120  Notes  on  Compound  Re sorcinol  Ointment.  {AnMi?cb,i908.rm' 
In  two  experiments  on  the  rate  of  deterioration  of  preparations  of 
digitalis,  one  fluidextract  lost  in  17^  months  22-6  per  cent,  of  its 
digitoxin,  and  another  fluidextract  in  25  months  lost  15-9  per 
cent.  These  were  preparations  which  came  back  to  the  laboratory 
after  having  been  out  in  the  trade,  and  we  have  no  knowledge  of 
the  conditions  as  to  light,  heat,  etc.,  under  which  they  were  kept 
during  the  time  specified.  These  results  would  indicate,  however, 
that  under  ordinary  trade  conditions  fluidextract  of  digitalis  deterior- 
ates at  the  rate  of  about  1 1  per  cent,  per  year. 
Research  Laboratory  of  the 
H.  K.  Mulford  Company, 
January  7,  1 908. 
NOTES  ON  COMPOUND  RESORCINOL  OINTMENT,  N.F. 
By  E.  Fuu^rton.  Cook,  P.D. 
This  ointment  has  been  the  source  of  considerable  discussion  and 
some  annoyance  on  the  part  of  pharmacists  throughout  the  country, 
owing  to  the  difficulty  which  is  experienced  in  preparing  it  when 
the  N.F.  directions  are  strictly  followed.  Resorcinol  is  described  in 
the  Pharmacopoeia  as  "  colorless  needle-shaped  crystals,"  etc.,  and 
the  paragraph  further  states, "  it  acquires  a  pinkish  tint  on  exposure 
to  light  and  air." 
Until  very  recently  resorcinol,  as  found  in  the  pharmacy,  was  a 
needle-shaped  crystal  corresponding  to  this  description  ;  conse- 
quently, in  preparing  this  ointment,  for  which  there  has  been  con- 
siderable demand,  it  is  necessary  to  finely  powder  the  crystals  in 
order  to  incorporate  them  in  the  wool-fat,  as  directed  in  the  N.F. 
The  experience  has  usually  been  that  it  is  very  difficult  to  obtain 
a  smooth  ointment  at  this  point,  owing  to  the  difficulty  of  powdering 
the  resorcinol.  In  fact,  the  water  has  a  tendency  to  separate  from 
the  wool-fat,  producing  a  spongy  mass.  This  condition  was  experi- 
enced with  an  old  sample  of  hydrous  wool-fat,  a  sample  newly  pur- 
chased, and  with  one  prepared  by  incorporating  30  per  cent,  of  water 
with  anhydrous  wool- fat.  The  difficulty  in  incorporating  resorcinol 
with  the  wool-fat  may  be  overcome  in  one  of  two  ways:  either  by 
obtaining  resorcinol  in  an  impalpable  powder,  which  has  recently 
been  offered  the  trade,  or  by  dissolving  the  crystal  resorcinol  in  the 
