ON  FLUID  EXTRACT  OF  BUCHU. 
349 
and  the  molybdenum  is  converted  into  molybdic  acid  which  is 
afterwards  dissolved  in  ammonia ;  this  operation  is  usually  car- 
ried on  in  an  obliquely  placed  platinum  crucible,  the  mass  being 
frequently  stirred,  but  it  is  very  tedious.  The  improvement  of 
this  method  lately  described  by  Wohler,  in  which  a  draught  of 
air  produced  by  an  aspirator  is  employed,  also  effects  the  ob- 
ject, but  slowly.  The  reason  of  this  is  to  be  found  partly  in  the 
difficulty  of  dividing  the  material  sufficiently,  as  it  always  cakes 
together  again  when  heated,  and  partly  in  the  fact  that  the  mo- 
lybdic acid  produced  covers  the  residue  of  the  mineral  and  thus 
renders  its  ignition  difficult. 
The  operation  may  be  effected  very  easily  in  the  following 
way  : — The  sulphuret  of  molybdenum  is  triturated  in  an  agate 
mortar  with  an  equal  volume  of  coarse  quartz.sand  washed  with 
muriatic  acid  until  it  forms  a  moderately  fine  powder,  which  is 
placed  in  a  shallow  platinum  cup  or  on  platinum  foil,  and  heated 
over  a  good  spirit-lamp  to  the  commencement  of  incandescence, 
stirring  it  frequently  until  the  mixture  has  acquired  a  citron- 
yellow  color  (whitish,  on  cooling).  A  quarter  of  an  hour  is 
sufficient  to  effect  this  with  several  grammes  of  the  mixture. 
When  cool,  the  mass  is  extracted  with  liquid  ammonia  and  fur. 
ther  treated  in  the  usual  way. — London  Chem.  Cfaz.  April  15? 
from  Dingier' 's  Polyt.  Journal,  cl.  p.  72. 
ON  FLUID  EXTRACT  OF  BUCHU. 
By  Israel  J.  Grahame. 
Among  the  important  preparations  of  the  class  here  alluded 
to,  not  included  in  the  officinal  list,  is  the  fluid  extract  of  buehu. 
Although  a  preparation  of  nostrum  celebrity  had  long  been  in 
use  under  this  name,  but  which  possessed  very  little  of  the 
characteristics  of  the  plant  it  professed  to  represent,  it  was  not 
till  after  the  adoption  of  the  present  Pharmacopoeia,  that  Wm. 
Procter,  Jr.,  proposed  a  formula  for  its  preparation  in  accord- 
ance with  the  peculiar  properties  of  the  drug,  since  which  time 
it  has  been  extensively  used  in  medical  practice,  and  made  mostly 
by  his  process  or  with  slight  modifications  of  it.  It  is  one  of 
those  fluid  extracts  which  require  the  use  of  an  alcoholic  sol- 
