﻿468 
  Sevk.ntii 
  Anmaj. 
  Kepout 
  ok 
  the 
  

  

  ter, 
  for 
  the 
  adulterant 
  can 
  be 
  actually 
  separated 
  from 
  the 
  genuine 
  

   linseed 
  oil 
  and 
  exhibited, 
  whereas, 
  in 
  the 
  case 
  of 
  some 
  other 
  adul- 
  

   terants, 
  the 
  evidence, 
  though 
  it 
  may 
  be 
  conclusive, 
  is 
  of 
  a 
  charac- 
  

   ter 
  requiring 
  more 
  demonstration 
  to 
  one 
  unfamiliar 
  -with 
  tlie 
  scien- 
  

   tific 
  examination 
  of 
  oils. 
  The 
  adulterants 
  -whose 
  presence 
  can 
  in 
  

   this 
  way 
  be 
  demonstrated 
  by 
  actual 
  separation 
  are 
  mineral 
  oil 
  and 
  

   usually 
  rosin 
  oil. 
  Benzine 
  and 
  turpentine, 
  although 
  nnsaiwnifiablc, 
  

   are 
  not 
  found 
  Anth 
  the 
  unsaponifiable 
  matter, 
  as, 
  from 
  the 
  nature 
  

   of 
  the 
  methods 
  of 
  analysis, 
  only 
  materials 
  that 
  are 
  practically 
  non- 
  

   volatile 
  are 
  counted 
  as 
  unsaponifiable. 
  They 
  are 
  easily 
  separated 
  

   and 
  determined, 
  however, 
  as 
  volatile 
  oil. 
  

  

  There 
  are 
  several 
  methods 
  for 
  determining 
  the 
  percentage 
  of 
  

   unsaponifiable 
  material, 
  proposed 
  by 
  different 
  experimenters. 
  Some 
  

   treat 
  the 
  oil 
  with 
  alcoholic 
  or 
  aqueous 
  solution 
  of 
  potash 
  or 
  soda, 
  

   evaporate 
  off 
  the 
  alcohol 
  or 
  water, 
  and 
  treat 
  the 
  dried 
  soap 
  with 
  

   petroleimi, 
  ether 
  or 
  chloroform 
  to 
  dissolve 
  the 
  unsaponifiable 
  por- 
  

   tion. 
  Other 
  experimenters, 
  after 
  saponifying 
  the 
  soap 
  with 
  alco- 
  

   holic 
  solution 
  of 
  potash 
  and 
  evaporating 
  off 
  the 
  alcohol, 
  dissolve 
  the 
  

   resulting 
  soap 
  in 
  water 
  and 
  agitate 
  the 
  solution 
  with 
  ether 
  several 
  

   times 
  to 
  remove 
  from 
  the 
  soap 
  solution 
  the 
  unsaponifiable 
  matter 
  

   which 
  it 
  holds 
  in 
  suspension. 
  

  

  A 
  method 
  which 
  can 
  with 
  safety 
  be 
  recommended 
  for 
  deter- 
  

   mining 
  imsaponifiable 
  matter 
  in 
  linseed 
  oil 
  is 
  substantially 
  that 
  

   described 
  in 
  Allen, 
  Comm. 
  Org. 
  Anal., 
  3d 
  ed.. 
  Vol. 
  2, 
  Part 
  1, 
  p. 
  112. 
  

   A 
  quantity 
  of 
  oil 
  vai-ying 
  from 
  1 
  to 
  10 
  grams, 
  depending 
  upon 
  

   the 
  amount 
  of 
  unsaponifiable 
  matter 
  present, 
  is 
  boiled 
  for 
  two 
  

   hours, 
  with 
  frequent 
  shaking, 
  \Aath 
  excess 
  of 
  alcoholic 
  solution 
  of 
  

   caustic 
  potash, 
  in 
  a 
  flask 
  provided 
  mth 
  a 
  return 
  condenser. 
  . 
  The 
  

   alcohol 
  is 
  then 
  distilled 
  off 
  until 
  only 
  a 
  small 
  quantity 
  remains. 
  

   The 
  soap 
  is 
  then 
  dissolved 
  in 
  w^ater, 
  using 
  75 
  to 
  100 
  c. 
  c. 
  for 
  the 
  

   purpose, 
  transferred 
  to 
  a 
  tapped 
  separator, 
  and 
  50 
  c. 
  c. 
  of 
  ether 
  

   added. 
  The 
  liquids 
  axe 
  then 
  mixed 
  by 
  taking 
  and 
  allowed 
  to 
  

   settle. 
  The 
  aqueous 
  liquid 
  is 
  then 
  drawn 
  off, 
  the 
  ethereal 
  layer 
  

   washed 
  with 
  a 
  few 
  c. 
  c. 
  of 
  water, 
  to 
  which 
  a 
  little 
  caustic 
  potash 
  

   has 
  been 
  added, 
  and 
  poured 
  into 
  a 
  tarred 
  flask. 
  The 
  soap 
  solution 
  

  

  