502  Test  for  Alkaloids  of  Cinchona.      { Member PmT' 
chloric  acid,  while  a  sample  labeled  U.  S.  P.  tested  2.02  per  cent, 
free  acid. 
It  must  be  noted  that  the  presence  of  any  alkali  chlorides  or  other 
chlorides  in  this  solution  would  exclude  the  use  of  this  method,  but 
these  impurities  are  not  apt  to  be  present. 
The  writer  suggests  that  a  test  for  the  amount  of  free  hydro- 
chloric acid  in  Solution  Ferric  Chloride  be  included  in  the  next 
revision  of  the  United  States  Pharmacopoeia. 
Scientific  Department,  Parke,  Davis  &  Co., 
Detroit,  Mich.,  March  6th,  191 3. 
A  NEW  TEST  FOR  THE  ALKALOIDS  OF  CINCHONA. 
By  G.  N.  Watson, 
Drug  Laboratory,  University  of  Kansas. 
An  aqueous  solution  of  Quinine  Sulphate,  when  treated  with  a 
few  drops  of  a  freshly  prepared  saturated  alcoholic  solution  of  Alpha- 
naphthol,  to  which  a  few  drops  of  concentrated  H2S04  have  been 
added  (2  drops  per  1  c.c.)  produces  a  yellow  precipitate.  When  the 
reagent  is  added  in  excess,  a  yellow  solution  is  produced. 
Quinidine,  Cinchonine  and  Cinchonidine  sulphates,  or  a  solution 
of  their  respective  alkaloids  in  dilute  H2S04,  produce  the  same  color 
with  the  Alphanaphthol  reagent.  So  far  as  the  investigation  has  been 
carried,  no  other  white  alkaloids  will  give  the  yellow  color. 
By  means  of  this  reagent  the  alkaloids  of  Cinchona  have  been 
detected  in  the  presence  of  several  alkaloids,  namely,  Atropine,  Mor- 
phine, Cocaine,  Strychnine,  Caffeine,  Brucine,  Codeine  and  Anti- 
pyrine. 
One  c.c.  of  a  solution  of  Quinine  Sulphate  (1-2000)  was  found 
to  produce,  with  the  Alphanaphthol  reagent,  the  characteristic  yellow 
color. 
A  drop  of  the  reagent,  added  to  the  chloroform  or  ether  residues 
of  any  of  the  above  cinchona  alkaloids  produces  an  intensely  yellow 
color. 
