1 82  Powdered  Medicinal  Extracts.       { ^m gj™- 
color  and  enjoys  perhaps  a  larger  sale  than  any  other;  it  was  labelled 
to  contain  the  full  quantities  of  ingredients. 
No.  10  was  a  syrup,  and  labelled  to  contain  I  grain  phosphate  of 
iron,  grain  muriate  of  quinine,  other  phosphate  and  free  phos- 
phoric acid  to  a  fluid  drachm. 
Nos.  II  and  12  were  chemical  food  or  syrup  of  phosphates,  and 
should  contain  1  gr.  phosphate  of  iron  to  each  fluid  drachm. 
POWDERED  MEDICINAL  EXTRACTS. 
By  William  B.  Thompson. 
Solid  extracts  of  vegetable  drugs  to  be  of  requisite  quality 
should  possess,  in  a  marked  degree,  the  distinguishing  characteris- 
tics of  the  material  of  which  they  are  made.  Each  should  present 
a  distinctive  individuality,  and  in  those  substances  in  which  the 
active  constituent  is  alkaloidal,  precise  assay  should  show  a  full 
average  percentage.  Odor  and  taste  should  be  wholly  preserved, 
and  that  excess  of  inert  matter,  usually  denominated  "  extractive  " 
and  largely  predominating  in  this  class  of  articles  as  usually  found, 
should  be  avoided  or  materially  diminished  by  skill  of  process. 
The  choice  of  a  proper  solvent  or  menstruum  for  the  active  prop- 
erties of  a  drug  involves  experience  and  extended  observation. 
Error  in,  or  indifference  to,  this  essential  is  quite  likely  to  result  in 
a  minimum  of  active  constituent  loaded  with  a  maximum  of  ''extrac- 
tive." Both  physician  and  pharmacist  will  realize  that  this  means 
a  gain  in  bulk  and  weight,  and  thereby  a  commercial  advantage, 
but  the  therapeutic  purpose  and  object  are  lessened  to  a  culpable 
degree.  The  initial  point,  of  course,  in  this,  as  in  all  other  classes 
of  finished  pharmaceutical  products,  is  the  selection  of  good,  sound 
drugs — a  quality  of  which,  better  than  the  average,  is  not  too 
good,  and  often  not  good  enough.  Then  the  process,  in  all  its 
detail,  of  reduction  from  liquid  to  solid,  should  be  carried  from 
beginning  to  full  completion,  within  the  vacuum  still  or  vessel,  at 
such  controlled  or  regulated  temperature  that  heat  can  in  nowise 
prove  a  destructive  element.  As  complete  an  exclusion  of  sur- 
rounding atmosphere  as  is  possible  precludes  that  tendency  which, 
it  is  known,  induces  a  change  in  the  state  of  single  and  associated 
alkaloids,  and  disturbs  that  nice  adjustment  in  which  these  exist  in 
a  native  or  natural  condition.  With  the  application  of  a  proper  degree 
