246 
Tincture  Deposits. 
A.m.  .Tour,  Phariu. 
May,  1885. 
of  thought  left  uncultivated,  where  would  be  our  mathematicians, 
scientists  or  men  of  business?  So  with  scientific  knowledge.  Use 
what  we  have  for  practical  purposes  and  it  will  increase  in  the  use. 
To  apply  it  to  the  present  case  :  by  the  practical  working  out  of  methods 
of  titration  a  deeper  knowledge  of  the  constitution  of  a  plant  mud 
follow,  which  will  most  certainly  lead  step  by  step  to  a  thorough  know- 
ledge of  its  more  indefinite  constituents.  The  alkaloids  alone  do  not 
represent  the  full  activity  of  a  plant,  but  it  is  fairly  well  established 
that  a  specimen  containing  1  per  cent,  of  alkaloid  is  stronger  than  one 
containing  only  '75  per  cent.,  and  therefore  the  activity  of  a  drug  may 
be  measured  by  that  alkaloid,  since  the  other  constituents  are  present 
in  both  cases. 
This  applies  when  there  is  but  one  alkaloid,  but  when  there  are  two 
or  more,  as  in  cinchona  or  nux  vomica,  the  difficulty  is  greater.  •  In 
these  cases  it  would  perhaps  be  safest  to  standardize  the  most  powerful 
to  a  definite  amount ;  but  the  remaining  alkaloids  should  also  be  kept 
within  safe  limits  by  the  wise  discrimination  of  drugs.  For  example, 
in  the  case  of  nux  vomica  tincture,  '08  per  cent,  of  strychnia  is  the 
average  of  Messrs.  Dunstan  and  Short's  results;  but  I  think  the  nux 
vomica  should  be  so  chosen  as  to  keep  the  brucia  within  the  limits  of 
•10  and  "lo  per  cent.,  the  highest  and  lowest  of  Mr.  Short's  being  "24 
and  'OTo  per  cent.  The  practical  difficulties  of  dilution,  etc.,  urged  by 
Mr.  Scliacht  against  standard  extracts,  cannot  be  applied  to  tinctures, 
since  there  can  be  no  objection  to  a  little  spirit  nwre  or  less.  Mr. 
Schacht  seems  rather  to  indicate  that  the  medical  profession  does  not 
call  for  such  preparations.  If  this  be  the  case  I  wonder  at  the  use  of 
the  alkaloids  at  all ;  why  do  they  not  confine  themselves  to  the  old- 
fashioned  infusions  and  extracts  ?  The  very  fact  of  the  immense  use 
of  alkaloids  shows  plainly  that  if  standard  tinctures  and  extracts  are 
placed  before  the  medical  profession  they  will  be  largely  and  readily 
prescribed.  One  would  scarcely  expect  a  prescription  to  be  written 
for  standard  tincture  of  opium,  for  instance,  until  some  firm  has  brought 
out  such  a  preparation ;  the  patient  could  scarcely  wait  while  the 
chemist  devised  a  method  for  estimating  it. 
In  regard  to  standard  extracts  which,  like  the  tinctures,  shall  be 
constant  in  strength,  I  have  not  yet  had  sufficient  experience  to  speak 
very  strongly  as  to  their  feasibility,  but  I  hope  soon  to  be  able  to  show 
that  a  series  of  them  is  not  only  desirable  but  also  possible. — Pharm. 
Jour,  and  Trans.,  March  21,  1885,  p.  769. 
