76 
Eupatorium  Purpureum. 
(Am.  Jour.  Pharm. 
[       Feb.,  1890. 
pared  sample,  followed  somewhat  later  at  my  request  by  this 
report : 
"  Concerning  the  yellow  crystalline  principle  of  Eupatorium 
purpureum,  I  will  say  that  it  was  first  obtained  by  me  between 
the  years  1870  and  1875,  I  cannot  give  exact  date  of  discovery. 
For  some  time  it  remained  a  private  cabinet  specimen  only, 
but  finally  I  forwarded  a  sample  to  Prof.  Maisch  for  his 
cabinet,  and  he  donated  it  to  the  Philadelphia  College  of 
Pharmacy."1 
"This  material  belongs  to  the  class  of  organic  bodies  that, 
after  once  having  been  separated  from  natural  associations, 
present  marked  characteristics,  but  which  persistently  refuse 
to  assert  to  their  individualities  while  in  the  society  of  accom- 
panying extractives.  Hence,  in  endeavoring  to  crystallize 
it  from  any  natural  extractive  liquid,  the  experience  of  the 
investigator  is  discouraging,  for  it  assumes  an  amorphous 
condition  as  a  part  of  the  extractive,  and  redissolves  when 
the  extractive  matter  is  dissolved  without  exhibiting  itself, 
even  to  the  microscopist. 
"In  order  to  prepare  it,  I  employ  the  principle  that  I  have 
learned  is  often  desirable  in  liberating  plant  constituents, 
i.  e.,  the  preliminary  separation  of  extraneous  extractives  and 
then  crystallization  of  the  desired  substance  from  an  appro- 
priate menstruum.  Under  these  conditions  the  principle 
under  discussion  is  easily  developed,  and  afterwards  exhibits 
a  marked  separate  existence,  being  indeed  characterized  by  a 
strong  tendency  to  separate  in  beautiful  crystalline  tufts 
immediately  upon  the  reduction  of  temperature  of  its  hot 
alcoholic  solution. 
"  Preparation. — Exhaust  finely  ground  or  powdered  root  of 
Eupatorium  purpureum  in  a  menstruum  composed  of  three 
parts  of  alcohol  and  two  parts  of  water.  Evaporate  the  per- 
colate to  the  consistence  of  thick  honey,  and  pour  it  into 
cold  water,  stirring  well.  After  a  day  (or  when  the  dark- 
colored  precipitate  has  subsided)  decant  the  overlying 
aqueous  solution  and  wash  the  precipitate  with  a  fresh  por- 
1  This  specimen  is  still  in  the  College  Museum  and  was,  with  the  other 
crystals,  exhibited  at  the  reading  of  this  paper. 
