FORMULAE  FOR  THE  FLUID  EXTRACTS. 
533 
Remarks. — In  this  class  are  placed  the  narcotic  leaves,  and 
certain  oleoresinous  substances.  Aconite  and  Valerian  will  repre- 
sent them.  When  these  substances,  reduced  to  a  powder  that 
will  pass  a  sieve  of  60  meshes  to  the  linear  inch,  are  uniformly 
moistened,  by  rubbing,  with  a  fourth  of  their  weight  of  the  al- 
coholic mixture,  they  are  yet  pulverulent,  but  exhibit  a  damp 
appearance,  and  readily  pack  in  the  percolator.  Glass  funnels 
answer  a  good  purpose,  but  cylindrical  percolators  may  be  em- 
ployed. In  either  case,  if  the  powder  has  been  properly  com- 
pacted, the  menstruum  when  added  passes  very  deliberately,  by 
drops,  and  it  will  be  found  that  the  proportion  of  the  percolate 
which  is  directed  to  be  reserved  will  contain  nearly  all  of  the 
most  valuable  parts  of  the  drug.  In  this  way  the  action  of  heat 
and  air  is  entirely  prevented  on  the  most  important  part  of  the 
extracted  matter,  and  where  volatile  oils  are  concerned  this  fact 
is  particularly  important.  It  is  surprising  what  concentrated 
liquors  are  thus  obtained  when  the  trouble  is  taken  to  pass  the 
powder  through  a  sieve  of  the  fineness  indicated.  It  will  be  ob- 
served that  the  process  adopted  for  this  class,  is  nearly  that  of 
Prof.  Graham,  for  fluid  extract  of  Valerian.  It  will  require 
strict  attention  to  the  details  of  the  process  to  get  the  results 
intended,  because  success  depends  on  the  slowness  of  the 
percolation  without  any  regulation  at  the  outlet  of  the  funnel. 
The  alcoholic  condition  of  the  resulting  preparations  is  nearly 
50  per  cent.  In  this  fluid  the  chlorophylle  is  but  partly  soluble, 
and  much  of  this  principle  is  left  in  the  exhausted  residue. 
Class  Second. 
EXTRACTUM  ACONITI  RADICIS  FLUIDUM. 
Take  of  Aconite  root,  in  powder,  (No.  60)  16  ounces,  Troy, 
Alcohol,  (sp.,  gr.  -835)  a  sufficient  quantity. 
Moisten  the  powder  with  six  fluid  ounces  of  alcohol,  pack 
it  firmly  in  a  cylindrical  percolator,  cover  the  surface  with  a 
disc  of  cloth,  and  gradually  pour  on  alcohol  until  three  pints  of 
tincture  have  passed,  reserving  the  first  half  pint.  The  re- 
mainder of  the  tincture  is  then  distilled  till  reduced  to  half  a 
pint  and  while  hot  mixed  with  the  reserved  tincture.  After 
standing  twenty-four  hours  filter  through  paper. 
