Am.  Jour.  Pharm.  1 
Aug.,  1875.  i 
Salicylic  Acid. 
343 
that  of  water,  nor  to  camphor,  which  Mr.  R.  Rother  has  proven 
(1871)  to  be  more  soluble  in  cold  than  in  hot  water. 
The  modifications  which  we  would  suggest  for  the  next  revision  of 
the  Pharmacopoeia  are,  that  the  medicated  waters  containing  volatile 
oils  be  prepared  by  distillation  from  the  drugs,  with  a  supplementary 
process  for  the  extemporaneous  preparation  of  some  of  them  from  the 
volatile  oils,  discarding,  however,  the  use  of  carbonate  of  magnesium. 
SALICYLIC  ACID. 
BY  J.  U.  LLOYD. 
Take  of — 
Pure  oil  of  wintergreen,         .        .        .         (3)  three  parts. 
Caustic  potassa,  .....     (2^)  two  and  one-half  parts. 
Muriatic  acid,       .    •    .       .       .        .         (4)  four  parts. 
Distilled  water,  .        .       .       .        .      q.  s. 
Dissolve  the  hydrate  of  potassium  in  an  evaporating-dish  with  one 
and  one-fourth  parts  (ij)  parts  of  water,  heat  to  io8°  F.,  and  stir  in 
the  wintergreen  oil,  continuing  the  agitation  until  the  effervescence 
ceases.  Allow  the  mixture  to  remain  quiet  a  few  moments  until  it 
separates  into  two  layers,  the  lower  of  which  is  impure  solution  of 
salicylate  of  potassium  ;  the  upper,  a  hydrocarbon,  which  is  worthless. 
Then  draw  out  the  solution  of  salicylate  of  potassium  with  a  syphon, 
and  gradually  add  it,  with  constant  stirring,  to  the  muriatic  acid  pre- 
viously diluted  with  ten  parts  of  water.  Allow  the  magma  of  fine 
crystals  to  remain  in  a  cool  place  twenty-four  hours,  then  pour  on  a 
muslin  strainer,  and,  after  draining,  wash  them  well  with  cold  distilled 
water.    Purify  by  dissolving  and  crystallizing. 
Remarks, — Upon  adding  the  wintergreen  oil  to  the  solution  of  hydrate 
of  potassium  the  mixture  at  first  thickens,  but  quickly  liquefies  with 
effervescence,  which  continues  until  the  addition  of  the  oil  is  com- 
pleted. The  reaction  is  accompanied  with  an  increase  of  about  twenty- 
four  degrees  in  temperature.  The  overlaying  oily  liquid  is  colorless, 
while  the  lower  stratum  is  dark,  even  though  a  freshly-distilled  and 
colorless  oil  is  operated  upon. 
Note. — Except  in  the  practical  details  of  the  manipulation,  the 
above  process,  in  its  outlines,  has  been  proposed  by  the  late  Professor 
Wm.  Procter,  Jr.,  in  1854,  in  this  Journal,  pp.  59  and  66. — Editor 
Amer.  Journ.  Pharm. 
