246  Iodide  and  Bromide  of  Potassium.     { A»JuiTi,  f8H7r  • 
Take  of  citrate  of  bismuth,  ammonio-citrate  of  iron,  each  320  grs.; 
water  of  ammonia,  water,  each  a  sufficient  quantity. 
With  4  oz.  of  water  rub  the  citrate  of  bismuth  into  a  smooth  paste ; 
gradually  add  water  of  ammonia  until  solution  has  taken  place,  being 
very  careful  not  to  have  an  excess  of  ammonia.  Now  add  the  ammo- 
nio-citrate of  iron  and  some  more  water  ;  dissolve,  filter,  and  wash 
the  filter  with  enough  water  to  make  the  solution  measure  1  pint. 
This  solution,  if  intended  to  be  long  kept,  may  be  partly  made  up 
with  glycerin,  although  I  cannot  speak  from  experience  whether  it  is 
so  well  borne  by  the  stomach.  A  more  useful  addition,  however,  is 
good  sherry  wine,  of  which  there  may  be  used  10  fl.  oz.  (or  perhaps 
more),  in  place  of  so  much  water. 
The  above  solution  is  prescribed  under  the  name  of  Liquor  Ferri 
et  Bismuthi  Citratis,  and  contains  in  1  fluid-drachm  2|  grains  each  of 
citrate  of  bismuth  and  ammonio-citrate  of  iron.  The  dose  is  from  1 
to  2  fluid-drachms,  half  an  hour  before  meals,  or — when  required — 
after  meals. 
It  is,  of  course,  no  true  double  salt,  chemically  speaking,  but  only 
a  mixture  of  ammonio-citrate  of  bismuth  and  ammonio  citrate  of  iron  ; 
and,  although  a  true  double  salt  containing  those  elements  might 
perhaps  be  prepared,  I  doubt  whether  it  could  have  any  better  effects. 
The  solution  may  also  be  prepared  of  a  concentrated  state,  and 
spread  upon  plates  of  glass  to  dry,  yielding  exceedingly  handsome 
scales  of  a  golden-brown  color,  which  must  be  protected  from  the 
light,  and  5  grains  of  which  are  equal  to  1  fluid- drachm  of  the 
solution. 
New  York,  May  5th,  1872. 
IODIDE  AND  BROMIDE  OF  POTASSIUM. 
By  Chas.  D.  Chase. 
The  object  of  this  note,  as  will  be  seen,  is  simply  to  call  the  atten- 
tion of  dispensers  to  the  fact  that  most  of  the  iodide  and  bromide  of 
potassium  found  in  the  market,  instead  of  being  neutral,  are  alkaline 
in  their  reactions,  and  to  illustrate  the  importance  of  this  fact  being 
generally  known,  the  following  is  given. 
The  following  prescription  was  prepared,  with  results  as  given 
below : 
