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BICARBONATE  OF  AMMONIA. 
ON  BICARBONATE  OF  AMMONIA  AS  A  PHARMACEUTICAL 
PREPARATION. 
By  William  Procter,  Jr. 
The  writer  for  many  years  past  has  used  this  salt  as  an  antacid 
in  place  of  bicarbonate  of  soda,  and  now  brings  it  forward  as 
deserving  the  attention  of  physicians  in  certain  gastric  affections 
wherein  its  antacid  and  substimulating  powers  may  be  indicated, 
m  connection  with  bitter  tonics,  aperients  and  aromatics. 
It  is  well  known  to  druggists  that  considerable  quantities  of 
this  salt  are  formed  on  the  sides  of  casks  in  which  carbonate  of 
ammonia  is  imported ;  and  other  portions  are  derived  from  the  acci- 
dental or  careless  exposure  of  the  sesqui-carbonate,  whereby  an 
equivalent  of  mono-carbonate  is  lost.  Even  in  the  shop  bottles 
of  dispensers  this  is  constantly  going  on  to  a  limited  extent.  It 
has  been  usual  to  reserve  the  salt  thus  obtained  for  forming 
acetate,  nitrate,  or  other  ammoniacal  salts,  but  it  has  rarely  been 
used  medicinally  on  its  own  m.erit.  If  it  were  sufficiently  abun- 
dant, or  could  be  prepared  cheaply  by  a  direct  process,  it  would 
form,  by  all  odds,  the  best  yeast  powder  that  can  be  offered,  as  it 
contains  a  larger  portion  of  carbonic  acid  than  any  of  the  alkaline 
bicarbonates,  except  that  of  lithia,  which  of  course  is  unsuited  to 
this  use,  but  it  is  too  scarce  for  that  use  now.  Bicarbonate  of 
ammonia  in  its  purest  state  is  a  white  salt,  isomorphous  with  bi- 
carbonate of  potassa,  and  possesses  the  same  crystalline  form. 
Its  composition  is  NH4,0-]-2C02,  HO.  Its  taste  is  saline  with 
a  slightly  ammoniacal  impression,  and  is  slowly  volatile  when 
exposed,  and  gradually  evaporates  with  a  slight  odor  of  ammo- 
nia. It  is  soluble  in  8  parts  of  water  at  60°F,  and  its  aqueous 
solution  has  an  alkaline  reaction  with  syrup  of  violets,  (Liebig.) 
It  is  decomposed  by  the  heat  of  boiling  water,  giving  off 
carbonic  acid ;  on  this  property  its  merit  as  an  yeast  powder 
partially  depends.  It  is  nearly  insoluble  in  officinal  alcohol,  but 
soluble  in  parts  of  diluted  alcohol.  It  is  most  easily  pre- 
pared in  a  small  way  by  dissolving  out  the  mono-carbonate  from 
the  powdered  sublimed  sesqui-carbonate  (which  consists  of  one 
equivalent  of  each  salt)  by  aid  of  alcohol  (U.  S.  P.  85  per  cent.) 
in  which  the  bicarbonate  is  but  slightly  soluble.    The  residue 
