Am.  Jour.  Pbarm.) 
March,  1899.  J 
Assay  of  Belladonna  Leaves. 
107 
immediately  with  successive  portions  of  50,  30  and  20  grammes 
solvent  (=  3  parts  chloroform  and  2  parts  ether  by  weight).  The 
combined  ethereal  extractions  are  set  aside  for  a  short  time,  and 
then  passed  through  a  small  filter  moistened  with  ether  into  a  tared 
flask  of  150  to  200  c.c.  capacity,  and  the  solvent  distilled  off.  The 
residue  is  treated  with  2  or  3  small  portions  of  ether,  the  latter 
removed  by  heating  the  flask  in  a  water-bath  ;  the  vapors  of  ether 
are  finally  removed  from  the  flask  by  means  of  a  current  of  air  from 
a  bellows,  and  the  flask  and  contents  heated  in  the  water-bath  for 
periods  of  fifteen  minutes  each,  and  weighed  in  the  intervals  until 
constant  weight  is  obtained.  The  alkaloids  are  dissolved  in  5  to  10 
c.c.  of  neutral,  absolute  alcohol,  water  added  to  the  beginning  of  a 
turbidity  and  the  alkaloids  titrated  with  —  or  J1  hydrochloric  acid, 
10  20 
using  hematoxylin  as  indicator  (3  drops  of  a  1  per  cent,  alcoholic 
solution). 
As  the  result  of  some  preliminary  assays,  several  modifications 
of  this  process  were  made:  (1)  Moisture  was  determined  in  a  sepa- 
rate portion  of  2  grammes  at  1 00°  C,  and  the  powdered  leaves, 
without  previous  drying  over  lime  or  sulphuric  acid,  used  in  the 
assay.  The  reasons  for  this  were  that  the  maximum  quantity  of 
moisture  present  in  20  grammes  leaves  was  about  2  grammes,  and 
this  was  not  considered  to  be  sufficient  to  interfere  with  the  pene- 
tration of  the  drug  by  the  125  grammes  solvent  used;  the  drying 
of  a  portion  of  the  drug  at  the  generally  accepted  temperature  of 
100°  C.  insured  figures  which  could  afterwards  be  utilized  in  cal- 
culating the  alkaloid  for  a  perfectly  dry  drug  or  for  a  drug  contain- 
ing a  different  per  cent,  of  moisture..  (2)  The  determination  of 
alkaloids  in  the  U.S.P,  plaster  made  it  likely  that  sulphuric  acid 
would  be  preferable  to  hydrochloric  acid,  because  of  the  presence 
of  lead  salts  in  the  plaster,  in  removing  the  alkaloids  from  the  ether- 
chloroform  solution,  hence,  a  diluted  sulphuric  acid  (2  c.c.  H2S04, 
diluted  to  500  c.c.)  was  used.  (3)  It  was  found  impossible  to  obtain 
100  grammes  of  the  ether-chloroform  alkaloidal  solution,  so  that 
20  grammes  drug  were  used  instead  of  25  grammes,  with  the  quan- 
tity of  solvent  unchanged.  (4)  The  extraction  with  diluted  sul- 
phuric acid  and  the  ether-chloroform  extraction  of  the  acid  solution 
were  made  in  4  portions  of  25,  15,  10  and  5  c.c.  each,  the  last  por- 
tion being  used  to  rinse  the  vessels  which  had  contained  the  other 
