2/0 
Preparation  of  Nux  Vomica. 
Am.  Jour.  Pharm. 
April,  1921. 
tttes,  the  control  of  the  gravimetric  result  previously  obtained.  In 
addition  to  this,  in  the  special  case  where  the  extract  of  nux  vomica 
would  not  be  perfectly  freed  from  oil,  or  again  if  a  tincture  of  nux 
vomica  prepared  directly  by  alcoholic  percolation  had  to  be  titrated, 
without  passing  through  the  cleaned  extract,  the  figure  to  retain 
would  be  the  volumetric  result  obtained  after  filtration  on  a  wet- 
ted filter  and  elimination  of  the  enclosed  oil  by  ether-chloroform 
during  the  extraction  of  the  alkaloids ;  the  indicator  reagent  should 
always  be  the  tincture  of  litmus  to  the  exclusion  of  all  others. 
The  choice  of  the  indicator  reagent  should  not  be  taken  with  in- 
difference.   In  fact,  experience  shows : 
i.  That  cochineal,  helianthine  and  muscari  give  figures  much 
higher  than  the  reality.  2.  That  phtaleine  begins  to  turn  only  at 
the  moment  where  the  greater  part  of  the  alkaloids  has  been  titrated. 
3.  That  iodeosine,  with  which  the  change  of  color  is  clear  enough, 
although  difficult  to  appreciate,  is  practically  not  to  be  found  in  a 
pure  state. 
It  is  then  to  the  tincture  of  litmus  that  preference  has  to  be 
given.  In  my  method,  the  results  are  expressed  in  pure  strychnine 
(coefficient  334)  ;  but  nux  vomica  and  St.  Ignatius  bean  contain  at 
the  same  time  strychnine  and  brucine,  associated  in  variable  propor- 
tions. The  coefficient  334  that  I  have  chosen  is  not  then  more  exact, 
a  priori,  than  the  coefficient  364,  proposed  at  the  same  time  by  the 
French  Codex  and  by  Gilkinet,  as  corresponding  to  an  equal  weight 
of  strychnine  and  brucine.  Have  the  authors  who  have  busied 
themselves  with  this  question  exhausted  the  nux  vomica  and  have 
they  assured  themselves  that  strychnine,  much  less  soluble  than 
brucine,  requires  a  much  greater  time  in  order  to  pass  completely 
into  solution? 
By  prolonged  macero-lixiviation,  there  is  obtained  after  thirty 
days'  treatment,  an  almost  insipid  percolate,  which  corresponds  to  a 
then  nearly  complete.  The  extract  of  nux  vomica  prepared  under 
these  conditions,  should  therefore  include  almost  the  entire  amount 
&f  strychnine  contained  in  the  seed.   Now  the  gravimetric  determina- 
dilution  of  about 
1 
,  expressed  in  strychnine;  the  exhaustion  is 
500,000 
