52 
ON  PREPARATIONS  OF  CINCHONA. 
The  success  which  attended  this  experiment  naturally  suggests 
the  use  of  glycerin  in  the  preparation  of  other  apothemic  ex- 
tracts, more  especially  the  astringent  ones  ;  (no  doubt  it  would 
be  useful  in  the  preparation  of  fluid  extract  of  rhubarb ;)  and 
it  is  believed  that  in  the  hands  of  future  experimenters  it  will  be 
found  a  most  useful  solvent  in  such  preparations. 
It  was  thought  that  the  addition  of  acids,  or  perhaps  of  al- 
kalies in  small  quantity,  to  the  menstruum  might  render  the 
tincture  of  cinchona  a  permanent  solution,  notwithstanding  the 
fact  that  the  character  of  the  resulting  preparation  would  be  some- 
what modified  thereby.  The  addition  of  ammonia  or  potassa  to  the 
tincture  of  cinchona  deepened  its  color,  and  by  dissolving  the  cin- 
chonic  red,  permanently  prevented  its  deposition.  Upon  standing, 
however,  minute  crystals  of  cinchonia  or  quinia,  or  perhaps 
both,  were  deposited  upon  the  sides  and  bottom  of  the  bottle 
containing  the  tincture,  and  consequently  the  preparation  was 
more  injured  than  it  would  have  been  by  the  deposition  of  the 
cinchonic  red,  if  the  alkali  had  not  been  added. 
The  addition  of  an  acid  to  the  tincture  of  cinchona  seems  to 
render  the  solution  almost,  if  not  entirely,  permanent;  and, 
although  in  this  experiment,  as  in  the  preceding  one,  the  natural 
combination  of  the  constituents  of  cinchona  bark  is  not  pre- 
served, it  is  believed  that  an  acidulated  tincture  of  cinchona 
would,  in  very  many  cases,  prove  a  valuable  and  desirable  pre- 
paration. 
The  following  formula  is  suggested  for  this  preparation : 
Acidulated  Tincture  of  Cinchona. 
Take  of  Yellow  Cinchona,  in  moderately  fine  powder,  six 
troyounces. 
Aromatic  Sulphuric  Acid  half  a  fluidounce. 
Diluted  Alcohol  a  sufficient  quantity. 
Having  mixed  the  acid  with  a  pint  of  diluted  alcohol,  moist- 
en the  powder  with  two  fluidounces  of  the  mixture,  pack  it 
firmly  in  a  glass  percolator,  and  pour  upon  it,  first  the  re- 
mainder of  the  mixture,  and  afterwards  sufficient  diluted  alco- 
hol to  make  the  tincture  measure  two  pints. — Proc.  Amer. 
Pharm.  Assoc.,  1864. 
