Crude  Vegetable  Drugs — Chemical  Changes, — Karl  Dieterich  has  studied
the  chemical  changes  that  occur  in  drugs  during  the  processes  which  they
undergo  before  being  put  on  the  market.  He  considers  these  under  four
divisions,  viz. :  (i)  those  drugs  which  are  usually  not  dried,  but  possess
their  maximum  efficacy  in  the  fresh  condition;  (2)  those  which  are  dried
to  augment  their  keeping  quahties,  and  which  necessarily  involve  a  chemi-
cal reaction;  (3)  those  in  which  drying,  besides  preserving,  either  causes
the  presence  or  increases  the  amount  of  active  ingredients ;  and  (4)  those
which  are  subjected  to  further  manipulation  in  order  to  give  them  a  valu-
able place  in  the  materia  medica.  He  infers  from  his  observations  that
oxidation  is  the  chief  factor  in  all  the  changes  that  do  occur,  whether  al-
lowed by  design  or  by  accident.  He  points  out  that  if  we  consider  the
differences  of  the  soil  from  which  plants  draw  their  nourishment,  and  if  we
consider  that  under  certain  circumstances  the  oxidation  will  be  carried
further  than  under  others,  we  need  not  wonder  at  the  lack  of  uniformity  in
the  same  drug  from  different  sources.  He  is  therefore  convinced  that  the
study  and  development  of  this  branch  of  pharmacy  will  yield  far  more
than  theoretical  results,  and  that  the  analysis  of  fresh  and  dried  drugs  at
different  stages  will  be  of  great  practical  advantage  in  directing  the  proper
manipulations  to  be  employed  in  producing  uniform  and  superior  products,
— Pharm.  Joum.,  June  19,  1897,  529-530;  from  Ber.  Deut.  Phar.  Ges.,
1896,  335-

Vegetable  Drugs — Histology  and  Pharmacognosy, — Alfred  R.  L.  Dohme
has  contributed  a  valuable  series  of  articles  upon  the  histology  and  pharma-
cognosy of  some  of  our  more  important  drugs  to  present  to  the  eye  of  the
pharmacist  pictures  of  these  drugs  drawn  by  him  from  nature,  as  they  ap-
pear under  the  microscope.  This  will  enable  them  to  be  distinguished
definitely  from  one  another,  and  hence  from  adulterations  and  foreign
admixtures.  In  connection  with  this  he  gives  the  various  organs  of  the
plant  wherever  possible,  and  those  characteristics  which  distinguish  them.
