NOTES  ON  THE  FLUID  EXTRACTS  OF  BUCHU,  ETC.  318 
the  gradual  addition  of  a  very  small  quantity  of  menstruum, 
from  2  to  4  oz.  to  16  oz.  material,  for  an  hour  or  two,  to  enable 
the  coarser  particles  to  absorb  thoroughly  the  liquid  with  which 
they  had  been  moistened  ;  liquor  was  then  poured  upon  the  fil- 
tering paper  and  the  percolation  allowed  to  proceed. 
Buchu  leaves,  on  account  of  their  tenacity,  are  hard  to  pul- 
verize ;  exposure  to  heat  and  subsequent  powdering  in  a  cool 
mortar  would  greatly  facilitate  it,  but  is  inadmissible  on  account  of 
the  loss  of  the  volatile  principle.  By  some  labor  with  the  mill 
and  the  mortar  1  succeeded  in  getting  them  fine  enough  to  pass 
nearly  all,  without  any  pressure,  through  a  sieve  of  12  meshes 
to  the  inch  ;  the  remainder,  about  one-eighth  or  less,  was  not 
farther  pulverized  ;  the  percolator  was  packed  as  before,  and 
displacement  commenced  as  soon  as  the  coarse  powder  had  fairly 
began  to  swell  up. 
I  think  it  will  be  necessary,  advisable  at  least,  to  state  in  the 
next  Pharmacopoeia  the  degree  of  fineness  of  the  powder  to  be 
used  in  the  displacement  process  ;  so  as  to  induce  pharmaceutists 
to  perform  this  labor  themselves,  instead  of  buying  the  powder  ; 
the  officinal  directions  must  not  be  made  unnecessarily  laborious. 
As  the  material  on  top  of  the  percolator  is  exhausted  first,  it  is 
advisable  to  assign  this  place  to  the  coarsest  of  the  powder. 
After  these  general  explanations  I  proceed  to  give  you  the 
formulae  which  I  employed  : 
f  Extraetum  Buchu  fluidum.—lQ  ounces  of  buchu  leaves  are 
percolated  with  a  mixture  of  6  fl.  oz.  of  ether  and  12  fl.  oz. 
alcohol,  to  be  displaced  until  18  fl.  oz.  are  obtained,  which  tinc- 
ture is  evaporated  spontaneously  to  3  fl.  oz. ;  the  precipitated 
chlorophylle  is  dissolved  in  3  fl.  oz.  alcohol,  and  both  liquids  are 
mixed  with  12  oz.  sugar ;  meanwhile  the  residue  in  the  percola- 
tor is  exhausted  with  diluted  alcohol,  (about  12  oz.  will  be  suffi- 
cient,) the  tincture  evaporated  to  4  fl.  oz.  added  to  the  sugar, 
which  is  dissolved  by  a  moderate  heat  and  the  extract  strained. 
Extractum  Cimieifugce  fluidum  16  oz.  of  the  root  are  ex- 
tracted with  a  mixture  of  8  fl.  oz.  ether  and  1  pint  of  alcohol, 
and  left  to  evaporate  to  2  fl.  oz.,  which  are  dissolved  in  6  fl.  oz. 
of  alcohol ;  8  oz.  of  sugar  are  made  to  absorb  the  solution.  The 
residue  of  the  root  is  exhausted  by  diluted  alcohol,  the  resulting 
