270     Characteristic  Properties  of  Common  Oils.  {Amj\5Ji,  wSJ*"" 
tic  potash,  gives  no  precipitate,  the  creasote  forming  oxalic  acid. 
Carbolic  acid,  when  treated  in  the  same  manner,  is  very  violently 
acted  on  by  nitric  acid  and  forms  picric  aeid  (trinitro-phenylic  acid) 
which,  when  neutralized  with  solution  of  potassa,  gives  a  "  yellow 
crystalline  "  precipitate.  1  part  of  carbolic  acid  in  50  parts  creasote 
can  be  readily  detected  in  this  way. — Can.  Pharm.  Journal,  May%. 
1873. 
ON  THE  CHARACTERISTIC  PROPERTIES  OF  THE  COMMON 
OILS. 
By  M.  G.  Glosssner. 
After  having  reviewed  the  characters  of  the  various  fatty  non-dry- 
ing oils  (olive,  almond,  rape,  sesame,  palm),  and  of  the  drying  (lin- 
seed, poppy,  castor),  the  author  tabulates  the  properties  by  which 
they  may  be  recognized. 
Action  of  Potassa  in  the  Cold. — We  agitate  5  volumes  of  the  oil  with 
1  volume  of  potassa  of  sp.  gr.  1*34.    The  mixture  is: — 
White — almond,  rape  (best),  bleached  olive. 
Yellowish — Poppy,  olive,  rape,  sesame. 
Greenish — Linseed,  hemp.    Oils  containing  copper,  or  artificial- 
ly colored. 
Rose — Rape  (refined). 
Brown  and  compact — Hemp. 
Yellow-brown  and  liquid — Linseed. 
Red— Whale. 
The  oil  is  poured  in  a  test-tube  upon  an  equal  measure  of  fuming 
nitric  acid.  There  appears  at  the  surface  of  separation  a  narrow 
transparent  green  zone — Almond. 
Deep  green,  with  a  rosy  halo  at  top — Poppy. 
Clear  blue-green — Olive. 
Reddish-brown — Linseed.    After  some  time  the  coloration  ex- 
tends to  all  the  oil. 
Green  and  red  at  the  upper  part — Rape. 
Action  of  Concentrated  Sulphuric  Acid  (10  drops  of  oil  to  2  of  acid). 
Color  at  the  surface  of  separation  : — 
Fine  green,  with  brown  stripes — Rape. 
Yellow,  passing  into  olive-green  when  stirred — Poppy  (Media- 
sativa). 
Red  stripes,  shading  into  black — Whale. 
