1 64  Contributions  from  H.  M.  G or  din,  {AmApTif;imrm' 
METHOD  A. 
Ten  grammes  of  the  drug  in  No.  6o  powder  are  put  into  a  Dun- 
stan  and  Short  apparatus,1  and  extracted  with  alcohol  (95  per 
cent.)  for  about  three  to  four  hours  on  the  asbestos  plate.  Most  of  the 
alcohol  is  then  distilled  offfrom  a  water-bath,  and  when  the  extract  is 
reduced  to  about  10  c.c,  it  is  cooled  and  diluted  with  water  contain- 
ing about  1-2  per  cent,  sulphuric  acid.  The  liquid  is  then  poured 
into  a  50  c.c.  or  a  100  c.c.  measuring  flask,  washing  the  vessel  in 
which  the  boiling  took  place,  and  filling  up  the  flask  to  the  mark 
with  acidulated  water.  The  liquid  is  now  shaken  with  a  little  tal- 
cum, filtered,  and  in  25  c.c.  of  the  filtrate  the  alkaloids  estimated  by 
passing  through  immiscible  solvents,  using  either  ammonia  or 
sodium  hydrate  for  the  liberation  of  alkaloids  and  either  ether 
alone  or  a  mixture  of  ether  and  chloroform  in  the  right  proportions 
to  take  up  the  alkaloids.  In  the  case  of  hydrastis,  a  little  potassium 
iodide  is  added  before  filling  the  flask  up  in  order  to  remove  ber- 
berine.  The  alkali  used  to  liberate  the  alkaloid  is  in  most  cases 
ammonia,  except  in  the  case  of  cinchona,  where  it  was  found  that 
ammonia  gives  rise  to  an  emulsion,  whereas  sodium  hydrate  works 
very  well.  If  a  fixed  alkali  be  used,  it  is  necessary  to  shake  up  the 
ethereal  solution  of  the  alkaloid  with  calcined  magnesia,  and  filter 
in  order  to  remove  the  last  traces  of  alkali.2  After  distilling  off  the 
ethereal  liquid  the  alkaloids  are  estimated  by  the  general  alkali- 
metric  method,  referred  to  in  the  beginning  of  this  article. 
METHOD  B. 
This  consists  in  digesting  the  drug  in  very  fine  powder  with  ten 
times  its  amount  of  Prollius'  fluid  modified,3  putting  the  mixture 
into  a  mechanical  shaker  for  four  hours,  or  shaking  frequently  dur- 
ing twelve  hours,  drawing  off  an  aliquot  part,  and  shaking  out  with 
acid  water.    The  alkaloids  are  then  set  free  by  ammonia,  or  Na- 
lPharm.J.  (3),  XIII,  664  ;  Allen,  "Org.  Anal."  3d ed.,  Vol.  II,  Parti,  page  21. 
This  apparatus  is  far  superior  for  hot  extraction  to  the  ordinary  Soxhlet.  The 
temperature  of  the  menstruum  is  higher  and  the  working  of  the  apparatus  sim- 
pler and  always  continuous.  It  is  only  necessary  to  have  the  menstruum  boil  so 
quickly  that  the  drug  is  always  covered  with  liquid,  and  to  put  a  piece  of 
cotton  and  then  a  heavy  piece  of  glass,  or  better,  a  piece  of  lead,  on  top  of  the 
drug. 
2  Arch,  d' Pharm.,  1900,  336. 
3Lvons'  "Handbook,"  1899,  23. 
