14 
ANTIDOTE  AT  ONCE  FOR  PRUSSIC  ACID,  ETC. 
be  added  till  in  slight  excess  with  certainty,  as  its  odor  detects 
an  excess  instantly,  and  Bunsen  and  others  have  shown  that  a 
slight  excess  of  ammonia  is  advantageous.  In  order  to  render 
the  following  recipes  for  antidotes  intelligible  to  the  American 
pharmaceutist,  we  will  state  that  one  three-fourths  drachms  of  our 
officinal  solution  of  tersulphate  of  iron  is  equal  to  one  drachm  of 
the  solution  of  perchloride  of  the  British  Pharmacopoeia,  used  in 
the  recipes.  We  also  insert  a  supplement  to  the  MM.  Smiths' 
paper,  from  the  "Pharmaceutical  Journal"  for  November,  mo- 
difying the  prussic  acid  test. — Ed.  Am.  J.  Ph.] 
While  engaged  in  these  experiments  on  the  antidotal  action 
of  hydrated  oxide  of  iron  on  the  poisonous  effects  of  arsenic, 
the  remarkable  case  of  Dr.  Pritchard  had  just  occurred ;  and  it 
at  once  occurred  to  us  that  there  was  a  great  likelihood,  princi- 
pally from  the  many  chemical  relations  of  antimony  to  arsenic, 
that  the  hydrated  oxide  of  iron  might  also  be  an  antidote  to  the 
poisonous  action  of  antimony. 
A  few  experiments  soon  confirmed,  in  the  fullest  manner,  our 
anticipations.  A  mixture  of  solution  of  perchloride  of  iron, 
containing  eighty  grains  of  anhydrous  peroxide  of  iron  and  a 
solution  of  one  ounce  avoirdupois  of  crystallized  carbonate  of 
soda,  was  prepared ;  to  this  mixture,  containing  hydrated  per- 
oxide of  iron  and  chloride  of  sodium,  was  added  a  solution  of 
ten  grains  of  tartar  emetic:  the  whole  was  thoroughly  agitated, 
and  thrown  on  a  filter.  The  filtered  liquid,  acidulated  with 
muriatic  acid,  was  tested  with  sulphufetted  hydrogen  for  anti- 
mony, but  not  a  trace  was  f  umd.  The  filter,  with  its  contents, 
was  then  mixed  with  oth^r  teS  grains  of  tartar  emetic,  which 
were  again  removed  by  the  oxid;  of  iron.  A  third  quantity  of 
tartar  emetic  added  was  almost  entirely  removed,  so  that  eighty 
grains  of  hydrated  peroxide  absorb  nearly  thirty  grains 
1  AC 
of  tartar  emetic  from  solution. 
The  absorbing  action  of  hydrated  oxide  of  iron  Awards  anti- 
mony  would  be  still  more  striking  but  for  the  dissolving  power 
of  the  tartaric  acid,  set  free,  upon  the  peroxide  of  iron.  That 
the  oxide  of  iron  does  not  merely  act  by  taking  the  organic  acid 
and  precipitating  the  oxide  of  antimony  in  an  insoluble  state,  is 
0 
