﻿Commissioner 
  of 
  Agriculture. 
  469 
  

  

  is 
  then 
  returned 
  to 
  the 
  separator 
  and 
  extraoted 
  with 
  another 
  50 
  c. 
  c. 
  

   of 
  ether 
  in 
  the 
  same 
  wav. 
  Tlie 
  combined 
  ethereal 
  solutions 
  are 
  

   evaporated 
  on 
  the 
  water 
  bath, 
  and 
  when 
  the 
  ether 
  has 
  been 
  com- 
  

   pletelj 
  removed 
  the 
  flask 
  now 
  containing 
  the 
  unsaponifiable 
  mat- 
  

   ter 
  is 
  weighed. 
  If 
  the 
  percentage 
  of 
  unsaponifiable 
  matter 
  found 
  

   is 
  large, 
  it 
  may 
  be 
  advisable 
  to 
  repeat 
  the 
  process 
  of 
  saponification 
  

   and 
  extraction 
  upon 
  the 
  unsaponifiable 
  matter, 
  in 
  order 
  to 
  be 
  quite 
  

   certain 
  that 
  no 
  misaponifiable 
  oil 
  has 
  escaped 
  the 
  action 
  of 
  the 
  

   alkali. 
  

  

  The 
  mineral 
  oil 
  may 
  be 
  separated 
  from 
  the 
  rosin 
  oil 
  in 
  the 
  un- 
  

   saponifiable 
  material 
  found 
  in 
  the 
  saponification 
  process 
  by 
  the 
  

   method 
  suggested 
  by 
  the 
  author 
  in 
  the 
  Jour, 
  Amer. 
  Chem. 
  Soc., 
  16, 
  

   385. 
  

  

  Fifty 
  c. 
  c. 
  of 
  nitric 
  acid 
  of 
  1.2 
  sp. 
  gT. 
  are 
  heated 
  to 
  boiling 
  in 
  a 
  

   flask 
  of 
  700 
  c. 
  c. 
  capacity. 
  The 
  source 
  of 
  heat 
  is 
  removed, 
  and 
  

   five 
  gi-ams 
  of 
  the 
  oil 
  to 
  be 
  analyzed 
  added. 
  Tbe 
  flask 
  is 
  then 
  

   heated 
  on 
  the 
  water 
  bath, 
  with 
  frequent 
  shaking, 
  for 
  fifteen 
  to 
  

   twenty 
  minutes, 
  and 
  about 
  400 
  c. 
  c. 
  of 
  cold 
  water 
  added. 
  After 
  

   the 
  liquid 
  has 
  become 
  entirely 
  cold, 
  50 
  c. 
  c. 
  of 
  jjetroleum 
  ether 
  

   are 
  added 
  and 
  the 
  flask 
  is 
  agitated. 
  The 
  oil 
  which 
  remains 
  un- 
  

   acted 
  upon 
  dissolves 
  in 
  tlie 
  ether, 
  while 
  the 
  resin 
  remains 
  in 
  sus- 
  

   pension. 
  The 
  liquid 
  is 
  poured 
  into 
  a 
  tapped 
  separator, 
  leaving 
  

   the 
  lumps 
  of 
  solid 
  resin 
  as 
  far 
  as 
  possible 
  behind 
  in 
  the 
  flask. 
  After 
  

   settling, 
  the 
  aqueous 
  liquid 
  is 
  drawn 
  off 
  and 
  the 
  ethereal 
  layer 
  

   poured 
  into 
  a 
  tarred 
  flask. 
  Another 
  portion 
  of 
  petroleum 
  ether 
  

   is 
  added 
  to 
  the 
  resin 
  remaining 
  in 
  the 
  flask, 
  and 
  allowed 
  to 
  act 
  

   upon 
  it 
  for 
  about 
  ten 
  minutes, 
  when 
  it 
  is 
  added 
  to 
  that 
  in 
  the 
  tarred 
  

   flask. 
  After 
  distilling 
  off 
  the 
  ether, 
  the 
  oil 
  is 
  weighed. 
  Mineral 
  

   oils 
  lose 
  about 
  ten 
  per 
  cent 
  in 
  this 
  way, 
  and 
  hence 
  the 
  weight 
  of 
  

   oil 
  found 
  must 
  be 
  divided 
  by 
  0.9 
  in 
  order 
  to 
  find 
  the 
  amount 
  pres- 
  

   ent 
  in 
  the 
  sample 
  analyzed. 
  

  

  Allen 
  found 
  mineral 
  oils 
  to 
  lose 
  ten 
  to 
  twelve 
  per 
  cent 
  on 
  

   treatment 
  with 
  nitric 
  acid. 
  (Pharm. 
  Jour., 
  3 
  series, 
  11, 
  266.) 
  

  

  Rosin 
  oil. 
  though 
  principally 
  composed 
  of 
  hydrocarbons, 
  may 
  

   contain 
  some 
  unchanged 
  rosin 
  which 
  is 
  saponifiable, 
  and 
  oonse- 
  

  

  