390 
EiTRACTUM  ANTHEMIDIS  FLUIDUM. 
with  Fluid  Extracts  and  Tinctures  in  a  concentrated  form.  In 
arranging  those  drugs,  of  which  the  active  properties  are  to  be 
extracted,  we  have  to  examine  into  their  constituents,  their  vol- 
atility, &c.,  and  to  select  the  proper  menstrua  best  adapted 
as  solvents.  Nor  is  it  necessary  to  dissolve  the  worthless  con- 
stituents, not  having  any  valuable  properties,  that  we  may  run 
the  risk  to  injure  the  more  active  ones  ;  which  is  often  the  case 
by  employing  a  too  high  heat;  or  exposure  to  a  temperature — 
cold  or  warm — too  long  continued  ;  or  substituting  heedlessly 
one  solvent  agent  for  another,  &c. 
The  active  properties  of  chamomile  flowers  depend  chiefly 
on  a  volatile  oil,  and  bitter  extractive,  little  soluble  in  water 
and  diluted  alcohol,  but  slightly  in  alcohol,  and  very  soluble  in  ab- 
solute alcohol.  The  annexed  formula  for  a  fluid  extract,  accord- 
ing to  the  measurement — fluid  ounce  for  each  troy  ounce — has 
given  me  entire  satisfaction  in  regard  to  a  reliable  strength  and 
quality,  and  is  as  follows  : 
R  Flor.  Anthemidis  3viii.  Troy. 
Alcohol,  deodor.  (sp.  gr.  0-809)  Oiii. 
Fiat  Extr.  Anth.  fl.  gviii. 
As  the  flowers  make  a  considerable  bulk,  no  pains  should  be 
spared  to  reduce  them  to  as  fine  a  powder  as  possible,  by  grinding 
and  contusion. 
Moisten  the  powder  with  one  pint  of  deod.  alcohol  thoroughly, 
and  pack  it  into  a  conical  percolator  of  4  inches  diameter,  and 
16  inches  or  more  in  length  ;  to  increase  the  weight  of  the  dis- 
placing fluid,  I  use  a  heavy  iron  weight.  After  six  hours'  stand- 
ing, displace  with  2  pints  deod.  alcohol,  carefully  preserving 
the  first  4  fluid  ounces.  Evaporate  in  a  porcelain  dish  the  re- 
maining fluid  spontaneously^  at  a  temperature  of  60-70^F.  to  4 
ounces.  As  the  alcohol  evaporates,  a  greenish  resinous  mat- 
ter separates,  which  increases  rapidly  towards  the  end  of  the 
evaporation.  Put  it  all  carefully  into  a  mortar,  and  rub  it  with 
the  first  4  fluid  ounces,  which  dissolve  it;  then  filter,  any  loss  in 
measure  to  be  made  up  with  deod.  alcohol.  This  fluid  extract 
is  of  a  dark  yellowish  color,  very  bitter,  and  has  the  odor  and 
taste  of  the  flowers  in  a  remarkable  degree. 
