THE 
AMERICAN  JOURNAL  OF  PHARMACY. 
JANUARY,    187  2. 
ILLUSTRATIONS  OF  SOME  PHARMACEUTICAL  PROCESSES 
AND  APPARATUS, 
As  Exhibited  to  the  Class  in  the  Philadelphia  College  of  Pharmacy. 
By  Prof.  E.  Parrish. 
The  illustration  of  a  course  of  lectures  in  Pharmacy  gives  an  op- 
portunity for  noting  carefully  details  and  results  which  in  common 
practice  are  overlooked  or,  if  observed,  are  not  made  public. 
The  processes  detailed  in  this  essay  were  conducted  at  the  Phila- 
delphia College  of  Pharmacy,  in  presence  of  the  large  class  of  stu- 
dents, with  such  facilities  only  as  a  lecture-room,  with  its  counter, 
sink,  hydrant,  and  gas-supply  afford. 
The  energies  of  the  lecturer  being  mainly  directed  to  explanation 
and  oral  instruction,  an  assistant  is  employed  in  the  management  of 
the  several  processes  simultaneously  going  on  during  the  lecture;  to 
his  skilful  assistant,  Jos.  P.  Remington,  the  writer  acknowledges 
himself  indebted  for  useful  suggestions,  especially  in  the  construction 
of  the  steam  evaporating  apparatus  herein  described. 
Immediately  after  a  statement  of  the  scientific  facts  and  principles 
pertaining  to  the  generation  and  application  of  heat  in  pharmacy, 
the  process  of  evaporation  and  the  apparatus  suitable  for  the  prepa- 
ration of  extracts  are  brought  into  view,  models  and  drawings  are 
used  for  some,  while  evaporating  dishes,  sand-baths,  steam-baths  and 
water-baths  are  shown  in  actual  use. 
The  annexed  drawing  shows  a  steam-boiler,  evaporating  pan  and 
still-head  constructed  for  the  purposes  of  this  course  of  instruction.  A 
is  a  boiler  of  J  inch  thick  (No.  10  wire  gauge),  copper,  1  foot  9  inches 
long  by  7  inches  in  diameter.    It  is  held  in  position  by  a  stout  iron 
