the present invention embodies a method whereby the freshly removed representative oil sample is mixed with a solvent of selected composition and predetermined reagent concentration until a color intensity due to the contaminant concentration or ph value is achieved . this color intensity is manifest in a partitioned layer of the mixture which may be , for example , the lower phase of a two phase liquid system . most importantly , the present invention permits the above - described analysis to proceed in an aqueous medium and eliminates the need of performing the separate step of extracting the contaminants from the oil base before analysis . prior to the invention disclosed herein , it has been necessary to extract the contaminants from the oil by either reacting or complexing the contaminants with appropriate chemicals , removing the so extracted contaminants from the liquid system and thereafter performing analysis for the contaminant concentration . the present invention obviates the extraction by providing a suitable solvent and / or solvent - reagent solution with an aqueous base that effectively isolates the contaminant from the oil and permits an accurate determination of various color wavelengths and intensities in the aqueous layer with minimal interference from the generally opaque oil layer . as used herein , the expression , &# 34 ; freshly removed representative oil &# 34 ; refers to oil that has been removed from a running engine or machine for a short period of time such that a determination of the presence of contaminant material and / or active anti - corrosive additives therein is approximately indicative of concentrations and / or amounts of contaminant material and active anti - corrosive additives in the same oil remaining in the running engine or machine . as further used herein , &# 34 ; active anti - corrosive additive &# 34 ; is meant to include material added to the lubricating oil by the manufacturer which is capable of stabilizing the oil against the harmful increases of acidic and / or basic corrosive materials occurring during the operation of machines or engines in which the oil is placed . as also used herein , the phrase , &# 34 ; used oil &# 34 ; refers to oil which is in place in an operating machine or engine and from which the freshly removed representative oil is withdrawn . the phrase &# 34 ; unused lubricating oil &# 34 ; refers to oil that has not been placed in an operational machine or engine . it is preferred that the unused lubricating oil be eventually placed in the machine or engine in order to further standardize the analysis procedure . the reagents used in the practice of the present invention may be selected from a broad class of chemical compounds exhibiting oxidation - reduction , complexing , and / or acidic or basic properties . when analyzing for contaminants , the following reagents may be used : 1 , 10 - phenanthroline , zinc dithiol , chromotropic acid , phosphoric acid , sodium hydroxide , bathocuproine disulphonic acid disodium salt , α , α &# 39 ; dipyridyl , acetic acid , diphenyl carbazide , hydroxylamine hydrochloride , thioglycollic acid , and phosphomolybdic acid . when analyzing for corrosive material or active anti - corrosive additive , indicators such as thymol blue , methyl orange , methyl green , alizarin , benzopurpurin , 4 - β metacresol purple , and congo red - curcumin are useful . the solvents useful in the practice of the present invention may be a combination of chemicals having the ability to complex any contaminant material and / or active anti - corrosive additive existing in the freshly removed oil . as example , the solvent may be a combination of water , isopropyl alcohol ; water , phosphoric acid ; or water , sodium hydroxide , each in a ratio approximating 0 . 5 n : 1 n . the inorganic materials capable of being analyzed through the practice of the present invention would include those inorganic materials whose presence is made known by the operation of the machine itself . that is , the inorganic materials may be termed &# 34 ; wear metals &# 34 ; and would include those metals from which the machine is constructed such as , without limitation , iron , lead , copper , chromium , aluminum , nickel , silver , tin , silicon , boron , sodium , phosphorus , zinc , calcium , barium , magnesium , titanium , molybdenum , cadmium , vanadium and antimony . in the present invention , phosphorus is deemed to be a metal since it is often alloyed with one or more other metals for use in constructing machine components . in the present invention , the inorganic contaminants may be metal particles ( the size of which usually varies from generally equal to or greater than about 0 . 01 microns ) or the oxides of such metals . generally , when metal oxides are present they exist as surface layers on the particle surfaces . in this regard , the solvents of the present invention act to remove the inorganic contaminants from the oil by dissolving the metal oxides with the reagents thereafter reacting with or complexing the dissolved metal ions to form compounds exhibiting specific color characteristics . further , the solvents and reagents of the present invention may be pre - mixed as a solvent - reagent solution of predetermined solvent and reagent concentration . in order to establish reference points for the analysis of inorganic contaminants in freshly removed oil , organo - metallic standards may be used to provide concentration values selected as low , intermediate , and high values , such as for example 10 , 50 and 100 parts per million , for the specific metal contaminants present in the lubricating oil . for example , the organo - metallic standards may be standards commercially available from the conostan division of continental oil co ., ponca city , okla . and sold under the trademark conostan . such materials as these are generally regarded as appropriate standards for use in oil analyses . the method of the present invention in analyzing for inorganic contaminants proceeds as follows : a measured volume of a sample of freshly removed oil is placed in an appropriate receptacle such as , for example , a test tube capable of being tightly capped . a measured amount of solvent - reagent solution is added to the tube and thereafter , the sample tube is capped and shaken thoroughly . after shaking , the sample tube is placed in a vertical position to permit the freshly removed representative oil sample to separate from the solvent - reagent . the solvent - reagent phase , which may be found as the bottom layer of a 2 - phase liquid , exhibits a color intensity indicative of the contaminant material existing within the used oil . comparison of this color intensity with color intensity values obtained from practicing the method of the present invention on standard organo - metallic samples provides information indicative of the concentration of the contaminant material existing within the used oil . for example , the representative comparison value for metallic contaminants may be obtained in parts per million . the method of making the above - referenced comparisons is not critical to the present invention . accordingly , such comparisons may be made by standard spectrophotometric methods or by visually comparing the color intensity of the reacted oil sample with the color intensity generated by practicing the present invention on the organo - metallic standards . further , the comparison may also be made by visually comparing the oil - generated color intensity to a color chart which reproduces the color intensities generated by the organo - metallic standards . by testing samples of freshly removed oil at different times , one is thus able to derive data indicative of any increase in concentration of contaminant materials existing within the used oil . in order to further standardize the obtained analytical results , it is preferred that the method disclosed herein be first performed on an unused lubricating oil of the same type and grade that is subsequently to be placed in an operating machine or engine . the color intensity which is obtained from such unused lubricating oil testing may be compared to the standard organo - metallic color intensities in order to derive the approximate concentration of contaminant materials existing within the unused lubricating oil . it is also preferred that one or more analyses be performed on freshly removed oil after the lubricating oil has been placed within the operating environment of the machine or engine . whenever the subsequent analysis establishes that the contaminant level has exceeded a predetermined value , for example 100 parts per million , for a specific metal contaminant , the lubricating oil contains a sufficiently harmful concentration of contaminants to warrant replacement . as a further example , but without limitation , the method disclosed herein may be performed as follows : step 1 . place 4 . 5 ml of the selected solvent - reagent into a sample test tube capable of being capped ; step 2 . place 4 . 5 ml of freshly removed oil in the sample test tube used in step 1 , and cap the tube ; step 3 . shake the mixture resulting from step 2 thoroughly for approximately 15 seconds until the solution is well mixed ; step 4 . place the tube in a vertical position and allow to remain unattended for approximately 5 minutes or until the sample and solvent layers achieve separate phases ; step 5 . compare the color intensity in the lower layer of the liquid phase to the color intensity of the same phase obtained by performing steps 1 through 4 on an organo - metallic standard to obtain a comparison value indicative of the concentration in parts per million of the contaminant material existing within the lubricating oil . alternatively , the color intensity in the lower layer may be compared to a color chart which accurately reproduces the color intensities generated by the organo - metallic standards . table 1 provides examples of representative solvent - reagent combinations for the analysis of selected metal contaminants . table 1 . ______________________________________contaminant solvent reagent______________________________________iron hydroxylamine α , α &# 39 ; dipyridil hcl ; watercopper hydroxylamine bathocuproine hcl ; water disulfonic acid disodium saltchromium 85 % phosphoric chromotropic acid acid water disodium salttin water ammonium molybdatenickel water dimethylglyoxime disodium salt ; ammonium tartarate______________________________________ representative solvent and reagent systems for selected inorganic contaminant materials as noted from table 1 , analysis for nickel contaminant utilizes a dual reagent system with the water solvent dissolving any metallic oxides present in the oil . in the event oxides other than nickel are present such as , for example , iron , these oxides complex with the ammonium tartrate reagent to form an essentially colorless complex . accordingly , any nickel present complexes with the disodium salt of dimethylglyoxime to form a colored complex . the color intensity of this complex is measured to determine the concentration of nickel existing within the lubricating oil sample . as previously mentioned , oil manufacturers often add active anti - corrosive additives to the oil produced . these additives are useful in stabilizing the oil against the harmful effects created by increases in acidic and / or basic decomposition products which may be formed in the oil during operation of the machines or engines . in this regard , the anti - corrosive additives may be considered as buffers . however , as the acidic and / or basic decomposition products increase in concentration the buffering effect of the additives concommitantly decreases to a point where slight increase in the concentration of the acidic and / or basic products produces a rapid and extreme change in the ph of the lubricating oil . accordingly , the acidic or basic environment produced by this change warrants replacement of the oil with unused lubricating oil . the method of the present invention of determining the presence and concentration of active anti - corrosive additives proceeds as follows : a measured volume of a sample of freshly removed oil is placed in an appropriate receptacle such as , for example , a test tube capable of being tightly capped . a measured amount of solvent - reagent solution is added to the tube and thereafter , the sample tube is capped and shaken thoroughly . after shaking , the sample tube is placed in a vertical position to permit the freshly removed representative oil sample to separate from the solvent - reagent . the solvent - reagent phase , which may be found as the bottom layer of a 2 - phase liquid , exhibits a color indicative of the ph of the oil and further indicative of the concentration of the anti - corrosive additive existing within the used oil . comparison of this color with color values obtained from practicing the method of the present invention on unused lubricating oil samples provides information indicative of the change of ph of the representative sample of freshly removed lubricating oil , hence the change of ph of the oil then in use in the machines or engines . for example , the representative comparison value may be obtained in ph units . the method of making the above - referenced comparisons is not critical to the present invention . accordingly , such comparisons may be made by standard spectrophotometric methods or by visually comparing the color of the reacted oil sample with the color generated by practicing the present invention on the unused oil . further , the comparison may also be made by visually comparing the oil - generated color with a color chart which reproduces the color generated by the unused oil . by testing samples of freshly removed oil at different times , one is thus able to derive data indicative of any change in ph , hence concentration of anti - corrosive additive existing within the used oil . for example , a change in the ph value towards a value of approximately ph 2 represents an increase of acidic corrosive materials in the lubricating oil and a corresponding decrease in the concentration of the active anti - corrosive additive in the lubricating oil . a change in ph value toward a value of ph 10 represents an increase in active anti - corrosive additive concentration and / or an increase in basic contaminant material in the lubricating oil . additionally , an increase in ph towards 10 may also indicate further contamination of the lubricating oil . for example , in certain industries such as the petrochemical industry , machines or engines are used in corrosive atmospheres . in these atmospheres , gaseous materials such as , for example , ammonia may be absorbed by the oil . in this event , the gaseous materials may react with other contaminants in the oil or with water to produce basic compounds which effect the ph of the lubricating oil . in order to further standardize the obtained analytical results , it is preferred that the method disclosed herein be first performed on an unused lubricating oil of the same type and grade that is subsequently to be placed in an operating machine or engine . the color which is obtained from such unused lubricating oil testing may be further compared to the colors generated by practicing the present invention on standardized acidic and / or basic solutions . it is also preferred that one or more analyses be performed on freshly removed oil after the lubricating oil has been placed within the operating environment of the machine or engine . whenever the subsequent analysis establishes that the ph level has exceeded the norm for the specific oil in use , the concentration of the anti - corrosive additive has decreased sufficiently to warrant replacement of the oil . as a further example , but without limitation , the method disclosed herein may be performed as follows : step 1 . place 4 . 5 ml of the selected solvent - reagent into a sample test tube capable of being capped ; step 2 . place 4 . 5 ml of freshly removed oil in the sample test tube used in step 1 , and cap the tube ; step 3 . shake the solution resulting from step 2 thoroughly for approximately 15 seconds until the solution is well mixed ; step 4 . place the tube in a vertical position and allow to remain unattended for approximately 5 minutes or until the sample and solvent layers achieve separate phases ; step 5 . compare the color in the lower layer of the liquid phase to the color of the same phase obtained by performing steps 1 through 4 on a representative sample of unused oil to obtain an comparison value indicative of the ph of the freshly removed oil and further indicative of the decrease in concentration of the anti - corrosive additive . furthermore , distilled water is an appropriate solvent to use in the practice of this method . the solvent dissolves organic acids , mineral acids and bases , and acidic and / or basic salts that may exist in the lubricating oil sample . additionally , colorimetric reagents such as , for example , a mixture of thymol blue and methyl orange are useful . such mixture permits the determination of the ph of the oil sample from a ph of approximately 2 to a ph of about 10 by providing a reagent which changes color depending upon the ph of the oil . table 2 provides an example of a typical solvent - reagent system together with the absorbance for varying ph values . table 2 . ______________________________________solvent - 468 ml distilled waterreagent - 35 ml thymol blue ; 7 ml methyl orangeph absorbance ( mμ ) ______________________________________2 490 - 500 ( red ) 4 480 - 490 ( orange ) 6 435 - 480 ( yellow ) 9 560 - 595 ( violet ) ______________________________________ representative absorbance values for varying ph values of a typical solventreagent system for ph determination . in order to establish the efficacy of the invention disclosed herein a series of experiments are performed on oil samples removed from an operational engine . table 3 provides the parameters of the operational environment of this engine and certain additional chemical data . table 3 . ______________________________________ oil sample data and chemical analysis of oil re - moved from an oil pumping station at alden , kansas ( michigan - wisconsin pipeline ). sample data sample analysis______________________________________ engine # 309 - ir viscosity @ 100 ° f ., sus 752data sampled 7 - 21 - 77 viscosity @ 210 ° f ., sus 78 . 2oil hdg - 30 viscosity increment 16 . 0 @ 210 ° f ., % oil hours 2926 tan . sup . 1 , mg koh / g 7 . 7______________________________________ 1 . total acid number ; a tan value of 7 . 7 is approximately equal to a ph of 3 . 5 to 4 . 0 . a solvent is prepared by dissolving 15 . 0 g hydroxylamine hydrochloride in 500 ml h 2 o ( distilled ). to this solvent is added 5 . 0 g of the reagent α , α ,&# 39 ; dipyridil . approximately 4 . 5 ml of freshly removed oil is placed in a test tube containing approximately 4 . 5 ml of the solvent - reagent solution . the test tube is capped and vigorously shaken for about 15 seconds and then permitted to stand in a vertical position for about 90 minutes . the mixture , upon standing , separates into two layers or phases with the solvent - reagent phase as the lower layer and the oil phase as the upper layer . the lower layer displays a color , with an absorbance measured in the range of approximately 520 - 522 mμ . comparison of the color intensity of this sample with that obtained from performing this procedure on an iron organo - metallic standard containing a known amount of iron indicates the freshly removed oil sample contains approximately 60 parts per million iron . table 4 presents data obtained from an emission spectrograph analysis performed on a sample of the freshly removed oil used in this example . reference to this table indicates that the sample contains approximately 70 ppm iron as a contaminant , thus establishing the reliability of the procedure disclosed herein . table 4 . ______________________________________ emission spectrograph data obtained from the oilsample of table 3 . metal concentration , ppm______________________________________iron 70copper 178 * ( 50 ) chromium 5tin 9______________________________________ * this value was believed to be erroneous and a second emission spectrograph was run . the results of this second run are presented paranthetically . a solvent is prepared by dissolving 15 . 0 g hydroxylamine hydrochloride in 500 ml h 2 o ( distilled ). to this solvent is added 0 . 5 g of the reagent bathocuproine disulfonic acid disodium salt . approximately 4 . 5 ml of freshly removed oil is placed in a test tube containing approximately 4 . 5 ml of the solvent - reagent solution . the test tube is capped and vigorously shaken for about 15 seconds and then permitted to stand in a vertical position for about 90 minutes . the mixture , upon standing , separates into two layers or phases with the solvent - reagent phase as the lower layer and the oil phase as the upper layer . the lower layer displays a color , with an absorbance meansured in the range of approximately 476 - 479 mμ . comparison of the color intensity of this sample with that obtained from performing this procedure on a copper organo - metallic standard containing a known amount of copper indicates the freshly removed oil sample contains approximately 70 parts per million iron . table 4 indicates that initial emission spectrographs establishes the sample contains approximately 178 ppm copper as a contaminant , however , a second emission spectrograph analysis shows the initial value to be erroneous . the second spectrograph indicates the cu concentration to be in the range of 50 ppm . a solvent is prepared by dissolving 5 . 0 ml . chromotropic acid disodium salt in 495 ml h 2 o ( distilled ). to this solvent is added 25 . 0 g of the reagent 85 % phosphoric acid . approximately 4 . 5 ml of freshly removed oil is placed in a test tube containing approximately 4 . 5 ml of the solvent - reagent solution . the test tube is capped and vigorously shaken for about 15 seconds and then permitted to stand in a vertical position for about 90 minutes . the mixture , upon standing , separates into two layers or phases with the solvent - reagent phase as the lower layer and the oil phase as the upper layer . the lower layer displays a color , with an absorbance measured in the range of approximately 542 - 540 mμ . comparison of the color intensity of this sample with that obtained from performing this procedure on a chromium organometallic standard containing a known amount of chromium indicates the freshly removed oil sample contains less than 10 parts per million chromium . reference to table 4 indicates the oil contains approximately 5 ppm chromium . a solvent - reagent solution is prepared by dissolving 12 . 5 g ammonium molybdate in 500 ml h 2 o ( distilled ). approximately 4 . 5 ml of freshly removed oil is placed in a test tube containing approximately 4 . 5 ml of the solvent - reagent solution . the test tube is capped and vigorously shaken for about 15 seconds and then permitted to stand in a vertical position for about 5 minutes . the mixture , upon standing , separates into two layers or phases with the solvent - reagent phase as the lower layer and the oil phase as the upper layer . the lower layer displays a color , with an absorbance measured in the range of approximately 715 - 840 mμ . comparison of the color intensity of this sample with that obtained from performing this procedure on a tin organometallic standard containing a known amount of tin indicates the freshly removed oil sample contains less than 10 parts per million iron . reference to table 4 shows the oil contains approximately 9 ppm tin . comparison of the spectrograph result with the result of the procedure disclosed herein establishes the efficacy of the present invention . a solvent - reagent solution is prepared by dissolving 7 ml of methyl orange and 35 ml of thymol blue in 468 ml of distilled water . approximately 4 . 5 ml of freshly removed oil is placed in a test tube containing about 4 . 5 ml of the solvent - reagent solution . the tube is capped and vigorously shaken for about 15 seconds and then permitted to stand in a vertical position for about 5 minutes . the mixture , upon standing , separates into two layers or phases with the solvent - reagent phase as the lower layer and the oil phase as the upper layer . the lower layer displays a color , with an absorbance measured in the range of approximately 482 mμ . comparison of the color intensity of this sample with that obtained from performing this procedure on an active anti - corrosive additive standard with a known ph value indicates the freshly removed oil sample has a ph value of about 5 . the method of the present invention may be easily practiced by a person who has not previously received training normally associated with a chemist or highly skilled technician . to this end , the invention also provides a lubricating oil analysis kit 10 as shown in fig1 with the components of the kit being preselected by the manufacturer to permit analysis for one or more contaminant materials . preferably , the kit of the present invention contains at least one receptacle 12 adapted to be closed on one end 14 thereof and of sufficient volume to hold approximately 5 ml of solvent - reagent and approximately 5 ml of lubricating oil . preferably , each receptacle , prior to receipt by the user , contains a pre - determined volume of a preselected solvent - reagent solution adapted for analysis of a specific contaminant . for example , the receptacle may be a 30 ml volume test tube externally threaded on the open end thereof and adapted to receive a threaded cap 16 thereupon . further , it is preferred that the solvent - reagent solution be pre - mixed by the manufacturer thereof , with the solution being stored in a capped receptacle during shipment . also included in the kit is a dispensing device 18 for measuring a known volume of freshly removed oil and for adding the measured volume to the solvent - reagent containing receptacle . such apparatus may , for example , be a graduated buret or an eye - dropper - type device of known voume . alternatively , the above - referenced receptacle may be graduated as indicated by line 20 such that addition of the oil to the receptacle may be carried out until a known amount of lubricating oil is added thereto . it is preferred to assure that the dispensing device does not become contaminated during shipment of the kit , and prior to use thereof . accordingly , the device may be sealed , such as in a plasticized wrapper or in an empty receptacle such as that used to contain the solvent - reagent solution . in using the kit of the present invention , the user first obtains a representative sample of freshly removed oil . thereafter , a volume of the oil is obtained by withdrawing the volume with the dispensing device . the volume is then placed in the receptacle containing the solvent - reagent solution until a known volume of oil has been added . analysis thereafter proceeds as previously described . in order to enable the user to accurately determine the concentration of contaminant materials existing in the freshly removed oil sample , and to obviate the need for the user to establish standardized color intensities by performing the method of the invention on organo - metallic and / or ph standards , the kit is provided with a color chart 22 that accurately reproduces the color intensities for varying concentrations of the several metallic , acidic , and basic contaminants . for example , for each specific metallic contaminant analyzable by the present invention , the color chart may provide representative color intensities for one or more concentration levels , such as 10 , 50 and 100 parts per million . thus , after the color is generated for each metal contaminant tested , the intensity is compared to the appropriate color chart intensity level to determine the approximate level of contaminant concentration . determination of the ph of the oil sample proceeds in the same fashion . while the invention has been described with reference to preferred embodiments , alternatives thereto and certain examples , it should be realized that one skilled in the art may make modifications or changes to the invention while still falling within the scope and spirit of the disclosure . accordingly , all such modifications or changes should be deemed to be a part hereof . for example , in the various examples provided herein one volume of solvent - reagent solution is mixed with an approximately equal volume of freshly removed oil sample . one skilled in the art will readily appreciate that this ratio is variable depending on the solvent and reagent concentrations and , therefore , the examples are not meant to be limiting in any manner .