544        PREPARING  CERTAIN  PHARMACEUTICAL  EXTRACTS. 
by  sulphuretted  hydrogen,  or  by  zinc  as  a  metal  resembling  me- 
tallic tin. — Ohem.  News,  London,  July  26,  1862. 
ON  A  METHOD  OP  PREPARING  CERTAIN  PHARMACEUTICAL 
EXTRACTS. 
By  M.  Pierlot. 
M.  Pierlot's  process  is  especially  valuable  in  preparing  extracts 
of  aromatic  plants,  their  useful  principles  being  necessarily 
dissipated  during  the  preparation  of  extracts  by  the  ordinary 
method.  It  might  pass  for  an  ingenious  application  of  M.  Mil- 
Ion's  researches  on  the  subject  of  vegetable  perfumes  if  the 
author,  who  does  not  quote  M.  Millon,  did  not  appear  to  be 
unaware  of  his  work. 
Into  a  displacement  apparatus,  a  fresh  plant,  such  as  absinthe, 
tansy,  milfoil,  chamomile,  primrose  root,  valerian  root,  &c,  is 
introduced,  and  covered  with  ether,  which  gradually  expels  the 
water  of  vegetation,  and  retains  the  volatile  aromatic  principles 
of  the  plant.  The  displaced  water  occupies  the  lower  part  of 
the  funnel,  holding  in  solution  the  extractive  matter,  the  albu- 
men, and  several  saline  principles.  In  proportion  as  it  is  drawn 
off,  the  water  is  replaced  by  fresh  quantities  of  ether,  and  as 
soon  as  the  ether  ceases  to  displace  water  the  plant  is  put  under 
the  press,  and  treated  again  by  ether. 
The  different  quantities  of  ether  which  have  been  used  are 
now  to  be  mixed,  and  distilled  in  a  water  bath  at  30°.  This 
distillation  produces  ether,  with  hardly  any  impregnation,  and 
a  residuary  (formed  of  an  essential  oil,  of  a  bluish  color,  and  a 
greenish-yellow,  resinous,  fatty  matter)  containing  all  the  per- 
fume of  the  plant. 
The  disnlaced  water  contains  the  extractive  matter  and  the 
X 
albumen.  By  shaking  up  with  a  little  alcoholised  ether,  the 
coagulated  albumen  rises  to  the  surface,  and  is  separated  by 
filtration.    The  extractive  matter  is  obtained  by  evaporation. 
The  union  of  these  two  residuums  gives  an  odorous  extract, 
representing  very  exactly  all  the  active  elements  of  the  plant. 
Pharmaceutists  who  attach  an  exaggerated  amount  of  importance 
to  the  appearance  of  their  medicaments  can  object  to  it  only 
on  account  of  its  forming  with  water  turbid  solutions. 
