6  Estimation  of  Strychnine  in  Nux  Vomica.    { A™aSaryfi907.m' 
third  alkaloid  in  nux  vomica  it  may  not  be  a  negligible  factor  so  that 
deductions  from  experiments  with  pure  alkaloids  cannot  wholly 
be  applied  to  the  total  alkaloids  obtained  in  the  usual  way. 
Different  portions  of  10  c.c.  of  the  fluid  extract  (mentioned  before) 
were  operated  on  by  the  usual  method  until  the  total  alkaloids  were 
obtained.  These  were  subjected  to  the  process,  detailed  below,  then 
the  alkaloidal  residue  was  extracted  and  titrated.  To  overcome  the 
objections  to  experimenting  with  unknown  quantities  of  alkaloids, 
and  to  thoroughly  test  the  process,  the  alkaloid  was  again  extracted 
after  the  above  nitration,  subjected  a  second  time  to  the  nitrifying 
agent  under  same  conditions  as  before,  then  extracted  and  titrated. 
The  results  are  given  below. 
Alkaloid 
Alkaloid      obtained  on 
Temp.  Time.         recovered,  repeating. 
1.  Alkaloids  from  10  c.c.  F.  E.    650  F.        30  min.    0*1068  gm.  0*1063 
2.  Alkaloids  from  10  c.c.  F.  E.    900  F.         30  "       0*1066  gm.  0*1054 
3.  Alkaloids  from  10  c.c.  F.  B.    780  F.         10  "       o*io68  gm.  not  repeated. 
The  process  was  then  applied  to  the  fluid  extract  of  nux  vomica 
without  preliminary  extraction  of  the  alkaloids,  10  c.c.  was  evaporated 
to  dryness  in  a  beaker.  The  resulting  extract  was  dissolved,  as  far 
as  possible,  in  15  c.c.  3  per  cent.  H2S04  and  treated  with  nitric  acid 
and  sodium  nitrate  in  the  usual  way.  At  end  of  30  minutes  the  mix- 
ture was  diluted  with  20  c.c.  water,  run  through  a  pledget  of  cotton 
wool,  then  filtered  and  followed  by  wash  water.  The  bulked  liquid 
was  put  in  a  separator,  made  alkaline  with  KOH  solution,  and 
extracted  by  means  of  chloroform.  The  alkaloid  was  obtained  in 
definite  crystals  having  a  yellow  tinge,  but  otherwise  free  from 
impurity.  The  titration  indicated  0*1072  gramme,  which  closely 
agrees  with  figures  above. 
Evidently,  then,  the  process  is  not  affected  by  the  purity  of  the 
alkaloidal  residue.  We  have  already  shown  that  it  is  applicable 
over  a  wide  range  of  temperature,  and  is  not  affected  by  any  possible 
manner  of  adding  the  reagents  or  probable  impurity  therein.  Sub- 
sequent  use  in  the  routine  work  of  the  laboratory  justifies  these 
conclusions. 
Adding  our  modifications  to  the  text  of  the  U.S. P.,  the  following 
gives  the  process  in  detail : — 
— "  dissolve  the  alkaloidal  residue  in  1 5  c.c.  of  3  per  cent.  H2S04. 
To  this  solution  add  3  c.c.  of  a  mixture  of  equal  volumes  of  nitric 
