Estimation  of  Morphine  in  Opium.  635 
solution,  and  it  is  evaporated  without  stirring.  The  residue  is  treated 
with  60  grams  of  cold  water,  and  decanted  into  a  glass  cylinder ;  the 
clear  liquid  is  poured  off,  and  the  undissolved  portion  washed  again 
with  30  grams  of  cold  water,  and  then  with  45  grams  of  alcohol  (90 
per  cent.),  and  finally  collected.  The  crystalline  mass  remaining  on 
the  filter  is  dried  between  filter-paper,  dissolved  in  15  grams  of  acetic 
acid  (1  part  of  acid  sp.  gr.  1*06  to  8  parts  of  water)  and  15  grams  of 
distilled  water,  and  then  filtered  through  the  same  paper  on  which  the 
residue  was  collected.  The  filtrate  is  treated  with  ammonia,  and  the 
precipitate  is  collected  and  weighed  after  standing  for  1 2  hours. 
The  author  has  devised  the  following  method :  10  to  20  grams  of 
the  opium  to  be  examined  are  boiled  for  a  short  time  with  15  to  30 
grams  of  caustic  baryta  and  about  150  to  200  cc.  water.  The  mix- 
ture is  then  filtered,  and  the  residue  repeatedly  boiled  with  small 
quantities  of  water  until  the  solution  fails  to  give  a  reaction  with 
molybdic  acid  and  sulphuric  acid.  Excessive  boiling  is  to  be  avoided, 
and  as  a  rule  the  filtrate  should  not  amount  to  more  than  400-500  cc. 
A  stream  of  carbonic  anhydride  is  passed  into  this  solution,  which  con- 
tains all  the  morphine,  until  the  liquid  is  supersaturated,  and  then  the 
whole  is  evaporated  on  a  water-bath  as  quickly  as  possible.  The  resi- 
due is  moistened  with  absolute  alcohol,  transferred  to  an  Erlenmeyer's 
flask,  and  exhausted  with  successive  quantities  of  boiling  absolute 
alcohol  until  a  sample  evaporated  on  a  watch-glass  no  longer  gives  a 
morphine  reaction.  This  usually  requires  from  300  to  400  cc.  alcohol. 
The  alcohol  is  removed  by  distillation,  and  the  residue  left  in  the 
flask  is  allowed  to  stand  for  some  time  with  1 5  cc.  of  ammonia.  It  is 
next  collected  on  a  tared  filter,  dried  at  40°,  and  treated  repeatedly 
with  chloroform.  This  is  the  crude  morphine.  It  should  be  light- 
brown  to  straw-colored.  Crude  morphine  generally  contains  substances 
which  can  be  classed  under  two  heads,  namely,  (1)  those  which  are 
insoluble  in  acetic  acid ;  (2)  those  which  are  soluble,  but  which  are 
reprecipitated  by  ammonia  and  potassium  ferrocyanide.  The  author 
finds  that  the  amount  of  the  impurities  is  always  small,  and  that  the 
difference  between  the  crude  and  the  pure  morphine  is  principally  due 
to  the  loss  of  morphine  in  the  process  of  purification.  The  following 
table  gives  the  percentages  of  morphine  found  by  employing  the  vari- 
ous methods.    The  impure  products  are  marked  thus*. 
Am.  Jour.  Pharm.") 
Dec,  1884.  j 
