18  The  Strength  of  Fluid  Extracts.  {""^^jfrimr' 
then  the  term  "Fluid  Extract"  mean  simply  an  extract-fluid,  and 
very  aptly  characterize  either  the  solid  extract  liquified  to  a  point  at 
which  it  would  be  permanently  fluid,  or  the  original  solution  evapo- 
rated down  to  that  point  ?  Owing  to  the  varying  amount  of  soluble 
medicinal  matter  contained  in  difi'erent  drugs,  fluid  extracts  made  on 
this  plan  would,  as  a  class,  be  very  various  in  strength, — a  given 
quantity  of  one  fluid  extract  representing  one  proportion  of  drug, 
and  another  a  difi'erent  proportion, — practically,  therefore,  so  great 
concentration  is  not  desirable,  and  some  standard  is  necessary  which 
includes  uniformity  of  strength  and  facility  of  preparation,  as  well  as 
adaptability  to  the  wants  of  the  physician.  The  present  standard  of 
sixteen  troy  ounces  to  the  pint  seems  best  to  fulfil  these  requirements. 
Made  of  this  strength,  a  fiuid  extract  of  a  drug  is  its  fluid  represent- 
ative, to  all  medicinal  intents  and  purposes,  the  same  thing  as  the  drug 
itself — superior  to  it,  in  fact,  in  having  a  more  prompt  therapeutic 
action  and  readier  facility  of  administration.  What  more  desirable 
preparation  of  a  crude  drug  could  be  offered  the  medical  profession 
or  their  suff"ering  patients  ? 
But — and  this  is  the  main  question— are  fluid  extracts  of  this 
strength  practicable  ?  Is  their  correct  preparation  within  the  range 
of  the  usual  facilities  of  a  dispensing  establishment  ?  Or  does  it  in- 
volve so  great  an  expenditure  of  time  and  labor,  and  so  great  an 
outlay  for  costly  apparatus,  that  the  already  much  pre-occupied 
pharmacist  may  justly  excuse  himself  from  the  undertaking  ?  While 
protesting  against  any  change  in  the  strength  of  fluid  extracts,  the 
writer  does  not  endorse  the  formulas  given  by  the  Pharmacopoeia  for 
their  preparation.  Indeed,  literally  construed,  they  are  impracticable. 
It  is  practically  impossible,  with  the  usual  facilities  to  be  found  in 
stores, — even  the  best  appointed, — to  reduce  a  drug  to  the  degree  of 
fineness  directed  by  the  Pharmacopoeia.  For  example,  in  the  process 
for  fluid  extract  of  buchu,  the  drug  is  directed  to  be  in  powder 
"moderately  fine,"  i.  e.,  a  powder  that  will  pass  through  a  sieve  of 
fifty  meshes  to  the  inch.  Now  it  is  simply  not  possible  to  accomplish 
this  within  any  reasonable  time,  or  when  any  but  the  smallest 
quantities  are  operated  on.  In  the  experience  of  the  writer  it 
requires  considerable  muscular  exertion  to  obtain  even  one-third  of 
any  given  quantity  (over  a  few  ounces)  in  the  state  of  fineness  directed. 
The  only  practicable  thing  is  to  grind  the  drug  as  fine  as  possible,  and 
sift  it  successively  through  sieves  twenty,  forty,  and  sixty  meshes  to 
