64 
Tincture  of  Cantharides. 
J  Am.  Jour.  Pharm., 
1       Feb.,  1878. 
TINCTURE  OF  CANTHARIDES. 
By  Geo.  W.  Kennedy,  Ph.G. 
The  time  is  fast  approaching  for  the  National  Convention  for  Re- 
vising the  Pharmacopoeia  to  assemble  in  the  city  of  Washington,  D. 
C,  on  the  first  Wednesday  in  May,  1880. 
By  reference  to  the  various  pharmaceutical  journals,  I  notice  that 
committees  have  been  appointed  from  several  of  the  medical  and  phar- 
maceutical colleges  and  associations  for  the  purpose  of  preparing  a  list 
of  drugs  and  chemicals  used  in  their  respective  localities,  and  also  to 
furnish  the  best  working  formulas  for  the  large  number  of  tinctures, 
syrups,  solid  and  fluid  extracts,  and  other  pharmaceutical  preparations 
in  general  use. 
The  time  intervening  before  the  assembling  of  the  final  committee 
is  but  two  years,  and  it  is  absolutely  necessary  for  the  many  workers  to 
commence  the  labor  assigned  them,  at  once.  I  observe  that  many  com- 
mittees have  organized,  and  are  pushing  their  work  forward  favorably. 
Judging  from  the  material  composing  the  committees,  there  is  no  doubt 
but  their  work  will  be  done  well  and  in  a  systematic  order. 
It  is  likewise  the  duty  of  all  pharmacists,  no  matter  whether  serving 
on  committees  or  otherwise,  if  they  have  any  suggestions  or  recom- 
mendations to  make  in  the  direction  of  improvement  of  pharmacopoeia 
processes  or  formulas,  to  report  the  same,  either  to  one  of  the  many 
committees  or  through  some  pharmaceutical  journal. 
The  object  of  the  writer  of  this  article  is  to  recommend  a  change  in 
the  menstruum  used  in  the  preparation  of  tincture  of  Spanish  fly, 
There  is  no  doubt  but  all  pharmacists  are  cognizant  that  diluted  alco- 
hol is  the  menstruum  directed  to  be  used  by  our  present  Pharmacopoeia. 
I  find,  after  experimenting,  that  alcohol  is  preferable  to  diluted  alco- 
hol, for  the  following  reasons  : 
1st,  because  diluted  alcohol  does  not  dissolve  the  cantharidin, 
the  active  and  vesicating  principle  of  the  drug,  so  well  as  alcohol. 
The  writer,  to  satisfy  his  curiosity,  collected  and  preserved  the 
dregs  after  making  several  quantities  of  the  tincture  as  now  pre- 
pared by  the  U.  S.  Pharmacopoeia,  dried  them,  and  in  a  perco- 
lator submitted  them  to  the  action  of  alcohol  until  completely  ex- 
hausted. The  alcoholic  tincture  was  evaporated  on  a  water-bath  to 
about  the  consistence  of  simple  cerate,  a  small  plaster  was  made  and 
applied,  which,  in  the  course  of  an  hour,  produced  redness  of  the  skin, 
