22  Changes  in  Formulas  of  Galenicals.  {AfaJ^y  ^jV7m' 
In  the  Tinctures,  several  changes  are  of  special  interest.  In  Tinc- 
ture of  Arnica,  in  order  to  insure  the  exhaustion  of  the  drug,  inter- 
rupted percolation  is  directed. 
In  Tincture  of  Cantharides,  a  process  of  maceration  with  warm 
alcohol  is  directed.  The  cantharides  directed  (10  per  cent.)  can 
never  be  fully  extracted  by  the  alcohol  and  all  we  can  succeed  in 
doing  is  to  make  a  saturated  alcoholic  solution  of  the  active  con- 
stituent, and  this  is  attained  by  macerating  at  a  temperature  of  50 
to  55°  C. 
In  Compound  Tincture  of  Gentian,  the  addition  of  glycerin  and 
the  reduction  of  the  alcoholic  strength  to  that  of  diluted  alcohol  is 
to  be  noted. 
In  Tincture  of  Iodine,  in  order  to  insure  the  solution  of  the 
iodine,  50  mils  of  water  per  liter  is  added. 
Tincture  of  Kino  of  the  U.  S.  P.  VIII  was  not  a  satisfactory 
preparation.  The  addition  of  glycerin  and  the  attempt  at  filtration 
meant  a  long  exposure  with  associated  contamination  which  engen- 
dered enzymic  action  and  the  early  gelatinization  of  the  product. 
The  U.  S.  P.  IX  directs  the  extraction  of  the  kino  in  a  flask  with 
boiling  water,  the  alcohol  being  added  to  the  cooled  decoction  and 
the  tincture  decanted  and  strained.  By  this  simplified  process,  ex- 
posure of  the  kino  is  avoided  and  a  more  permanent  preparation  is 
secured. 
Tincture  of  Nux  Vomica  is  now  directed  to  be  made  directly 
from  the  powdered  drug  by  percolation  with  the  menstruum  and 
then  assayed,  the  standard  being  fixed  at  total  alkaloids  .25  Gm.  in 
100  mils  instead  of  strychnine  0.1  Gm. 
In  Tincture  of  Sanguinaria,  hydrochloric  acid  is  directed  in 
place  of  acetic  acid,  with  the  alcoholic  strength  of  the  menstruum 
remaining  the  same  as  in  the  previous  revision.  One  has  but  to  try 
the  use  of  hydrochloric  acid  in  the  extraction  of  sanguinaria  to  note 
its  value  for  this  purpose. 
In  the  Tincture  of  Strophanthus,  we  note  a  decided  improvement 
over  the  formula  of  the  U.  S.  P.  VIII.  Strophanthus  is  a  drug 
that  is  very  difficult  to  extract  and  its  large  percentage  of  disagree- 
able fat  is  another  troublesome  factor.  The  U.  S.  P.  VIII  directed 
that  the  tincture  be  made  with  a  menstruum  consisting  of  65  volumes 
of  alcohol  and  35  volumes  of  water  without  previously  de-fatting 
the  drug.  The  resulting  tincture  was  cloudy  from  separated  oil  and 
was  exceedingly  nauseating  because  of  the  presence  of  the  fat. 
