AmMay?Sarm'}       U.  S.  and  Br.  Pharmacopoeias.  227 
are  really  weak  tinctures,  as  they  are  mostly  made  by  percolation 
with  20  per  cent,  alcohol.  It  comprises  those  of  calumba,  cusparia, 
krameria,  quassia,  rheum,  sarsaparilla  comp  ,  senega,  senna  and 
serpentaria,  tabella  trinitrin  (nitroglycerin  tablets),  each  contain 
chocolate  5  grains  and  grain  nitroglycerin.  The  comparative 
strength  of  the  acids  is  exhibited  in  the  following  table  : 
U.S. P.  BP. 
Acid  Acetic  by  weight   36*  33' 
"       "      Dil.  "  .........     6-  4-27 
"       "       Glacial  "    gg'-ioo'  99- 
"    Hydrobromic  Dil.          "    io*  io* 
"    Hydrochloric  "    31  9  31 '79 
'            "  Dil.         "    io-  10-58 
"    Hydrocyanic  "           "    2.  2 
h    Lacticum  "    75-  75- 
"    Nitricum  "       .   68*  70" 
"        "         Dil.    io*  17*44 
"    Phosphoricum  "   85'  66-3 
"          '>*'  Dil.         'f  ..........  io-  13-8 
"    Sulphuricum  •              "    92*5  98' 
"  Dil.         "   io-  1365 
"    Sulphurosum  "   6*4         6  "4 
Of  the  extracts  B.P.  three  are  standardized,  and  two  (Ext.  Bellad. 
Viride  and  Ext.  Hyoscyam.  Viride)  are  made  from  green  drugs. 
The  strength  of  the  fluid  extracts  is  the  same  in  both  Pharmaco- 
poeias, viz.,  1  gramme  of  the  drug  to  1  c.c.  The  U.S. P.  is  especially 
rich  in  this  class  of  preparations,  there  being  an  excess  of  72  over 
the  number  in  the  B,P.,  only  one  (nux  vomica)  being  standardized 
to  five  of  the  B.P.,  viz.,  belladonna,  cinchona,  ipecac,  nux  vomica 
and  opium.  The  B.P.  is  especially  rich  in  infusions  and  ointments. 
Percolation  does  not  seem  to  be  making  headway  across  the  water, 
as  in  the  former  B.P.  47  tinctures  out  of  77  were  made  by  percola- 
tion; in  the  new  B.P.,  30  out  of  67.  The  tinctures  in  the  B.P. 
which  are  made  by  percolation  are  mostly  made  after  a  general  for- 
mula, no  special  directions  being  given  in  the  individual  formula  for 
packing  the  drug  in  the  percolator,  the  matter  being  left  to  the 
judgment  of  the  operator.  This,  it  seems  to  me,  is  a  very  impor- 
tant omission,  which  may  affect  the  result  in  a  number  of  cases. 
Another  difference  is  that  the  B.P.  directs  the  marc  to  be  ex- 
pressed, the  liquid  thus  obtained  to  be  filtered  and  added  to  the 
percolate,  sufficient  menstruum  then  being  added  to  produce  the 
required  volume  of  tincture.    Eight  of  the  tinctures  of  the  B.P. 
