196 
Correspondence. 
J  Am.  Jour.  Pharm. 
\      April,  1910. 
of  cardamom.  The  conclusions  drawn  from  these  experiments  are 
as  follows :  The  present  U.S. P.  method  is  entirely  unsatisfactory. 
Besides  having  the  shortcomings  of  all  maceration  processes  the 
product  was  filtered  with  great  difficulty ;  and  the  nitrate  was  by 
no  means  as  bright  and  clear  as  that  made  by  percolation.  I  did 
not  observe  much  difference  in  the  quantity  of  deposit,  on  standing. 
The  addition  of  glycerin  to  the  menstruum  previous  to  extraction 
only  serves  to  increase  the  proportion  of  inert  extractive.  It  should, 
I  believe,  be  added  after  percolation. 
In  the  preparation  of  tincture  of  opium  the  drug  could  be  ex- 
tracted more  readily  if  it  were  mixed  with  some  inert  non-adhesive 
material,  like  purified  sawdust  or  powdered  paper.  In  this  con- 
nection it  might  be  well  to  mention  that,  in  my  experience,  it  is 
difficult  to  completely  exhaust  opium  by  the  prescribed  amount  of 
menstruum  and  I  would  suggest  that  it  might  be  well  to  percolate 
the  drug  to  exhaustion  with  a  suitable  menstruum  after  having 
set  aside  a  reserve  portion ;  the  weak  percolate  being  evaporated 
to  a  soft  extract  and  dissolved  in  the  reserve  percolate,  etc. 
Tincture  of  aloes  and  compound  tincture  of  lavender  now  pre- 
pared by  maceration  are  both  suitable  for  the  process  of  percolation. 
Referring  to  percolation,  I  may  state  without  hesitation  that 
this  method  of  extracting  drugs  appeals  to  me  very  forcibly.  It 
should  be  preceded,  as  is  invariably  directed  by  the  leading  author- 
ities, by  sufficient  maceration  to  soften  and  disintegrate  the  cellular 
tissue,  within  which  the  extractive  matter  is  enclosed.  Indeed 
maceration  to  this  extent  is  a  part  of  the  process  of  percolation. 
This  process,  in  my  opinion,  avoids  almost  entirely  the  objections 
offered  to  the  modus  operandi  of  maceration.  Even  the  temptation 
to  abstract  portions  of  the  unfinished  product  is  obviated  because  of 
the  comparatively  less  length  of  time  required  for  completion  of  the 
process  when  once  in  active  operation.  Yet  it  is  true  that  the  time 
of  maceration,  before  percolation,  may  be  cut. 
The  entire  theory  of  percolation  is  convincing  and  I  believe  the 
theory  is  well  borne  out  in  practice.  I  know  of  no  serious  ob- 
jection to  this  process  unless,  as  I  have  sometimes  heard  stated, 
the  final  product  after  standing  showrs  a  greater  proportion  of  inert 
sediment  than  does  a  like  preparation  made  by  maceration.  This 
may  be  true,  due  to  the  action  of  solutions  of  extractive  matter 
of  different  degrees  of  saturation  upon  different  portions  of  the 
drug  and  the  subsequent  mixing  of  same.    However,  I  have  ob- 
