Am.  Jour.  Pharm.  | 
May,  1911.  / 
Identification  of  Cocaine, 
197 
tion  of  this  2  per  cent,  solution,  say  ^  c.c,  is  set  aside  for  the 
permanganate  test.  The  remaining  solution  is  diluted  with  an 
equal  volume  of  water,  forming  a  i  per  cent,  solution.  Portions 
of  y2  c.c.  of  this  solution  are  reserved  for  the  platinum  chloride 
and  chromic  acid  tests.  To  a  third  ^  c.c.  portion  of  the  i  per 
cent,  solution  is  added  i  c.c.  water  and  the  resulting  liquid  used 
for  the  gold  chloride  test. 
Fig.  2. 
Cocaine-chloro-aurate,  x  loo. 
POTASSIUM  PERMANGANATE  TEST.'' 
To  ^2  C.C.  of  a  2  per  cent,  solution  of  cocaine  are  added  five 
drops  of  permanganate  test  solution.  A  precipitate  is  formed  con- 
sisting of  violet-red,  rectangular  plates.  The  other  common  alka- 
loids either  immediately  or  slowly  reduce  the  permanganate  without 
forming  crystalline  precipitates.^  This  is  also  true  of  the  cocaine 
substitutes,  holocaine,  acoine,  and  euphthalmine,  which  almost  in- 
^  F.  Giesel,  Pharm.  Zeit.,  1886,  p.  132. 
'Allen,  Comm.  Org.  Anal.  2d  Ed.,  vol.  iii,  pt.  ii,  p.  144. 
