Ain.^our.jiiarm.j        Detectiou  of  Strychnliie  and  otlm^  Alkaloids.  397 
tartaric  acid  is  added  and  the  whole  distilled.  When  the  bulk  of  the 
alcohol  is  distilled  off,  the  remainder  is  expelled  by  evaporation  to 
dryness  on  the  water-bath,  the  residue  is  taken  up  with  a  little  boiling 
water,  and  left  to  cool  in  order  to  separate  the  fat.  The  filtrate,  which 
should  be  about  20  to  25  cc,  is  made  decidedly  alkaline  with  soda  and 
transferred  to  a  large  watch-glass,  mixed  with  gypsum,  allowed  to  set, 
powdered,  dried  in  an  exsiccator,  and  then  extracted  with  chloroform 
in  a  large  Soxhlet's  apparatus.  The  chloroform  extract  is  brought  to 
a  small  volume,  10  to  15  cc,  filtered  if  necessary,  and  the  extract 
treated  with  an  equal  volume  of  a  saturated  solution  of  oxalic  acid  in 
ether.  Fine  acicular  crystals  of  strychnine  oxalate  soon  appear ;  the 
oxalate  is  collected  on  a  filter,  washed  with  a  mixture  of  equal  parts  of 
alcohol  and  chloroform,  dried  and  dissolved  in  the  least  possible  quan- 
tity of  water,  and  the  strychnine  precipitated  by  addition  of  ammonia. 
By  this  method,  the  author  has  recovered  strychnine  from  a  frog 
killed  by  a  subcutaneous  injection  of  0*01  gram,  from  the  liver  of  a 
rabbit  killed  by  subcutaneous  injection  of  0'04  gram  of  the  sulphate, 
and  from  the  stomach  of  a  cat  killed  by  eating  flesh  containing  0*03 
gram  of  strychnine. 
Experiments  show  the  process  to  be  very  accurate.  As  chloroform 
is  a  solvent  of  most  vegetable  alkaloids,  it  is  evident  that  this  process 
or  a  slight  modification  of  it  can  be  used  for  the  isolation  of  such  of 
them  as  are  precipitated  by  an  ethereal  solution  of  oxalic  acid.  The 
author  made  experiments  with  brucine,  narceine,  papaverine,  thebaine, 
morphine,  aconitine,  atropine,  hyoscyamine,  veratrine,  nicotine,  conine, 
and  colchicine,  two  of  these,  morphine  and  colchicine,  were  not  soluble 
in  chloroform,  the  others  were  completely  precipitated  as  oxalates. 
The  precipitate  took  some  hours  to  form  in  the  case  of  strychnine, 
brucine,  narceine,  codeine,  nicotine,  and  conine,  for  the  remainder  24 
hours  were  necessary.  The  precipitate  was  crystalline  in  every  case 
except  that  of  aconitine,  which  was  amorphous. 
In  the  case  of  brucine,  nicotine,  veratrine,  and  atropine,  which  are 
not  completely  precipitated  by  ammonia,  the  oxalate  is  dissolved  in 
alcohol,  the  oxalic  acid  is  precipitated  by  a  little  alcoholic  potash, 
filtered  off,  and  the  potash  removed  by  a  stream  of  carbonic  anhydride; 
after  frequent  filtration,  the  alcohol  is  allowed  to  evaporate  sponta- 
neously, and  the  pure  alkaloid  remains. — Jour.  Chem.  Soc,  May,  1885, 
p.  605;  from  Zeit.  Physiol.  Chem.,  [9],  40-48. 
