AmMay^9Po5arm'}        Ointment  of  Mercuric  Nitrate.  235 
perature."  Its  properties  are  those  of  a  colorless  or  pale-yellow 
oily  liquid,  having  a  slightly  fatty  odor,  a  bland  taste,  etc.  Its 
composition  is  chiefly  olein,  with  variable  quantities  of  palmatin 
and  stearin. 
It  seems,  too,  that  the  proposed  changes  in  the  bases  of  the 
citrine  ointment  have  resulted  from  a  disregard  of  several  important 
facts.  First,  that  we  have  in  lard  oil  a  colorless  or  pale-yellow  sub- 
stance, and  forgetting  that  the  effect  of  nitric  acid  upon  fixed  oils 
depends  not  only  upon  their  composition,  but  also  upon  the  pres- 
ence of  coloring  matter.  In  the  second  place,  the  comparative  sim- 
plicity of  the  product  excluding  as  far  as  possible  complicated  and 
not  thoroughly  understood  reactions.  Third,  that  these  existing 
natural  impurities,  stearin  and  palmatin,  permitted  by  the  United 
States  Pharmacopoeia,  can  be  augmented  to  a  certain  degree,  if  it 
should  be  desired,  without  very  materially  altering  or  introducing 
more  complex  reactions.  Such  a  procedure  as  the  latter  is,  how- 
ever, under  no  circumstances  recommended. 
Many  fats  and  mixtures  of  fats  have  been  proposed  to  replace 
lard  oil,  and  resulting,  perhaps,  in  as  many  failures  to  produce  a  sat- 
isfactory product;  just  what  happens  when  temperature  is  disre- 
garded and  the  thermometer  ignored  in  carrying  out  the  official 
process.  Suffice  it  to  mention  but  a  few :  Olive  oil  and  lard,  lard, 
butter,  lard  oil  and  lard,  etc. 
Not  infrequently  is  there  lodged  complaint  against  the  official 
ointment  that  it  remains  too  soft,  which  may  be  overcome  in  a 
measure  by  the  use  of  a  formula  given  below.  The  proportions1  of 
lard  and  lard  oil  used  by  a  certain  experimenter,  who  found  after 
a  consideration  of  various  fats  and  mixtures  of  fats,  including  the 
one  hinted  at  above,  none  as  satisfactory  as  lard  oil,  a  conclusion  in 
which  we  certainly  concur,  could  not  be  ascertained,  or  they  should 
have  been  used  here  for  a  comparative  study. 
The  official  formula  as  it  would  stand  modified  follows : 
Mercury  70  grammes. 
Nitric  acid  175  " 
I/ard  (anhydrous)  150 
Iyard  oil  610  " 
"  Heat  the  lard  oil,  in  a  glass  or  porcelain  vessel,  to  a  tempera- 
1Reichard,  Am.  Jour.  Pharm.,  Vol.  55,  pp.  438  et  seq. 
