A  octobeJ,"  1915™' }     Examination  of  Opium  Alkaloids.  461 
If  0.1  Gm.  of  papaverine  hydrochloride  be  dissolved  in  10  Cc.  of 
water  and  a  few  drops  of  hydrochloric  acid  added,  the  solution 
should  not  at  once  become  turbid  on  the  addition  of  a  few  drops  of 
barium  chloride  solution  (limit  of  sulphates). 
If  from  0.2  to  0.3  Gm.  of  papaverine  hydrochloride  be  weighed 
and  the  salt  burned,  the  ash  should  not  exceed  0.1  per  cent,  of  the 
weight  taken. 
If  from  0.2  to  0.3  Gm.  of  papaverine  hydrochloride  be  weighed, 
dissolved  in  20  Cc.  of  warm  water,  the  solution  cooled,  a  slight  ex- 
cess of  ammonia  water  added,  and  the  mixture  shaken  with  three 
successive  portions  of  25  Cc.  each  of  ether,  or  a  sufficient  quantity 
to  complete  the  extraction,  the  ether  solutions  combined,  washed 
with  water,  evaporated  to  dryness,  the  residue  dried  to  constant 
weight  at  ioo°  C.  and  weighed,  the  weight  should  indicate  not  less 
than  88  per  cent,  of  papaverine.  The  alkaloid  obtained  by  this  pro- 
cess should  melt  between  146.5 0  and  147.5 0  C- 
If  from  0.2  to  0.3  Gm.  of  papaverine  hydrochloride  be  weighed, 
dissolved  in  20  Cc.  of  warm  water,  the  solution  cooled,  a  few  drops 
of  diluted  hydrochloric  acid  added,  1  Cc.  of  freshly-prepared  potas- 
sium ferricyanide  solution  added,  the  mixture  agitated,  allowed  to 
stand  over  night,  filtered,  the  filtrate  made  alkaline  with  ammonia 
water,  shaken  with  several  successive  portions  of  ether,  the  ether  solu- 
tions combined  wasted  with  water,  evaporated,  the  residue  dried  at 
ioo°  C.  and  weighed,  the  weight  should  not  amount  to  more  than 
2  per  cent,  of  the  weight  taken  (limit  of  the  salts  of  foreign  opium 
alkaloids) . 
Monograph  V. 
THEBAINE  HYDROCHLORIDE  (C19H21OgN  .  HQ  .  H20). 
The  hydrochloride  of  the  alkaloid,  thebaine,  containing  not  less 
than  84.5  per  cent,  of  thebaine. 
Thebaine  hydrochloride  occurs  in  colorless,  or  very  faintly  yel: 
lowish,  rhombic  prisms ;  odorless ;  taste  acrid  and  styptic ;  permanent 
in  the  air. 
Thebaine  hydrochloride  is  soluble  in  water ;  soluble  in  alcohol ; 
very  soluble  in  chloroform ;  insoluble  in  ether. 
At  no°  C.  thebaine  hydrochloride  loses  its  water  of  hydration 
(4.9  per  cent.)  with  slight  decomposition.  At  ioo°  C.  in  a  vacuum 
the  salt  becomes  anhydrous  without  decomposition.  If  exposed  to 
the  air  the  anhydrous  salt  absorbs  water  equivalent  to  one  molecule 
of  water  of  hydration. 
An  aqueous  solution  of  thebaine  hydrochloride  is  neutral  to  lit- 
