448 
Bromide  of  Quinia,  etc. 
J  Am.  Jour.  Ph arm. 
\     Oct.  1,1872. 
■drobromic  acid  with  freshly  precipitated  carbonate  of  baryta.  The 
following  is  a  good  method  : 
Put  1  oz.  by  weight  of  bromine  and  8  fluidounces  of  water  into  a 
pint  jar.  Attach  a  sulphuretted  hydrogen  apparatus,  being  careful 
to  so  place  the  end  of  the  delivery  tube  that  it  will  touch  the  surface 
of  the  bromine,  and  pass  a  stream  of  sulphuretted  hydrogen  slowly 
through  until  the  bromine  is  entirely  converted  into  hydrobromic  acid. 
Filter  the  hydrobromic  acid  solution  into  a  capsule,  and  warm  gently 
until  it  has  lost  all  sulphurous  odor. 
To  make  the  carbonate  of  baryta,  to  a  boiling  solution  of  2  oz.  of 
chloride  of  barium  in  a  pint  of  water,  add  solution  of  carbonate  of 
ammonia  (to  which  a  little  ammonia  has  been  added)  in  excess,  wash  the 
precipitate  three  or  four  times  by  decantation,  and  afterwards  trans- 
fer it  to  a  filter,  and  continue  the  washing  until  the  filtrate  ceases  to 
produce  any  turbidity  on  the  addition  of  a  solution  of  nitrate  of  silver, 
to  which  a  few  drops  of  nitric  acid  have  been  added.  Then  remove 
the  precipitate  from  the  filter,  and  mix  it  with  sufficient  water  to 
bring  it  to  the  consistence  of  thick  milk. 
To  make  the  bromide  of  barium,  add  to  the  hydrobromic  acid  solution 
small  portions  at  a  time  of  the  mixture  of  carbonate  of  baryta  and  water, 
until  rather  more  than  three-fourths  of  the  mixture  has  been  added. 
When  this  quantity  has  been  added,  apply  a  gentle  heat  and  shake 
vigorously.  Then  filter  a  small  portion  and  test  with  litmus  paper. 
If  it  shows  an  acid  reaction,  more  carbonate  of  baryta  must  be  added 
until  the  reaction  is  neutral.  When  a  sufficient  quantity  of  carbonate 
of  baryta  has  been  added,  filter  and  evaporate  to  4  fluidounces.  It  is 
not  necessary  to  proceed  to  crystallization,  as  the  salt  is  very  soluble, 
and  therefore  difficult  to  crystallize  in  small  quantities,  and  a  solution 
of  it  is  really  what  is  wanted  after  all. 
Bromide  of  Quinia. — To  make  this  salt,  dissolve  1  oz.  of  medicinal 
sulphate  of  quinia  in  32  fluidounces  of  boiling  water,  and  add  solution 
of  bromide  of  barium  until  a  precipitate  ceases  to  be  produced.  (A 
little  less  than  5  fluidrachms  of  the  solution  of  bromide  of  barium 
made  by  the  formula  given  above,  will  be  about  the  proper  quantity.) 
Filter  a  small  quantity  of  the  solution,  acidulate  it  slightly  with  nitric 
acid,  and  test  for  baryta  with  a  few  drops  of  diluted  sulphuric  acid. 
If  a  whitish  turbidity  is  produced,  it  is  an  indication  that  too  much 
bromide  of  barium  has  been  added,  and  enough  sulphate  of  quinia 
must  be  added  to  entirely  decompose  it.    If,  on  the  other  hand,  the 
