Am.  Jour.  Pharm. ) 
March,  1885.  ) 
Tincture  of  Feme  Chloride. 
117 
the  hydrogen  of  the  decomposed  water,  while  the  freed  oxygen  atoms 
of  tlie  latter  unite  with  those  of  the  altered  anhydride  to  nitrous  anhy- 
dride (N2O3),  which,  through  its  strong  affinity  for  moisture,  quickly 
absorbs  one  molecule  of  water  to  form  the  more  stable  nitrous  acid 
(HNO2).  . 
If,  according  to  the  Pharmacopoeia,^  1  part  of  nitric  acid  requires 
3f  parts  of  hydrochloric  acid  for  mutual  decomposition  in  making 
nitrohydrochloric  acid,  it  is  evident  that  the  excess  of  6  parts  of  HCl 
present  in  the  liquor  is  only  partially  changed  by  the  excess  of  1  part 
of  HNO3,  and  the  remaining  2J  parts  of  hydrochloric  acid  must 
remain  free  and  unchanged,  because  of  the  insufficiency  of  free  nitric 
acid. 
Now,  in  the  simple  decomposition  of  the  two  acids  previously  men- 
tioned we  have  a  ready  solution  for  the  main  cause  of  the  production 
of  ethyl  nitrite,  since  it  is  well  known  that  nitrous  acid,  or  even 
nitrous  anhydride,  when  brought  in  contact  with  alcohol,  readily  gene- 
rates that  ether. 
The  claim  that  the  liquor  forms  nitrohydrochloric  acid  needs  no 
labored  argument  to  prove,  since  the  presence  of  free  nitrous  acid  in 
the  commercial  liquid  has  been  determined  in  a  number  of  samples  by 
the  author  in  following  the  modified  test  for  nitrous  acid  previously 
mentioned.  The  occasional  presence  of  traces  of  free  chlorine  has 
also  been  observed  through  the  ready  solubility  of  gold  leaf  in  the 
liquid.  In  regard  to  the  free  chlorine,  however,  it  is  fair  to  assume 
that  it  is  almost  entirely  dissipated  on  the  application  of  heat. 
Mr.  Rother  has  constructed  a  formula  for  the  "  Liquor,"  founded  upon 
the  oxidizing  properties  of  chloric  acid,  resulting  from  the  decompo- 
sition of  barium  chlorate  with  acid,  upon  ferrous  chloride  in  acid  solu- 
tion, the  barium  being  precipitated  with  sulphuric  acid. 
As  a  general  rule,  the  reception  and  permanency  of  any  new  phar- 
maceutical process  is,  in  the  main,  dependent  upon  its  simplicity  of 
structure  and  its  freedom  or  non-liability  of  contaminating  impurities 
arising  from  defective  modes  of  procedure.  There  is  no  doubt  that, 
under  exact  conditions  and  in  careful  hands,  this  process  would  give 
good  results ;  but  if,  in  the  making  of  this  product,  there  is  danger, 
either  from  the  explosive  character  of  the  chloric  acid  formed,  or  the 
liability  to  retain  a  poisonous  impurity  in  the  form  of  a  soluble,  unpre- 
^U.  8.  P.,  Acidum  Nitrobydrocbloricum,  p.  18. 
