564 
Hydrobromate  of  Quinia. 
f  Am.  Jour.  Pharm. 
\    Dec.  1, 1874. 
are  distilled  to  recover  the  alcohol,  afterwards  filtered,  to  separate 
the  sulphate  of  quinia  which  has  been  precipitated  by  the  water,  and 
then  concentrated  sufficiently  to  induce  rapid  crystallization.  The 
addition  of  water  is  indispensable  for  the  concentration  and  crystal- 
lization ;  the  hydrobromate,  being  soluble  in  alcohol  in  all  propor- 
tions, redissolves  as  the  alcoholic  liquor  is  concentrated. 
Neutral  hydrobromate  of  quinia  is  also  obtained  easily  by  dissolv- 
ing hydrate  of  quinia  in  weak  hydrobromic  acid.  Upon  cooling  the 
salt  forms  beautiful  nacreous  crystals  ;  redissolved  several  times  in 
water,  it  crystallizes  in  the  basic  state. 
Neutral  hydrobromate  of  quinia  has  for  its  formula: 
C20H24N2O2,HBr,H2O. 
Experiment.  Theory. 
Water,  .        .       .         4-80      .        .       .  4-25 
Bromine,       .       .       18-26      .       .       .  18-91 
Quinia,         .       .       75-20      .       .       .  76*59 
The  formula  for  acid  hydrobromate  of  quinia  is  : 
C20H24N2O2,2(HBr),3H2O. 
Theory.  Experiment. 
Water,  .       .       .       10-00      .       .  .  10-00 
Bromine,       .       .       24-62      .       .  ,  28-84 
Quinia,         .       .       60-00      .       .  .  50-60 
The  crystallization  of  the  acid  hydrobromate  of  quinia  in  well- 
defined  regular  facets  distinguishes  it  from  the  hydrochlorates, 
which  crystallize  silky  in  filaments.  The  former  crystals  do  not 
become  resinous  in  the  presence  of  an  excess  of  hydrobromic  acid, 
and  are  prepared  by  dissolving  quinia  in  an  excess  of  hydrobromic 
acid  ;  they  are  soluble  in  water  and  alcohol. 
The  solubility  of  neutral  hydrobromate  of  quinia  is  stated  by  the 
author  to  be  very  remarkable,  it  being  soluble  in  five  times  its  weight 
of  water.  This  solubility  of  the  neutral  salt  he  considers  to  be  a 
property  of  high  therapeutic  value,  as  it  should  be  better  tolerated 
than  the  neutral  sulphate,  and  more  active,  being  more  quickly  ab- 
sorbed. More  soluble  and  more  rich  in  quinia  than  the  acid  sul- 
phate, he  thinks  it  might  replace  the  latter  advantageously  in  various 
liquid  preparations,  without  causing  the  least  irritation  of  the  mucous 
membrane.  Further,  it  combines  the  properties  of  bromine  and  the 
salts  of  quinia,  whilst  its  easy  absorption  allows  of  its  internal  admin- 
