io  Oleic  Acid  and  the  Oleates.  {^m^Zl^ 
was  used,  the  efficiency  was  impaired,  and  the  preparation  increased 
proportionately  in  irritant  properties. 
The  oleates  of  zinc,  bismuth  and  iron  were  also  prepared,  of  which, 
however,  only  the  former  has  of  late  come  into  extensive  use  and 
demand,  and  I  subjoin  my  method  of  preparing  an  ointment  which  has 
been  largely  employed  and  met  with  decided  success  in  the  treatment 
of  eczema  and  lupus,  at  the  hands  of  dermatologists. 
R     Oxide  of  zinc,        .  .  .  .  3l 
Oleic  acid,       .  .  .  .  51 
Liquid  cosmolin,     .  .  .  . 
Dissolve  the  zinc  oxide  at  a  moderate  heat  in  the  oleic  acid,  and. 
then  add  the  cosmolin. 
It  will  be  seen  that  the  zinc  oxide  is  contained  therein  in  but  small 
quantities,  in  comparison  to  the  officinal  zinc  ointment,  but  as  the 
action  of  the  oleates — being  solutions  which  are  readily  absorbed  by  the 
skin — is  so  much  more  potent,  the  effect  is  even  more  decided  and 
satisfactory. 
The  oleate  of  bismuth  is  similarly  prepared,  and  the  oleate  of  iron  is 
readily  obtained  by  dissolving  the  ferric  oxide  in  oleic  acid,  or,  where  a 
ferrous  oleate  is  desired,  by  treating  iron  by  hydrogen  with  oleic  acid  in 
presence  of  water,  yielding  in  this  way  preparations  which  are  doubt- 
less destined  to  prove  of  value  in  therapeutics,  but  of  which  I  cannot 
as  yet  report  any  application. 
The  oleates  of  the  alkaloids  are  certainly  intended  to  crowd  many  of 
our  unsightly  and  often  worthless  ointments  out  of  existence,  by  giving 
definite  means  for  dermic  medication,  and  already  is  the  oleate  of  atro- 
pia  used  conjointly  with  the  above-mentioned  eye-salve  of  mercuric 
oleate. 
The  property  of  oleic  acid  to  dissolve  the  oxides  and  alkaloids,  whereas 
it  has  no  irritant  or  corrosive  action  on  organic  tissue,  has  suggested  to 
me  the  practicability  of  the  use  of  the  oleates  for  hypodermic  injec- 
tions, forming  thereby  a  medicine  which  the  physician  has  been  much 
in  quest  of;  and  recent  experiments  in  that  direction  seem  to  establish 
their  absorption  in  this  way,  although  this  subject  needs  still  further 
experimentation  and  observation. 
In  conclusion,  I  would  speak  of  one  very  important  application 
of  oleic  acid,  which  will  certainly  give  it  the  eminent  position  in  phar- 
macy pointed  out  above.     It  is  its  utility  for  the  separation  of  the 
