LIQUOR  AMMONIiE  ACETATIS. 
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LIQUOR  AMMONIA  ACETATIS. 
By  Thomas  Byrnes,  M.  D. 
There  is  scarcely  any  preparation  of  the  pharmacopoeia  that 
will  be  found  to  vary  so  much  as  the  liquor  ammonise  acetatis. 
This  variation  arises  from  its  mode  of  preparation,  it  nearly 
always  being  too  alkaline  or  too  acid;  physicians  observe  this, 
and  sometimes  complain  of  it.  I  once  saw  a  prescription  for 
this  remedy,  to  which  was  appended  the  following  caution,  "  be 
sure  and  get  this  mixture  neutral,  as  its  being  alkaline  would 
seriously  injure  the  patient."  I  knew  another  physician  who 
always  required  this  medicine  to  be  brought  to  him  before  he 
would  allow  the  patient  to  use  it. 
Liquor  ammonia  acetatis  is  directed  to  be  made  by  adding 
carbonate  of  ammonia  to  diluted  acetic  acid  until  it  is  saturated. 
But  here  arises  the  difficulty,  for  each  druggist  has  his  own 
favorite  method  of  determining  this  point;  some  tell  best  by  the 
taste,  others  by  its  ceasing  to  effervesce  on  the  addition  of  car- 
bonate of  ammonia.  I  know  of  one  druggist  who  always  de- 
termines the  point  of  saturation  by  listening  to  the  vessel  in 
which  it  is  being  prepared. 
Others  again,  who  are  more  scientific,  rely  upon  test  paper, 
but  all  of  these  means  generally  fail  to  give  a  neutral  solution 
of  the  acetate  of  ammonia. 
Taste  may  indicate  if  the  solution  contains  too  much  of  the 
acid  or  alkali,  but  it  cannot  determine  its  point  of  saturation. 
Adding  ammonia  until  effervescence  ceases  is  very  fallacious, 
as  quite  a  large  quantity  of  free  alkali  may  be  taken  up  before 
effervescence  ceases,  especially  if  the  carbonate  has  been  rapidly 
added. 
Test  paper  it  is  very  certain  cannot  be  relied  upon,  and  un- 
fortunately we  cannot  weigh  out  the  quantities  so  as  to  exactly 
neutralize  each  other,  owing  to  the  variable  strength  of  acetic 
acid,  and  carbonate  of  ammonia,  much  of  the  latter  article  often 
being  a  bicarbonate  as  found  in  the  shops,  especially  if  it  has 
been  long  kept. 
It  is  well  known  that  the  acetates,  though  neutral  in  composi- 
