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Modification  of  the  Soxhlet  Extractor. 
Am.  Jour.  Pharm. 
March,  1908. 
MODIFICATION  OF  THE  SOXHLET  EXTRACTOR. 
By  Horatio  C.  Wood,  Jr., 
Associate  Professor  of  Pharmacology,  University  of  Pennsylvania. 
The  apparatus  here  shown  for  continuous  extraction  by  volatile 
solvents  has  proven  itself  efficient  and  offers  certain  advantages 
over  the  Soxhlet  extractor,  notably  in  its  simplicity  and  inexpen- 
siveness.  It  consists  of  a  narrow  percolator  (P)  the  lower  end  ot 
which  is  connected  by  means  of  a  tightly  fitting  cork  with  a  siphon- 
shaped  glass  tube,  and  the  upper  end  closed  with  a  perforated  cork 
into  which  is  fitted  a  glass  "  T  "  tube.  The  rectangular  limb  of  this 
tube  is  connected  by  a  very  short  piece  of  rubber  with  a  glass  tube 
Modified  Soxhlet  Extractor. 
bent  at^rightjangles  which  passes  down  to  the  flask  containing  the 
solvent.  When  the  contents  in  the  flask  (F)  are  boiled,  the  vapors 
pass  up  through  the  tube  (A)  into  the  tube  (T) ;  the  upper  end  of  (T) 
is'connected  with  a  reflux  cooler  into  which  the  vapors  pass  and, 
being'condensed,  run  down  into  the  percolator  (P)  and  thence  back 
through  (S)  into  the  flask. 
Besides  the  advantages  over  the  Soxhlet  apparatus  of  being  less 
expensive  and  much  less  fragile,  the  facts  that  by  simply  removing 
the  corks  in  each  end  of  the  percolator,  the  apparatus  can  be  easily 
and  quickly  cleaned,  and  that  by  simply  substituting  different  sizes 
of  percolators  it  can  be  adapted  for  either  large  or  small  quantities 
of  drugs  with  comparatively  little  trouble,  have  persuaded  me  to 
describe  it. 
