MANUFACTURE  OF  PERCHLORIC  ACID. 
19 
which  the  alkaloids  are  previously  dissolved,  a  little  peppermint, 
and  capsicum, — and  perhaps  some  cannabis  indica. 
The  following  recipe  will  furnish  a  preparation  having  the 
pharmaceutical  properties  of  chlorodyne,  according  to  Dr.  Og- 
den  : 
B 
Muriate  of  morphia,  grs.  viii. 
Water,  fl.  3ss. 
Perchloric  acid  (25°  B.)        gtt.  xx. 
Chloroform,  fl.  3jss. 
Tinct.  of  Indian  hemp,         fl.  3j. 
Hydrocyanic  acid  (U.S. P.)   gtt.  xii. 
Molasses,  fl.  3ss. 
Oil  of  peppermint,  gtt.  ij. 
Oleoresin  of  capsicum,  gtt.  i. 
To  the  morphia  and  water  in  a  small  flask  add  the  perchloric 
acid,  and  heat  until  a  clear  solution  is  obtained.  Then  add  the 
molasses,  previously  warmed  to  render  it  fluid.  Heat  the  mix- 
ture, and  agitate  well.  When  cold,  add  the  other  ingredients, 
and  mix  thoroughly. 
MANUFACTURE  OF  PERCHLORIC  ACID. 
By  Charles  Bullock. 
Having  occasion  to  prepare  perchloric  acid  in  some  quantity, 
the  process  of  M.  Deville  for  obtaining  fluosilicic  acid  was  tried 
as  a  preliminary  step. 
The  process  of  M.  Deville  consists  in  passing  steam  through 
a  mixture  of  fluorspar  and  silica  heated  to  redness.  The  water 
is  decomposed  with  the  production  of  hydrofluoric  acid,  which 
takes  up  silica,  and  fluosilicic  acid  distills  over. 
In  the  first  experiment,  an  iron  retort  was  used,  and  in  place 
of  passing  steam  through  the  mixed  ingredients,  water  was  al- 
lowed to  drop  slowly  on  the  hot  materials  through  a  safety  tube. 
A  small  amount  of  weak  acid  was  obtained,  after  which  water 
distilled  over.  In  the  second  experiment,  the  tube  for  intro- 
ducing water  was  carried  to  the  bottom  of  an  iron  retort.  After 
a  small  amount  of  very  weak  acid  had  distilled  over,  the  distil- 
lation ceased.    An  examination  of  the  retort  showed  that  the 
