^ovembexX'}     Alkaloids  and  Alkaloidal  Drugs.  523 
Three  assays  of  a  sample  of  opium,  which  by  the  method  of  the 
U.S.P.,  1890,  was  found  to  contain  14  per  cent,  of  morphine,  were 
carried  out  by  the  method  described  in  the  accompanying  paper. 
Both  the  alkalimetric  and  iodometric  methods,  agreeing  quite  well 
with  each  other,  gave  results  considerably  above  those  obtained  by 
the  U.S.P.  method. 
N 
Opium           20  Acid  Con"  Grammes  of  Iodine  Per  Cent.  Morphine 
Taken  in         sumed  by  2-5  Consumed  by  ^  Found. 
Grammes.     Grammes  Opium.  Gramme  Opium.  Alkalimetric.  Iodometric. 
i'3  31*1  0-116652  17-66  17*50 
2-3  31-5  0-116672  17-90  17-50 
3*3  3**3  0-116590  17-78  17-49 
HOT  EXTRACTION  INSTEAD  OF  COLD  PERCOLATION    IN    THE   ASSAY  OF 
OPIUM.1 
Instead  of  extracting  the  morphine  from  the  opium  by  cold  per- 
colation with  an  alcohol-chloroform  mixture  as  here  described,  hot 
extraction  with  chloroform  alone  in  a  suitable  extraction  apparatus 
may  be  used.  Though  morphine  is  very  slightly  soluble  in  cold 
chloroform,  it  dissolves  much  more  easily  on  the  application  of  heat. 
This  has  been  shown  by  Florio.2  and  verified  by  us.  The  most 
suitable  apparatus  for  this  case  is  undoubtedly  that  of  Dunstan  and 
Short,3  as  it  can  be  used  for  cold  percolation  as  well  as  for  hot  ex- 
traction. If  this  method  of  extraction  be  preferred,  the  opium 
mixed  with  the  sodium  chloride  is  placed  in  this  apparatus  and  ex- 
hausted by  cold  percolation  with  benzol,  as  described  above.  A 
current  of  dry  air  is  then  passed  through  the  tube  till  the  powder 
becomes  dry,  which  can  be  seen  by  the  light  color  that  the  powder 
assumes,  or  by  the  fact  that  the  tube  ceases  to  feel  colder  than  the 
surrounding  medium,  the  apparatus  then  connected  with  a  small 
round-bottomed  flask  containing  40  to  50  c.c.  of  chloroform,  and 
the  powder  extracted  on  a  water-bath  till  exhaustion  is  complete. 
Care  should  be  taken  that  only  a  small  surface  of  the  bottom  of  the 
flask  be  heated,  and  that  a  layer  of  solvent  be  constantly  on  top  of 
the  powder.    Most  of  the  chloroform  can  then  be  distilled  off  and 
1See  the  section  on  the  hot  extraction  method  as  an  alternative  to  cold  per- 
colation, in  the  general  process  for  analytical  extraction  of  drugs  in  "  Direc- 
tions for  Certain  Alkaloidal  Assays."    (Amer.  Jour.  Pharm.,  1899,  p.  462.) 
2  Gaz.  chim.  Ital.,  13,  496. 
3  Pharm.  Jour.  (3),,  xiii,  664. 
