28 
Assay  of  Belladonna  Root. 
I  Am.  Jour.  Pharm. 
(    January,  1901. 
pouring  the  mixture  into  a  separator.  Rinse  out  the  beaker  several 
times  in  the  same  way  with  smaller  quantities  of  the  dilute  acid, 
transferring  each  portion  to  the  separator.  Now  wash  the  acid 
mixture  in  the  separator  by  shaking  with  20  c.c.  and  again  with  1 5  c.c. 
chloroform,  running  the  chloroform  out  as  waste.  Take  care  to  draw 
off  only  the  clear  solution.  Next  rinse  this  waste  chloroform  by 
shaking  very  gently  in  another  separator  with  10  c.c.  dilute  sul- 
phuric acid,  throwing  away  the  chloroform  and  returning  the  acid 
to  the  rest  of  the  acid  washings  in  the  first  separator. 
Neutralize  the  acid  solution  in  the  separator  by  adding  20  c.c.  IO 
per  cent,  ammonia  and  extract  the  alkaloid  by  shaking  with  20  c.c, 
15  c.c.  and  10  c.c.  chloroform  exactly  as  in  the  root  assay.  There 
will  be  a  very  considerable  quantity  of  brown  flocculent  material 
collected  at  the  line  of  separation,  floating  in  the  chloroform  and 
extending  down  through  it  so  that  sometimes  only  very  little  clear 
chloroform  solution  can  be  drawn  off  at  first.  As  nothing  must  be 
removed  but  this  clear  solution,  it  will  often  require  as  much  as  an 
hour  to  complete  each  separation,  although  it  can  be  done  more 
quickly  with  some  samples.  The  use  of  stearic  acid  is  usually  neces- 
sary in  these  separations,  for  in  many  cases  emulsification  is  so  com- 
plete that  the  liquids  would  never  separate  without  its  aid. 
When  separation  begins  the  only  way  to  work  is  to  draw  off  the 
first  clear  part,  bringing  the  floating  material  down  to  the  top  of  the 
hole  in  the  stop-cock;  then  by  rocking,  twirling  and  tapping,  fol- 
lowed by  several  minutes'  standing,  the  floating  material  will  draw 
up  or  float  to  the  top  of  the  chloroform,  packing  together  or  solidi- 
fying so  to  speak,  and  leaving  some  more  of  the  clear  chloroform  to 
be  drawn  off  as  before. 
The  same  procedure  is  repeated  generally  five  or  six  times  with 
each  separation  until  the  bulk  of  the  flocculent  sediment  is  reduced 
in  size  as  much  as  possible,  after  which  the  next  portion  of  chloro- 
form is  added  to  the  separator,  shaken  up  and  separated  little  by 
little  in  the  same  way. 
After  the  third  separation  is  done  add  about  10  c.c.  chloroform 
and  draw  it  off  without  shaking,  adding  it  to  the  rest  as  before,  this 
being  done  to  dilute  the  small  amount  of  alkaloid  solution  remain- 
ing in  the  separator,  so  that  the  loss  will  be  inappreciable. 
Shaking  out  the  extract  in  this  way  consumes  considerably  more 
time  than  is  the  case  with  the  assay  of  the  root  direct,  due  to  the 
