Am'sJeptr;Sarm'}      Tinctures  from  Fluid  Extracts.  439 
If  fluid  extracts  are  to  serve  the  double  purpose  of  being  used 
for  making  tinctures  and  also  for  their  own  virtues,  it  is  essential 
that  they  contain  all  the  soluble,  proximate  principles  found  in 
drug-tinctures,  and  in  as  great  relative  proportions. 
Wherever  medicinal  action  obtains,  the  therapeutically-active 
principles  of  a  vegetable  drug  are  soluble  principles,  that  is  soluble 
in  water  or  alcohol,  or  a  mixture  of  the  two.  All  the  soluble  proxi- 
mate principles  of  a  vegetable  drug  are  not  necessarily  therapeutically 
active,  but  in  the  immature  condition  of  the  rational  therapeutics  of 
our  times,  as  to*  the  changes  produced  by  drug-extractives  in 
cellular  contents  in  diseased  conditions,  who  can  say  that  a  given 
extractive  of  a  drug  having  medicinal  activity  is  inert  or  without 
medicinal  value  ?  At  present,  clinical  evidence  decides,  most 
largely,  the  therapeutical  worth  of  a  drug  or  its  preparation. 
The  action  of  a  drug  or  its  representative  is  exerted  upon  the 
cellular  contents  of  human  tissue  or  tissues  in  which  the  drug  acts, 
modifying  one  or  all  of  three  cellular  activities,  i.  e„  (1)  nutritive, 
(2)  functional,  and  (3)  reproductive.  The  functional  activities  of 
cells  being  the  most  obvious,  they  have  been  the  most  carefully 
noted  by  therapeutists,  indeed  the  modern  description  of  the  thera- 
peutical action  of  a  drug  is  almost  wholly  limited  to  a  description  of 
the  functional  disturbances  produced  by  it.  When  it  comes  to  a 
description  of  the  modifying  influence  of  drugs  or  their  representa- 
tives upon  the  nutritive  and  reproductive  activities  of  cells  in  disease, 
modern  therapy  has  little  to  say  in  comparison  with  the  attention 
paid  to  functional  changes.  In  therapeutical  experiments,  unless  a 
change  be  obvious,  it  is  too  often  assumed  that  there  is  no  change, 
and  yet  the  nutrition  and  reproduction  of  the  cell  may  be  notably 
affected  and  not  be  obvious.  Further,  the  activities  of  nutrition  and 
reproduction  are  vitally  connected  with  the  existence  of  the  cell,  and 
most  probably  influence  its  functions ;  nutrition,  certainly,  plays  a 
most  important  part  in  affecting  function. 
In  addition  to  the  necessity  of  fluid  extracts  containing  all  the 
proximate  principles  of  drugs  found  in  drug-tinctures  (z^they  are  to 
be  used  for  making  tinctures),  it  follows,  of  course,  that  they  should 
be  present  in  as  great  a  relative  proportion,  so  that  the  extract-tinc- 
ture and  the  drug-tincture  be  equally  representative  of  the  drug  in 
the  amount  of  proximate  principles  present. 
No  isolated  proximate  principles,  such  as  alkaloids,  glucosides, 
