112 
ON  SOLUTION  OF  CITRATE  OF  MAGNESIA. 
Pharm.  xxxviii.,  472),  it  requires  1285  parts  of  cold  water,  945 
parts  of  alcohol  of  80  per  cent.,  and  800  parts  of  diluted  acetic 
acid  to  dissolve  it.  Liebig  gives  its  solubility  in  cold  water  at 
375.  Acetic  acid  is  not  a  good  solvent  for  narceia ;  in  fact  the 
acetate  of  narceia,  like  the  acetate  of  quinia,  is  quite  insoluble, 
and  is  instantly  precipitated  by  mixing  solution  of  acetate  of  am- 
monia with  solution  of  hydrochlorate  of  narceia.  The  narceia 
should  be  triturated  with  a  little  water  before  adding  the  muri- 
atic acid,  because  the  concentrated  acid  decomposes  this  alkali 
and  colors  it  blue,  this  being  a  well-marked  test  of  narceia,  and 
by  gently  heating  after  the  acid  is  added  the  alkali  is  dissolved 
and  retained  in  solution,  whilst  when  heated  alone  in  200  parts  of 
water  it  dissolves,  but  on  cooling  nearly  the  whole  crystallizes 
out  in  bulky  acicular  crystals. 
Narceia,  according  to  Couerbe  (Gmelin  Handb.  xvi.,  420),  is 
best  obtained  from  the  black,  dense,  mother  liquor  left  after  crys- 
tallizing out  the  muriates  of  morphia  and  codeia  in  Gregory's 
process  for  morphia.  This  liquor  is  evaporated  to  a  syrupy  con- 
sistence, diluted  with  water,  acidulated  with  HC1,  and  allowed  to 
cool,  when  a  matter  like  ulmin  separates  and  rises  to  the  surface. 
This  is  filtered  and  rendered  alkaline  by  ammonia,  which  preci- 
pitates morphia  and  thebain  as  a  black  precipitate.  The  liquor 
filtered  is  evaporated  to  a  thin  syrup,  and  shaken  repeatedly 
with  ether,  which  renoves  opianyl.  The  remaining  black  liquid, 
on  standing,  solidifies  to  a  crystalline  mass ;  the  crystals,  being 
narceia,  are  washed  with  cold  water,  collected  on  paper,  pressed, 
dried,  and  re-crystallized  from  alcohol. 
NOTE  ON  SOLUTION  OF  CITRATE  OF  MAGNESIA. 
Editor  American  Journal  of  Pharmacy. 
Sir, — From  the  number  of  communications  published  in  the 
Journal  of  Pharmacy  in  regard  to  the  preparation  of  Liquor 
Magnesia?  Citratis,  I  conclude  that  the  following  formula,  given 
to  me  by  a  former  Assistant,  Mr.  Jas.  A.  Criswell,  of  Woodville, 
Miss.,  may  be  of  value  to  some  of  your  readers;  I  have  been 
preparing  it  for  some  time  in  this  way  and  have  never  seen  any 
precipitate,  nor  heard  any  complaint  of  its  effects  from  my  custo- 
