48  ASSAY  OF  MORPHIA  IN  OPIUM. 
The  quantity  of  morphia  is  determined  in  the  remaining  two- 
thirds  of  liquor,  which  represents  ten  grammes  of  opium. 
To  the  liquor  is  added  an  equal  volume  of  rectified  spirit  and 
a  quantity  of  ammonia,  exactly  double  that  used  in  the  first  ex- 
periment. (It  is  necessary  to  add  a  slight  excess  of  ammonia, 
to  obtain  the  complete  separation  of  the  morphia.)  The  liquid 
is  then  agitated,  and  allowed  to  stand  in  a  well-closed  flask.  It 
soon  deposits  crystals,  some  in  fine  needles,  very  little  colored, 
which  is  narcotine  ;  the  others  in  prisms,  more  bulky,  and  a  little 
more  colored,  are  morphine.  After  two  or  three  days  the  flask 
is  well  agitated,  and  allowed  to  stand  again  for  some  hours,  to 
give  the  morphia  time  to  precipitate  completely.  The  crystals 
are  then  collected  upon  a  small  filter,  and  washed  with  about  half 
an  ounce  of  proof  spirit.  This  washing  removes  the  mother- 
liquor  and  the  coloring  matter.  There  remain  on  the  filter  crys-» 
tals  of  morphine,  which  are  slightly  colored,  and  crystals  of  nar- 
cotine, which  are  colorless.  The  filter  is  dried  upon  the  same 
funnel,  two  or  three  drachms  of  ether  added,  and,  after  that,  three 
or  four  drachms  of  chloroform  at  twice.  The  crystals  of  narco- 
tine instantly  dissolve  in  the  chloroform,  and  are  removed  with 
it.  The  chloroform  does  not  affect  the  morphia.  The  filter  is 
finally  washed  with  three  drachms  of  ether,  to  remove  the  last 
traces  of  chloroform  and  "narcotine,  and  then  dried.  The  crys- 
tals of  morphia,  which  are  removed  with  great  facility,  are 
weighed. 
In  the  process  which  I  have  just  described,  in  treating  the 
opium  with  water,  all  the  morphia  which  exists  in  combination 
is  easily  dissolved  with  very  little  narcotine  and  a  little  resin  ous 
and  coloring  matter.  If  ammonia  be  added  to  the  aqueous  solu- 
tion, a  dirty  precipitate  is  obtained  of  morphia,  narcotine,  and 
coloring  matter.  The  addition  of  the  alcohol  retards  the  pre- 
cipitation of  the  alkaloids,  and  gives  them  time  to  assume  the 
crystalline  form.  The  alcohol  also  retains  in  solution  the  resin- 
ous and  coloring  matter.  Nearly  colorless  crystals  are  therefore 
obtained. 
Washing  the  morphia  with  chloroform  is  a  very  simple  opera- 
tion, which  completely  separates  all  the  narcotine. — London 
Pharmaceutical  Journal,  November,  1857. 
