + ' ? Dehra * ... ... ... ... 30 20( 0 2289 86076-426 85975-631 86026-029 11-192 10-970 86031-288 86031-0W6 -1 16 Nojli ... ... j 129 53 28 881 86076.843 85975-724 86026-284 9-681 9-490 86029777 86029-58 Kajliana ... ... 86049-777 860291586 1L Kaliana 9 ... | 29 30 55 826 86075992 85975-4(i6 86025-729 8-408 8-241 86028504 86028337 |1_9 Dateri ... ... | ' 28 44 5 719 86075-156 85974-782 04 86024609 595 . 1 860289 0777 8602 -7 l1 Usira ... .j H| 26 57 7 812 86070-520 85969-672 86020-096 ... ... ... ... ... ... ... ... ... ... ... ... ... ... Kew ... ... ... ... ... 51 28 10( ? ) ... ... 86165483 86064-410 86114-947 91-682 89-871 86111'778 86109-967 f , ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ * Dehra is situated in a valley between the Hinalayas and the Siwaliks . *-E9 00 0x O ' : < o5 ^ ? T%1

112644

3701662

On the Appendicular Skeleton of the Primates. [Abstract]

320

321

Proceedings of the Royal Society of London

St. George Mivart

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112644

http://www.jstor.org/stable/112644

Anatomy 2

Biography

Anatomy

" On the Appendicular Skeleton of the Primates . " By ST . GEOaGE MIVART , F.Z.S. , Lecturer on Comparative Anatomy at St. Mary 's Hospital . Communicated by Prof. HUXLEY..Received November 22 , 1866 . ( Abstract . ) The author began by mentioning the principal variations found in the order Primates , as to the absolute and relative length of the pectoral limb with and without the manus ; and then taking each bone separately , described the modifications undergone by each in all the genera of the order* ; as also the relative size of the segments and bones of the limb compared to each other and to the spine . The pelvic limb was then similarly treated of , and , in addition , its segments and bones were compared with the homotypal segments and bones of the pectoral limb . The author after this reconsidered the question as to the use of the terms " hand " and " foot , " and the applicability of the term " Quadrumanous " to Apes and Lemuroids . He controverted the position lately assumed by Dr. Lucaet , that both anatomically and physiologically the pes of apes is more like the human hand than the human foot . At the same time he recommended the use of unambiguous homological terms , such as " manus " and " pes " ( already adopted by some ) instead of " hand " and " foot , " in all treatises on comparative anatomy . Tables of the dimensions and proportions of the limbs , their segments , and bones were then given , exhibiting the variations presented in these respects throughout the whole series of genera . The author then considered the more peculiar forms of the order , beginning with Man . The principal resemblances and differences in form , size , and proportion between the human appendicular skeleton and that of other primates were given in detail , followed by a list of those points in which man differs , as to the bony structure of his limbs , from all other primates . The limb-skeletons of the Orang , Marmoset , Indri , Slender Lemur , Tarsier , and Aye-aye were then similarly reviewed , and lists given of the absolute peculiarities found in each . The conclusion arrived at from these comparisons was , that Man differs less from the higher Apes than do certain primates below him from each Except certain Lemuroids , of which no specimens exist in this country . t Abhandlungen von der Senckenbergischen Naturforschenden Gesellschaft . Frankfort , 1865 , vol. . p. 275 . other ; and that he , thus judged , evidently takes his place amongst the members of the suborder Anthropoidea . A list of the principal osteological variations presented by the several groups and genera of the order , before unmentioned , was then given ; and the author concluded by stating what he believed to be the degrees of affinity existing between the various forms , as far as could be ascertained from the consideration of the appendicular skeleton exclusively .

112645

3701662

Actinometrical Observations among the Alps, with the Description of a New Actinometer

321

330

Proceedings of the Royal Society of London

George C. Hodgkinson

fla

6.0.4

http://dx.doi.org/10.1098/rspl.1866.0075

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112645

10.1098/rspl.1866.0075

http://www.jstor.org/stable/112645

Thermodynamics

Astronomy

Thermodynamics

I. " Actinometrical Observations among the Alps , with the Descrip. . tion of a new Actinometer . ' ' By the Rev. GEORGE C. HODGKINSON . In a Letter to Professor STOKES , Sec. R.S. Communicated by Professor STOKES . Received December 2 , 1866 . SIR , --I have the honour to forward you an account of some actinometrical observations made last summer on the summit of Mont Blanc and at Chamonix , and at the same time to thank the Committee of the Royal Society for the grant which they were so good as to vote me for that object . I reached Chamonix on the 7th of July , in bad weather , which had been prevailing for some time , but which ushered in a fine week very opportunely for my work . After allowing a few days for the weather to settle and for the snow to consolidate , I left Chamonix in the afternoon of Friday the 13th for the Grands Mulets , having previously arranged for a corresponding series of observations being taken the next morning in the valley . Leaving the Grands Mulets at about 2 ? A.M. on the 14th , I reached the summit of Mont Blanc about 8 A.M. , and proceeded at once to work . I had brought with me from England two of Newman 's mountain-barometers , a thermobarometer of Casella , six small thermometers graduated on the stem ( three for the dry- , and three for the wet-bulb observations ) , three of the tubes described in Appendix ( A ) , with two of the actinometers in each . I carried besides an aneroid by Cooke , which proved to be of excellent quality . The third set of apparatus was taken in some faint hope that I might be able to arrange for a third set of simultaneous readings at the Grands Mulets . In this I was disappointed. . Notwithstanding the greatest care had been taken , one of the barometers was found on the Brevent on the 9th to be deranged , and one of the actinometers to be broken ; and on the 12th a second actinometer was broken at Chamonix by an accident . I thought it best to leave the remaining barometer for the valley observations , and to depend upon the thermobarometer , as being more portable and less liable to fracture , for the readings on the summit . I was eventually obliged to rest satisfied with a single observation of this ; and the downward range of the small thermometer unfortunately proved too 2 n limited for the wet-bulb readings . Thus the meteorological observations at the upper station are of the scantiest . Neither above nor below were the actinometrical readings so continuous as I had wished to make them . I had no one with me on the summit capable of rendering me the smallest assistance ; but it is some consolation to think that , even had this been otherwise , the results could not , under the circumstances , have been materially enhanced . There either did not exist , or I failed to detect , as the sun 's altitude increased , anything like a unifornm progression of actinic power at either station during the limited time in which the observations were continued . The results do little more than determine the ratio of the average intensity at the two stations for a portion of the forenoon . This indeed was the main object which I had in view . For looking at the experience of Principal Forbes under easier conditions , when the continuance of the observations , as long as the clearness of the sky might last , presented no difficulty , I did not at all anticipate being able to trace a dependence of the actinic power on the hygrometric state of the atmosphere . lie thus remarks ( Bakerian Lecture , Phil. Trans. part 2 for 1842 , p. 253 ) of the experiments on the Faulhorn and at Brienz , that " it cannot be affirmed they are sufficient to show the kind of dependence which the opacity has on the dampness , and that the values of the coefficient of extinction do not present any correspondence with the hygrometric variations ; " and again , p. 268 , " It must be confessed that no evident relation to the hygrometric condition of the air appears in the individual observations . " From the experiments of the 14th of July the actinic ratio between the summit of Mont Blanc and Chamonix , from 91 311 " to 101 " 11m apparent time , presents , with a single exception , a gradual decrease from 1 244 to 1*206 . The interest of a comparison of these results with those which Principal Forbes obtained between the Faulhorn and Brienz is unfortunately diminished by the fact that his actinometer was not furnished with an internal thermometer for ascertaining the temperature of the liquid employed . This was ammonio-sulphate of copper , which has a coefficient of dilatation varying from 1 at 60 ? F. , to 2-562 at 32 ? F. , and 0-626 at 100 ? F. His recorded numbers for three hours before and three hours after apparent noon derived from his freehand curve , are as follows : Hour . Ratio . 9 ... ... ... ... ... ... ... . 1'141 10 ... ... ... ... ... ... . 1-214 11..1 ... ... ... ... . . 1'345 12 ... ... ... ... ... ... ... . 1-219 1 ... ... ... ... ... ... . 1-078 2 ... ... ... ... 1-207 3 ... ... ... ... ... ... . . 1-217 At 10 " on the Faulhorn the ratio seems to have been rapidly increasing ; on Mont Blanc it was slowly diminishing . The actual amount of the ratio at 1 Oh is almost exactly coincident in the two cases ; but at 1 1h on the Faulhorn it was 1'345 , a value much higher than any which was obtained at any time on Mont Blanc , or seemed likely to have been obtained at that hour had the observations been continued so long . What share the greater depression of the lower station in the experiments of 1832 , the more complete isolation of the upper station in those of 1866 , or variable atmospheric conditions in both sets may severally have had in contributing to this effect , remains a matter for future investigation . The respective heights of the stations are as follows : English ft. English ft. Faulorn ... ... . 8799 Difference 6853 Brienz ... ... ... 1946 Mont Blanc ... . 15784 Difference 12359 Chamonix ... ... 3425 Professor Forbes gives the numbersFaulhorn. . 8747 Difference 6844 . Brienz ... ... ... . 1903 The sky during the observations was not only cloudless , but , as seen from the summit , remarkably clear . The observations have all been reduced by means of Tables derived from Gmelin 's ' Chemistry , ' vol. i. p. 231 , to what they would have been had the mean temperature of the liquid during each minute been 32 ? F. By a prolonged and careful comparison of actinometers ( K ) and ( A ) , the factor for reducing the indications of ( K ) to the standard of ( A ) was found to be 1-29 . Considerable practice is necessary to acquire expertness in the use of the actinometer employed . It is desirable , as nearly as may be , to work it at such a temperature that the rise in the sun may be equal to the fall in the shade . If the mean of the two mean temperatures of the liquid , in taking the shade observations which precede and follow a given sun , differ much from the mean temperature of the liquid during that sun , a sensible error will be introduced . This , however , is to a great extent eliminated by taking the mean of three , and still more completely by taking the mean of five successive actinic results in column ( I ) . The difficulty of using the instrument was overcome by the kind cooperation of several friends for the Chamonix observations . To the good offices of my cousin , Mr. G. F. Hodgkinson , were added those of a lady , a worthy sister of one of the foremost mathematicians of his year , and her two nieces . Under her auspices an admirable arrangement of the work was made , by which each of the party was responsible for a precise and definite function , the adjustment and direction of the instrument , with the shading and unshading , the watch , the readings , and the records . To this friendly and efficient help I am greatly indebted for whatever success has been achieved . How small this is , no one can be more sensible than myself ; yet I venture to hope that when the difficulty of the undertaking is considered , to those at least who are acquainted with the experience of Principal Forbes in 1832 , 1841 , and 1842 , as given in his Bakerian Lecture , the results will not appear either disappointing or discouraging . The season was extremely unfavourable for the further prosecution of the work . Looking to the imperfection of the instrument employed by Principal Forbes in his observations in 1832 , it would seem to be highly desirable that his experiments on the column of air between the Faulhorn and Brienz should be repeated , and that other pairs of stations , intermediate in character to that and the Chamonix pair , should be essayed . I have selected , in the hope of future opportunities , the following among others : English ft. English ft. Becca di Nona ... . . , 10384 Difference 8415 Aosta ... ... ... ... 1969 and should the Piz Stella prove readily accessible , Piz Stella ... ... ... . 1171 9Piz Stella* e* A. Apparenttiine of com. mencing eachobs . hm8 28s 8 30 8 31 . 8 33 8 342 9 62 989 90 9 11 9 121 9 14 9 152 9 19l 9 21 9 223 9 24 9 25 9 27 9 291 9 31 9 321 9 33 9 352 9 36 9 381 9 39 9 412 9 43 9 442 9 514 9 53 9 542 9 56 9 574 9 59 o1 0o1 10 2 10 5 10 65 10 86 10 92 10 11 10122 10 192 10 21 10 222 10 24 10 252 Observations among the Alps . 325 Summit of Mont Blanc , July 14 , 1866 , Actinometer ( K ) . Sunm. . Teet Change Change Solar Solar ActinoB , C D. , E. |G ha n. gK I. 0 , Initial m inaerChun hade effect Tempo effect remeter Ave , main sun , insliade , rature of ( K ) reAve shads reading . reading . r. liuid . duced xduced . 320 Fr. to ( A ) . x0x0xx0x0x0xx0x0x0x0x0x0x0x0x0x0x0x0x0x0x0x 1732 1172 1238 600 662 2098 1890 2200 1840 2200 1882 2120 1460 1.300 1852 1582 2026 1754 1760 1472 1906 1568 1972 1692 2146 1880 2290 2068 2454 1908 1558 1894 1608 2022 1680 2062 1788 2126 1820 2190 1904 2426 2060 2380 1270 1086 1600 1386 1764 1192 1300 602 714 50 1792 2272 1834 2234 1810 2270 1780 1198 1800 1538 2032 1690 2178 1400 1898 1540 1974 1620 2150 1840 2358 1974 2514 2100 1580 1980 1546.2042 1662 2094 1684 2164 1740 2220 1810 2290 2026 2440 1950 992 1580 1282 1828 1410 128 114 382 394 388 500 450 424 426 406 458 478 446 422 434 414 376 400 386 380 494 442 540 636 612 306 366 390 340 262 314 326 360 366 352 306 316 354 328 348 360 378 386 380 400 430 278 318 354 716 738 718 772 753 788 775 772 789 765 787 789 781 760 788 783 758 783 776 795 792 778 51 50 50 50 50 48 48 49 49 49 49 49 50 50 50 50 51 51 51 52 52 52 708 730 711 . 764 745 781 768 764 781 757 779 781 773 752 780 775 750 774 768 786 913 942 917 986 961 1007 991 985 1007 977 1003 1007 996 970 1006 1000 967 999 991 1014 955 995 994 993 996 998 1002 992 988 993 994 1001 783 1010 769 992 The recorded numbers denote tenths of the scale which is divided to millimetres , the last figure being assigned by estimation . _ __ _ . I. t_ Chamonix , July 14 , 1866 , Actinometer ( A ) . A. B , C. D. E. F. G. H. I. L. Appa'renttime Sun Solar of comSO . Initial TerChange Change effect Tempeeffect Ave. mencing shade rading . minal in sun , inshade , unreratureof reduced rages . each obx . reading . + . duced . liquid . to 32 ? F. servation , hm8 224 X 1230 780 450 8 24 116( ) 1560 400 837 85 811 8 254 X 1514 1030 424 8 27 0 140 1554 414 818 85 793 812 8 28X 1484 1100 3S4 8 30 0 1180 164 ) 460 857 85 831 799 8 311 X 1504 1094 410 '833 O 1204 1614 410 830 85 804 794 8 34 X 1330 900 430 8 36 O 950 1304 354 779 84 755 805 8 37 X 1214 794 420 8 39 0 890 1280 390 814 84 789 803 8 40 X 1230 802 428 8 42 0 842 1310 468 872 84 846 800 8 431 X 8112 802 380 8 45 0 812 1280 468 848 84 822 803 8 461 X 1202 822 380 8 48 0 940 1.380 440 814 84 789 802 8 494 X 1280 912 368 8 51 0 1040 1460 420 795 85 770 791 8 52 X 1312 930 382 8 54 0 1032 1462 430 806 85 781 797 8 55 ' X 1350 980 370 8 57 0 1092 1542 450 820 85 795 795 8 584 X 1452 1080 370:9 00 1182 1660 478 878 85 851a 807 9 11 X 1744 1330 414 930 1394 1780 386 801 86 776 9 44 X 1620 1204 416 9 64 X 1204 800 404 980 890 1324 434 841 84 816 9 91 X 1230 820 410 9 11 0 950 1394 444 844 85 818 821 ? 9 12 X 1264 874 390 9 14 0 1014 148,0 466 856 85 830 807 915 X 1420 1030 390 9 17 0 1124 1554 430 808 85 783 800 9 183 X 1420 1054 366 19 20 0 1220 1670 450 813 85 788 19 21 X 1560O 1180360 9 23 0 1310 17 ; 0 480 9 274 X 1554 1294 260 9 29 0 1414 1914 500 820 86 794 9 304 X 1774 1394 380 9 32 0 1560 2000 440 820 86 794 798 933 X 1870 1490 380 9 35 0 1614 2100 486 831 86 805 811 9 361 X 2024 1710 310 9 38 0 1664 2210 546 876 86 849 809 TABLE ( contnued ) . A. B. C. D. E. F. G , H. I. L. Apparent time Sun Solar Solar of corno n TerChngan C ge fact lere AveO~~~~ , IX~nitiapl effect effect Avemencing hae ad inal in m sun , in shade unr rature reduced raes each obreading . + . duced . of liquid . to 32 F. servation . hm9 394 9 41 9 42 . 9 44 9 454 9 47 9 481 9 50 9 514 10 42 10 6 10 74 10 9 10 1010 12 10 134 10 15 10 164 10 18 to10 19 10 274 10 29 10 302 10 32 10 331 10 35 10 364 X0X0X0X0XX0X0X0X0X0XX0XOXOX 2070 1590 1990 1590 1940 1500 2040 1854 2036 1190 1094 1494 1334 1690 1374 1750 1490 1960 1810 2270 1540 1424 1820 1688 2130 1740 2182 1720 2084 1654 2082 1634 2064 1704 2454 1780 830 1584 1120 1820 1344 1880 1384 2050 1670 1404 1950 1234 1934 1504 2224 1820 2300 1882 494 492 564 600 490 486 506 560 594 510 536 560 350 336 306 336 256 360 374 346 366 290 320 306 316 310 300 837 813 885 896 857 846 862 888 899 821 849 865 0 86 86 87 89 89 90 90 91 93 94 95 811 787 857 869 828 818 833 858 869 792 818 833 822 835 838 826 841 853 814 numbers denote tenths of the scale which is divided to millimetres , the last figure being assigned by estimation . The numbers in column L are the means of the five nearest numbers in the preceding column when not less than two observations precede and follow the one against which the average number is placed , otherwise the mean of the three nearest numbers . The recorded Comparison of Results , Summit of Mont Blanc and Chamonix . M. Blanc . ActinorneChan onix . ter ( K ) reactino meduced to ter ( A ) . actinoraeter ( A ) . 812 799 794 805 803 800 803 802 791 797 795 807 955 ' 821 807 800 995 994 993 798 Ratio of actinometers , Mont Blanc and Chamonix . 1-163 1-244 Apparent time . hm9 34 9 35 9 37 9 38 9 40 9 41 9 44 9 47 9 56 9 59 10 2 10 5 10 8 10 9 10 11 10 12 10 15 10 21 10 24 10 32 ActinomeRatio of ter ( K ) reChamonix actinomeduced to actinomei ters , Mont actinometer ( A ) . Blanc and ter ( A ) . Chamonix . 996 998 ... . . 1002 992 988 993 994 1001 1014 1010 9992 o ... ... 811 809 822 835 838 826 841 853 814 1-228 1-234 1-219 1-212 1-206 Meteorological Observations on summit of Mont Blanc and at Chamonix , July 14 , 1866 . Mont Blanc . Chamonix . IMean Apparent Barometer time . time . TlcrmoThermoThermo . corrected ThermoThermoe meter meter and remeter meter arom ( dry ) . ( wet ) . deed to ( dry ) . ( wet ) . 32 ? F. hmhm8 30 8 25 2690 69 F. F. 8 40 8 35 1.6-86 22 F. Below 20j 9 30 9 25 Boiling ... . . 72 F. . 59 F. 9 45 940 point = 225 F. Below 0 1045 11 0 40 1 F. F. 11 0 10 55 24- . 25 20 . 8 ... . 2 F. 63 F. APPENDIX ( A ) . Description of the Actinometer . The actinoreter employed consists of a thermometer with a spherical bulb one inch in diameter , and a tube , of which an inch and a half next the bulb is , for a reason which will presently be apparent , left unscaled . The succeeding ten inches is made to represent , as nearly as may be , the range 328 Apparent time . hm8 27 8 30 8 33 8 36 8 39 8 42 8 45 8 48 8 51 8 54 8 57 909 11 9 14 9 17 9 24 9 27 9 31 9 32 . _~---~ -g~~~~~~ I ! _ __ IIIII from 40 ? F. to 45 ? F. At eleven inches and a half from the bulb the tube is widened , so that the following inch and a half may represent the range from 45 ? F. to 115 ? F. The tube then finishes in a spheroidal chamber , of which the diameters are about an inch and half an inch . The widened portion of the tube may be dispensed with , as the correction which it serves to ascertain may be otherwise found by means of a Table experimentally constructed for each instrument . In that case the spheroidal chamber , in which the tube will then terminate at eleven and a half inches from the bulb , should be made somewhat larger . The fluid employed is alcohol coloured with a drop of pure aniline-blue . A considerable quantity of air is left in the chamber . As a running column has to be read at a particular instant , great plainness is the first requisite for the scale . On this account graduation on the tube has not been adopted ; but at an inch and a half from the bulb is attached an ivory scale , nine-tenths of an inch broad and eleven and a half inches long ( or somewhat less if the widened tube be dispensed with ) , its other extremity coinciding with the commencement of the spheroidal chamber . This scale is graduated throughout in millimetres . The number of millimetres corresponding to each degree Fahr. on the tube of narrow bore , and to every fifth degree from 45 ? to 115 ? on the widened tube , should be noted on the back of the scale . The principle of the instrument is the same as that of Sir J. Herschel 's ; and it is to be worked according to the directions given by him in The Manual of Scientific Enquiry . ' It was devised for mountain use , where the weight of the Herschel and the fragility of its internal thermometer are elements of difficulty . It has also the advantage of being less costly . The air-chamber is made to serve the purpose of the screw in the HIerschel , viz. that of altering at will , according to circumstances , the range of the thermometer . This is effected by throwing off into the chamber a greater or less quantity of fluid , retaining it there by holding the instrument with the chamber end somewhat lower than the bulb , and working with the remaining column . As alcohol expands unequally between its freezingand boilingpoints , a small correction is necessary , depending on the temperature of the alcohol at the time of working , This temperature is ascertained by noting the point in the widened tube , at which the column stands , when the fluid is thrown off into the chamber . The excess of this temperature above 45 ? F. , the point from which the fluid is thrown off , has to be added to the temperature between 40 ? and 45 ? shownby the head of the working column , in order to have the true temperature . From the openness of the scale , and consequent small range of the instrumentfor any one adjustment , it is necessary to select for working a temperature not much removed from that at which the rise in the sun is equal to the fall in the shade . This temperature , which may be called the temperature of equilibrium , will vary practically , according to the solar intensity , from some 5 ? F. to 20 ? F. above the temperature of the surrounding influences . By driving the fluid into the chamber until the temperature of equilibrium is represented at a point near the middle of the tube , the readings will go on for a considerable time without altering the quantity of fluid in the chamber , and ten inches of graduation are found to be ample under all circumstances . By thus taking all the readings , so to speak , on the balance , a uniformity of proceeding is secured , which is not without its value . The instrument , constructed according to the dimensions here given , will denote the intensity of the noonday sun at the summer solstice near the sea-level in England by about 100 divisions of the scale . Owing to the difficulty of shading satisfactorily , and anomalies found to occur in observing among the snow-fields on the high crests of the Alps , the following contrivance has been adopted : A plain telescope-tube of bright metal , 18 inches long and 27 inches in diameter , open at both ends , ,is pierced in its central section with a circular hole 1to 1inch in diameter , from which springs a flanged shoulder projecting about inch to receive a perforated split bung , which clasps the thermometer-stem and holds the bulb firmly in the centre of the axis of the tube . Two caps , fitted at the ends with clean plate-glass , are made to slide off and on at the two ends to admit of the glasses being readily wiped . By protecting these with a little wadding , the tube serves as a case for two actinometers . In the central section of the tube , made by a plane perpendicular to its axis , and nearly 90 ? from the centre of the circular hole , is a screw to attach the tube to an altitude and azimuth motion , by means of which it may be kept constantly directed towards the sun . Below the joint is provided means of attachment to an alpenstock or iceaxe . The shading is effected by means of a loose-fitting cap , bottomed by a chamber with air-holes . The shadow of the large thermometer-bulb on the lower glass , or on a plane held beneath it , is a guide to a perfect adjustment in the working of the instrument .

112646

3701662

An Eighth Memoir on Quantics. [Abstract]

330

331

Proceedings of the Royal Society of London

A. Cayley

abs

6.0.4

proceedings

http://corpora.clarin-d.uni-saarland.de/surprisal/6.0.3/?id=112646