26    Antimony  Terchloride  as  a  Reagent  for  Oils.  {kuil™l]mk™' 
work  with.  In  passing  I  may  mention  that  I  found  anhydrous  stan- 
nic chloride  completely  soluble  in  benzin ;  the  oil  after  a  time  turns 
reddish-brown  and  is  partially  resinified,  while  large  acicular  crystals 
form  throughout  the  liquid. 
Turning  next  to  antimony  terchloride,  I  attempted  to  use  (Merck's) 
"solution  of  terchloride  of  antimony,  sp.gr.  1-345,"  but  found  this  would 
not  mix  sufficiently  well  with  oils  to  produce  satisfactory  reactions. 
Good  results  were,  however,  obtained  by  concentrating  this  solution 
on  the  water-bath  to  a  syrupy  consistence. 
Antimony  terchloride,  as  thus  prepared,  reacts  with  all  the  oils 
which  I  have  tried,  animal,  vegetable,  essential,  and  those  derived 
from  petroleum.* 
In  the  case  of  the  animal  and  vegetable  oils  there  ensues  generally 
a  rapid  darkening,  the  color  turning  to  a  reddish,  greenish,  or  dirty 
brown,  accompanied  generally  by  a  perceptible  rise  in  temperature, 
and  increased  consistency  of  the  oil,  the  latter  becoming  viscid,  and 
in  one  or  two  cases  solidifying  altogether.  After  the  lapse  of  a 
little  time  a  stratum  of  antimony  chloride  solution  separates  at  the 
bottom  of  the  test  tube,  which  has  a  greenish-yellow  color.  The 
oils  for  which  this  general  description  may  suffice  are  rape  seed, 
poppy  seed,  tallow,  neat's  foot  and  sperm. 
Some  characteristic  reactions  were  observed  with  the  following : 
1.  Olive  oil  (three  samples).  Forms  a  whitish  emulsion,  rapidly 
passing  through  light  to  dark  green.  No  perceptible  rise  of  temper- 
ature. 
2.  Cotton  seed  oil  (two  samples.)  Turns  chocolate  brown,  with 
evolution  of  considerable  heat.  One  of  the  samples  solidified  a  few 
minutes  after  the  test  was  applied,  so  that  the  tube  could  be  inverted, 
while  still  warm,  without  the  oil  flowing  out. 
3.  Neat's  foot  oil.  Turns  pink  ;  subsequently  darker  and  thicker. 
The  temperature  rises. 
4.  Rosin  oil.  Turns  purple.  Though  the  color  becomes  gradually 
darker,  the  peculiar  purple  tint  can  be  recognized  even  after  a  long 
time. 
Of  the  petroleum  oils  I  tried  gasolin,  benzin,  and  kerosene. 
After  shaking,  two  strata  separate  in  the  test-tube.  A  portion  of  the 
oil  is  resinified,  the  resin  adhering  to  the  sides  of  the  tube  a  thin, 
*  The  experiments  were  made  by  putting  2-3  c.  c.  of  the  oil  into  a  test  tube, 
adding  a  few  drops  of  the  reagent,  and  shaking  till  a  mixture  was  effected. 
