36  Assay  of  Opium.  {^JEfrJSSr 
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Dartmouth  College. 
A  NOTE  ON  THE  ASSAY  OF  OPIUM. 
By  William  R.  Lamar. 
Recently  the  writer,  while  engaged  in  assaying  a  sample  of  pow- 
dered opium,  according  to  the  U.S.P.  method,  noticed,  after  having 
exhausted  the  opium  and  concentrated  these  aqueous  liquids  to  14 
grammes ;  and  after  its  transferrence  to  a  tared  Erlenmeyer  flask, 
the  weight  then  brought  up  to  20  grammes,  with  the  rinsings  of  the 
capsule,  had  been  accomplished,  that  the  addition  of  the  prescribed 
10  grammes  of  alcohol  caused  a  very  pronounced  flocculent  precip- 
itate. 
This  precipitate,  after  the  addition  of  25  c.c.  of  ether,  shaking 
actively,  and  allowing  to  stand  for  a  few  minutes,  did  not  apprecia- 
bly diminish. 
At  the  time,  it  was  considered  quite  likely  that  the  solution  of 
this  deposited  matter,  upon  the  further  addition  of  the  ammonia 
water,  might  not  be  effected,  and  would  therefore  contaminate  the 
precipitate,  to  be  subsequently  weighed  as  morphine. 
This  in  reality  seems  to  be  the  case,  as  shown  by  the  weight  of 
the  crude  morphine,  and  of  the  matter  insoluble  in  lime  water. 
It  was  believed  that  by  increasing  the  amount  of  the  alcohol,  all 
of  this  objectionable  matter  in  solution  could  be  gotten  rid  of  prior 
to  the  precipitation  of  the  morphine. 
With  this  end  in  view,  a  series  of  experiments  was  instituted, 
which  resulted  in  the  confirmation  of  this  view,  as  will  be  seen  from 
the  analytical  data  to  follow. 
As  the  result  of  his  experiments,  the  writer,  therefore,  recom- 
mends the  following  modification  of  the  U.S.P.  process: 
