256  Quantitative  Estimation  of  Strychnine.    {Am jJu0ner;imrm' 
the  atomic  weights  of  strychnine  and  brucine),  as  the  amount  of 
alkaloid  in  milligrammes  neutralized  by  1  c  c.  of  the  acid. 
This  gave  total  alkaloid  as  19  9  per  cent.  pure.  The  remaining 
half  I  treated  according  to  the  above  method,  and  the  weight  of  the 
residue,  which  was  perfectly  white,  gave  the  amount  of  strychnine 
as  7  96  per  cent.  The  proportion  of  strychnine  in  the  total  alkaloid 
was,  therefore,  40  per  cent. 
Naturally,  having  taken  for  a  titration  factor  a  figure  based  on 
50  per  cent,  strychnine  in  total  alkaloids,  there  will  be  a  slight  dis- 
crepancy here ;  but,  as  that  is  the  figure  generally  taken,  I  have 
always  used  it. 
Tile  strong  reserve  percolate  of  a  fluid  extract  was  the  next  to  be 
assayed. 
This  yielded  impure  alkaloids  2-3  per  cent. 
As  before,  one-half  of  this  residue  was  titrated  and  yielded  1-96 
per  cent,  pure  total  alkaloid. 
The  strychnine  found  was  calculated  to  0-88  per  cent.  This 
shows  a  proportion  of  45  per  cent,  strychnine  in  total  alkaloid. 
Next,  some  new  drug  was  examined  and  was  treated  by  Lyons's 
method,  No.  360  in  " Assay  of  Drugs." 
The  impure  alkaloid  from  10  grammes  weighed  0-32  gramme  = 
3-2  per  cent. 
n 
This  was  dissolved  in  20  c.c.  -  H9S0,  and  half  titrated  as  before. 
2 
The  result  was,  total  pure  alkaloid  2-9  per  cent.  The  colorless 
strychnine  obtained  from  the  other  half  of  this  solution  weighed 
0-0635  gramme  =  1*27  per  cent,  and  44  per  cent,  of  the  total 
alkaloid. 
From  I  gramme  of  a  solid  extract  of  nux  vomica  an  impure 
alkaloid  was  obtained  which  weighed  0-162  gramme  =  16-2  per 
cent. 
On  titration  this  yielded  15-1  per  cent,  total  pure  alkaloid.  Half 
of  this  solution  was  also  used  for  estimation  of  strychnine,  which 
weighed  0-0332  gramme  =  6-64  per  cent,  and  44  per  cent,  of  the 
total  alkaloid. 
This  solid  extract  was  made  from  the  same  drug  previously  men- 
tioned, and  it  will  be  noticed  that  the  proportion  of  strychnine 
obtained  is  in  each  case  identical,  which  proves  the  reliability  of 
the  method.  For  convenience  and  comparison  these  results  are 
tabulated  below. 
