30 
PHARMACEUTICAL  NOTES. 
hydro-alcoholic  class  would  not  yield  all  their  active  principle, 
in  sixteen  fluid  ounces  of  percolate  from  sixteen  troy  ounces  of 
the  drug. 
Rhubarb  was  taken  for  the  experiment.  The  root  was  pow- 
dered in  a  Swift's  drug-mill  and  passed  through  a  sieve  of  forty 
meshes  to  the  linear  inch,  until  sixteen  troy  ounces  were  obtained  ; 
this  was  moistened  with  a  menstruum  composed  of  two  parts 
alcohol,  one  part  water  and  one  part  glycerin,  three  fluid  ounces 
being  sufficient.  It  was  then  carefully  packed  in  a  funnel  pre- 
pared for  percolation,  the  surface  covered  with  a  piece  of  filter- 
ing paper,  and  thirteen  fluid  ounces  of  the  menstruum  above 
described  poured  over  it. 
Twenty-four  hours  showed  that  the  sixteen  ounces  of  liquid 
used  was  not  sufficient  to  descend  through  the  powder. 
Finding  that  the  menstruum  was  all  absorbed  and  its  descent 
stopped,  sufficient  dilute  alcohol  was  added,  after  the  expiration 
of  thirty-six  hours,  to  uniformly  moisten  the  drug.  Six  ounces 
more  were  required — the  sixteen  troy  ounces  of  rhubarb  requir- 
ing twenty-two  ounces  of  liquid. 
After  macerating  for  the  length  of  time  specified  by  Mr.  C., 
dilute  alcohol  was  added  until  sixteen  ounces  of  percolate  were 
obtained.  This  was  a  dark  strong  extract  of  rhubarb,  but  the 
drug  was  not  exhausted,  eight  ounces  more  being  required. 
The  result  of  the  experiment  agrees  nearly  with  those  of  Mr. 
Reynolds,  reported  in  the  Nov.  No.  of  the  Journal. 
The  suggestion  to  allow  maceration  for  several  days  before 
percolating  is  a  good  one,  as  less  menstruum  will  be  required 
for  the  complete  exhaustion  of  the  drug. 
3Iiddletown,  N,  T.,  Dec,  1869. 
PHARMACEUTICAL  NOTES. 
By  Wm.  Silver  Thompson. 
Vallefs  Protocarhonate  of  Iron. 
In  the  U.  S.  Pharmacopoeia  of  1860  this  preparation  is  called 
"  Pills  of  Carbonate  of  Iron."    This  was  probably  an  oversight 
on  the  part  of  the  framers  of  that  work,  as  it  does  not  direct  the 
mass  to  be  made  into  pills. 
