Am.  Jour.  Pharrn,  1 
Jane,  1898.  J 
Belladonna  Plasters. 
293 
case  was  it  produced  at  blood  heat,  the  lowest  temperature  at  which 
the  action  was  observed  being  65  0  C. 
The  conditions  produced  by  wrapping  a  bandage  in  the  manner 
described  may  lower  the  temperature  of  combustion  somewhat,  but 
as  no  one  cared  to  submit  himself  to  experiment  in  that  direction, 
so  the  occurrence  is  given  as  it  was  noted,  without  verification. 
The  probable  cause  of  the  phenomenon  is  the  presence  of  a  slight 
amount  of  free  sulphuric  acid,  which  is  allowed  by  the  U.S.P.  for  the 
purpose  of  preserving  the  solution.  When  the  experiment  was  tried 
with  hydrogen  peroxide  which  had  previously  been  neutralized, 
little  or  no  charring  effect  was  produced  on  the  material  used,  while 
a  1  per  cent,  solution  of  sulphuric  acid  produced  charring  to  a 
greater  extent  than  the  peroxide  in  the^first  instance. 
In  the  April  number  of  this  journal  the  writer  published  a  paper 
on  this  subject,  in  which  was  included  a  report  on  the  examination 
of  a  number  of  commercial  plasters.  The  most  of  these  were  far 
lower  in  alkaloidal  strength  than  was  to  be  expected  from  any  reas- 
onable interpretation  of  the  pharmacopceial  requirements,  if  it  be 
assumed  that  the  manufacturer  would  follow  the  spirit  of  the  Phar- 
macopoeia by  upholding  the  strength  there  indicated  indirectly,  even 
if  it  was  found  impracticable  to  follow  it  in  the  letter,  in  the  substi- 
tution of  extract  of  Scopolia  root,  rubber,  resins,  etc.,  for  the  offi- 
cinal ingredients.  As  the  officinal  plaster  is  intended  to  be  equal 
in  strength  to  its  own  weight  of  belladonna  leaf,  and  the  average 
alkaloidal  strength  of  this  is  03  or  0  4  per  cent.,  a  plaster  contain- 
ing at  least  0-3  per  cent,  might  be  insisted  upon.  Since  the  publi- 
cation of  the  paper  referred  to,  the  writer  has  had  occasion  to  assay 
two  additional  samples  of  commercial  plasters,  and  found  them  to 
approach  more  closely  to  this  standard  than  the  greater  part  of  those 
previously  examined.  They  contained,  respectively,  0-29  and  0  31 
per  cent,  of  alkaloids.  They  cannot  be  classed  as  officinal,  how- 
ever, since  they  are  not  made  in  accordance  with  the  directions  of 
the  Pharmacopoeia,  but  contain  extract  of  the  root  (belladonna  or 
scopolia)  and  rubber. 
305  Cherry  Street,  Philadelphia. 
BELLADONNA  PLASTERS. 
By  Carl  E.  Smith. 
