4         PEEPARTIONS  OF  DEODOKIZED  TINCTURE  OF  OPIUM. 
As  regards  the  alleged  advantage  of  the  vacuum  in  removing 
air  particles  that  prevent  the  contact  of  the  solvent  and  pow- 
der in  the  cellules  of  the  drug,  it  maj  hold  good  in  unbroken 
tissues,  as  in  kyanizing  wood  with  metallic  solutions  ;  but  in 
operating  with  a  fine  powder  so  closely  packed  as  to  render  the 
action  capillary,  this  air  is  driven  out  by  the  descending  liquid 
like  a  piston  in  a  syringe,  and  its  place  temporarily  occupied  by 
the  liquid,  which  in  its  turn,  by  gravity  and  pressure  of  the 
column  above,  passes  down  from  particle  to  particle,  invading  the 
ruptured  cell  structure  of  each  till  it  attains  saturation,  after 
which  it  does  not  increase  in  density.    There  is  much  to  be 
learned  in  the  relation  of  solvents  to  organic  matter  in  the  pro- 
eess  of  percolation,  and  its  practice  is  so  entirely  adapted  to  the 
shop  and  within  the  ability  of  the  pharmaceutist  to  study  with 
care  and  advantage,  that  it  is  greatly  to  be  desired  that  it  will 
be  retained  as  the  process  of  solution  par  exeellaneey  and  not 
substituted  by  mechanical  methods  dependent  on  costly  appara- 
tus, and  vvhich  necessarily  throws  the  preparation  of  many  im- 
portant classes  of  medicines  into  the  hands  of  large  manufac- 
turers.   Further,  we  do  not  believe  that  evaporation  necessitates 
destruction  of  medicinal  power,  when  properly  conducted,  bj 
adapting  the  method  and  temperature  to  the  nature  of  the  sub- 
stance treated. 
EEMARKS  ON  THE  PREPARATION  OF  DEODORIZED 
^TINCTURE  OF  OPIUM. 
By  Philip  L.  Milleman. 
The  May  number  (1867)  of  the  A7nerican  Journal  of  PJiar- 
Tiiacy^  contains  a  paper  by  Albert  E.  Ebert,  on  deodorized  tinc- 
ture of  opium,  wherein  he  advocates  the  use  of  benzine  for  that 
of  ether,  as  a  means  of  deodorizing  this  valuable  preparation  of 
li^pium.  SinceHhe  publication  of  this  paper,  I  have  frequently 
had  occasion  to  make  this  tincture  in  large  quantities,  and  have, 
hy  following  BIr.  Ebert's  process,  been  successful  in  producing  a. 
5miform  and  good  preparation. 
I  therefore  endorse  the  advantages  the  author  claims  for  his 
process  over  that  of  the  U.  S.  Pharmacopoeia  in  regard  to  time 
