598 
Oleates. 
Am.  Jour.  Pbarm 
Dec.  1889. 
being  mixed  and  boiled  until  the  resulting  oleate  furnished  a  mass. 
The  long  boiling  always  resulted  in  a  partial  decomposition  of  the 
oleate,  more  or  less  of  the  mercury  being  reduced.  H.  B.  Parsons 
(loc.  cit.)  proposed  the  decomposition  of  potassium  oleate  by  means  of 
a  solution  of  mercuric  nitrate.  Mr.  Louis  Dohme  (Amer.  Jour. 
Phar.,  1873,  p.  158)  proposed  a  similar  formula.  With  proper  care 
this  method  will  yield  good  results.  The  following  is  the  formula  I 
have  used : 
Take  of— 
Oleic  acid  1.000  grains. 
Potassa   220      "     or  q.  s. 
Red  oxide  of  mercury     383  " 
Mtricacid   323      "     or  q.  s. 
Alcohol   6  fluidrachms. 
Water,  a  sufficient  quantity. 
Saponify  the  oleic  acid  with  the  potassa  as  directed  in  the  formula 
for  zinc  oleate,  and  dissolve  the  resulting  soap  in  two  pints  of  warm 
water  and  filter.  Mix  the  nitric  acid  with  the  two  fluidounces  of  water, 
heat  to  boiling  and  add  the  mercuric  oxide  previously  reduced  to 
powder.  Boil  until  it  is  entirely  dissolved,  adding,  if  necessary,  a  few 
drops  of  nitric  acid  additional.  Dilute  the  solution  of  mercuric 
nitrate  with  four  fluidounces  of  water.  Warm  both  solutions  to66°C. 
(150°F.)  and  add  the  oleate  of  potassium  solution  to  the  mercury 
solution,  stirring  constantly.  Decant  the  aqueous  solution  and  wash  the 
precipitate  with  warm  water  not  exceeding  150°F.  If  precipitated  at 
a  much  lower  temperature  it  will  be  necessary  to  heat  the  mixture  to 
near  boiling  in  order  to  form  a  mass  of  the  precipitate,  which  heating 
is  almost  certain  to  result  in  a  partial  decomposition  of  the  oleate. 
The  same  is  apt  to  result  if  the  solutions  are  mixed  at  a  higher  tem- 
perature. In  connection  with  this  we  recall  the  experiments  of  Chas. 
Bice,  who  proved  that  as  the  temperature  was  advanced  in  preparing 
oleate  of  mercury  the  quantity  of  oxide  reduced  greatly  increased. 
(Amer.  Jour.  Phar.,  1873,  p.  1). 
The  yield  by  the  above  formula  was  1,329  grains,  theoretical  yield 
being  1,350  grains.  Oleate  of  mercury  as  thus  prepared  is  about  the 
color  of  a  very  pale  citrine  ointment  and  of  somewhat  softer  consistency, 
fuses  at  66°  C.  (150°  F.),  yielding  an  entirely  clear  fluid  at  70°C.  It  is 
very  soluble  in  carbon  bisulphide,  chloroform,  ether  and  turpentine,  and 
yields  an  opalescent  solution  in  benzol  and  petroleum  ether,  and  is 
slightly  soluble  in  absolute  alcohol  and  alcohol. 
