SOLUTION  OF  MECONATE  OF  MORPHIA. 
105 
If  it  be  desirable  to  represent  tbe  thebolactic  acid  in  this  solu- 
tion, it  will  be  necessary  to  prepare  the  acid  by  a  separate  pro- 
cess, as  this  acid  is  not  precipitated  by  acetate  of  lead  or  ammo- 
nia. The  proportion  of  meconic  acid  in  opium,  according  to  the 
best  authorities,  is  about  5  per  cent. ;  that  of  thebolactic  acid  2 
per  cent.  {See  Amer.  Jour.  Pharm.  for  1865,  p.  466.) 
In  glancing  over  the  meconates,  with  a  view  to  the  selection 
of  one  that  would  render  the  use  of  sulphuretted  hydrogen  un- 
necessary, I  concluded  to  try  the  baryta  salt,  as  recommended 
by  Couerbe,  for  the  preparation  of  meconic  acid.  This  consists 
in  making  a  solution  from  the  opium  in  powder,  with  alcohol 
90°,  precipitating  this  with  powdered  chloride  of  barium  in  ex- 
cess, observing  accurately  the  quantity  used,  separating  the 
precipitate,  washing  it  with  strong  alcohol,  mixing  it  with  hot 
water,  and  adding  a  quantity  of  sulphuric  acid.,  properly  diluted, 
equivalent  to  the  baryta  present,  filtering  the  liquid  while  hot  to 
avoid  loss  of  meconic  acid  by  cooling.  The  alcoholic  morphia 
liquid  was  then  distilled  to  recover  the  alcohol,  treated  with 
water,  filtered,  half  its  bulk  of  the  recovered  alcohol  added,  pre- 
cipitated by  ammonia,  allowed  to  stand  until  the  impure  morphia 
had  separated,  and  this  collected  and  washed,  added  to  the  me- 
conic acid,  dissolved  by  a  gentle  heat,  and  filtered. 
This  process  cannot  be  recommended,  however,  for  the  shop, 
as  it  involves  too  much  nicety  of  manipulation  in  adding  and 
separating  the  baryta,  occupies  too  much  time,  and  retains  the 
opium  odor  more  firmly,  unless  the  alcoholic  extract  be  dried  and 
re-dissolved  by  water  before  precipitating  the  morphia. 
The  following  working  process  is  therefore  suggested  as  more 
eligible  for  the  apothecary,  and  as  being  less  complicated : 
Take  of  Opium  in  powder  (or  dry  enough  to  powder),  5  troyounces, 
Stronger  Alcohol  (95  per  cent.),  a  pint, 
Distilled  Water, 
Water, 
Acetate  of  Lead, 
Water  of  ammonia,  of  each  a  sufficient  quantity, 
Ingredients  for  generating  sulphuretted  hydrogen,  a 
sufficient  quantity. 
