ON  OLEUM  ARACHIS  HYPOG^M. 
295 
A  number  of  efforts  were  made  by  the  use  of  the  nitrate  of 
mercury,  to  discover  adulterations  of  oil  of  sweet  almonds,  or 
olive  oil  with  pea-nut  oil.  It  was  found  that  an  ointment  made 
from  olive  oil  and  lard  became  very  hard,  and  entirely  unfit  for 
use,  and  almond  oil  and  lard  produced  the  same  result.  Oint- 
ments made  from  equal  parts  of  olive  and  nut  oils,  and  in  the 
same  proportions  from  almond  and  nut  oils  without  lard,  formed 
preparations  of  a  dark  green  color,  of  a  medium  consistence  and 
very  lumpy.  Finally,  ointments  were  made  respectively  in  the 
proportions  of  one  part  of  nut  oil  to  seven  of  almond  oil  ;  two 
parts  to  six,  and  three  to  five,  when  it  was  found  that  in  pro- 
portion to  the  amount  of  almond  oil  present,  the  ointment  was 
softer  and  of  a  deeper  color  until  they  reached  equal  parts  ; 
when  the  almond  oil  is  in  excess,  the  ointment  becomes  harder, 
darker,  and  very  lumpy.  Olive  oil  treated  in  the  same  manner 
indicated  similar  results,  so  that  there  would  seem  to  be  no  diffi- 
culty in  detecting  the  adulteration,  if  practiced  to  any  consider- 
able extent.  As  there  are  so  many  circumstances  in  the  prepa- 
ration of  the  ointment  of  the  nitrate  of  mercury,  which  would 
modify  the  result,  such  for  instance  as  the  variation  of  tempera- 
ture, the  mode  of  manipulation,  or  the  amount  operated  upon, 
what  may  have  appeared  as  tests  in  this  case  may  prove  differ- 
ently in  more  experienced  hands.  These  experiments  are  not 
therefore  offered  as  reliable  tests,  but  are  merely  stated  as 
results. 
The  olive  oil  directed  in  the  officinal  process  for  making  lead 
plaster  was  replaced  with  nut  oil,  but  did  not  result  satisfactorily. 
It  was  found  that  while  it  seemed  to  combine  readily  with  the 
litharge,  and  produce  a  uniform  mass,  it  would  not  become  of 
the  proper  degree  of  hardness.  It  was  also  found  not  to  be  a 
drying  oil. 
In  the  arts  it  has  been  found  to  answer  admirably  the  pur- 
poses of  lubrication,  when  the  lighter  kinds  of  machinery  are 
used,  and  one  manufacturer  heard  from,  has  found  it  to  be  quite 
as  applicable  to  shafting  ;  it  is  considered  quite  equal  in  this 
respect  to  the  coal  oil  now  in  such  general  use  for  this  purpose. 
It  possesses  the  advantage  over  most  other  oils  in  being  more 
limpid,  and  consequently  less  liable  to  gum  up  the  machinery. 
In  the  manufacture  of  wool  it  has  also  been  found  to  be  a 
