CHALK  MIXTURE. — TINCT.  CINCH.    COMP.  393 
tact  with  vapors  from  muriatic  acid,  and  the  white  cloud-like 
appearance  was  formed.  The  vapor  also  restored  litmus  paper 
to  its  blue  color,  after  being  reddened  by  nitric  acid.  This 
proved  at  once  that  the  alkalinity  of  the  nux  vomica  was  due  to 
ammonia,  and  not  to  strychnia,  as  I  thought.  But  the  crystals 
formed  in  the  bottle  were  strychnia  with  a  small  amount  of 
brucia,  as  I  have  stated  before,  and  no  doubt  were  displaced  by 
the  ammonia.        Yours  respectfully, 
Geo.  W.  Kennedy. 
Pottsville,  July  18,  1870. 
ON  CHALK  MIXTURE. 
By  W.  Ranstead  Jones. 
Editor  Amer.  Journ.  Pharmacy: 
Bear  Sir, — On  several  occasions  I  have  found  chalk  mixture, 
prepared  as  directed  by  the  U.  S.  D.,  to  turn  sour,  if  made  for 
a  few  days.    To  avoid  this  I  have  pursued  the  following  plan 
with  satisfaction.    I  prepare  a  powder  of 
Prepared  Chalk,  ^ss. 
P.  Sacch.  Alb., 
P.  G.  Acacia,  aa  5ij. 
Mix  well  by  rubbing  in  a  mortar,  and  keep  well  stopped  from 
the  air  in  a  bottle.    Where  the  chalk  mixture  is  required,  take 
3j  of  the  powder  to  f^ss  each  of  water  and  cinnamon  water  for 
each  fg  of  chalk  mixture  required. 
Mt.  Airy,  Fhila.,  Aug.  11,  1870. 
TINCTURA  CINCHONA  COMPOSITA. 
To  the  Editor : 
As  the  time  is  fast  drawing  near  when  our  Pharmacopoeia 
will  be  revised,  I  thought  it  would  not  be  out  of  place  to  make 
a  suggestion  in  reference  to  the  U.  S.  P.  formula  for  Tinct. 
Cinch.  Comp.  The  composition  of  it,  as  we  are  all  aware,  is  red 
cinchona  bark,  bitter  orange  peel,  Virg.  snake  root,  saffron  and 
red  Saunders.  What  I  want  to  call  attention  to  is  the  red  saun- 
ders.  Why  is  it  used  in  the  preparation  for  no  other  purpose 
than  to  give  the  tincture  a  dark  red  color  ?    Now  we  have  color- 
