﻿CoMMISSIOIs'ER 
  OF 
  AGRICULTURE. 
  465 
  

  

  of 
  more 
  than 
  a 
  very 
  small 
  quantity 
  of 
  turpentine, 
  benzine, 
  rosin, 
  

   or 
  rosin 
  oil, 
  is 
  assured. 
  The 
  process 
  can 
  be 
  carried 
  out 
  in 
  the 
  

   time 
  nec^ssaiy 
  for 
  weig'hing 
  and 
  titrations, 
  as 
  the 
  standard 
  solu- 
  

   tion, 
  unlike 
  the 
  Hubl 
  solution, 
  does 
  not 
  deteriorate 
  on 
  keeping, 
  if 
  

   tightly 
  closed, 
  so 
  that 
  it 
  is 
  always 
  ready 
  for 
  immediate 
  use, 
  and 
  

   there 
  is 
  no 
  waiting 
  for 
  some 
  hours 
  for 
  the 
  reagents 
  to 
  act 
  upon 
  the 
  

   oil, 
  as 
  in 
  the 
  Hubl 
  process, 
  for 
  in 
  this 
  case 
  the 
  reaction 
  takes 
  place 
  

   immediately. 
  

  

  It 
  will 
  be 
  seen 
  from 
  the 
  table 
  of 
  results 
  that 
  the 
  Bromine 
  Addi- 
  

   tion 
  figure 
  of 
  linseed 
  oil 
  lies 
  ordinarily 
  between 
  100 
  and 
  110. 
  

   The 
  low 
  figures 
  of 
  N^o. 
  1 
  and 
  I^o. 
  2 
  are 
  to 
  be 
  accounted 
  for 
  by 
  

   the 
  fact 
  that 
  the 
  samples 
  are 
  several 
  years 
  old, 
  and 
  it 
  is 
  well 
  

   known 
  that 
  keeping 
  lowers 
  the 
  halogen 
  figures 
  of 
  linseed 
  oil. 
  

  

  A 
  low 
  Addition 
  Figure 
  may 
  also 
  be 
  caused 
  by 
  the 
  presence 
  of 
  

   rosin, 
  ix)sin 
  oil, 
  benzine 
  or 
  mineral 
  oils, 
  which 
  have 
  figures 
  usually 
  

   below 
  15; 
  by 
  the 
  presence 
  of 
  some 
  other 
  seed 
  oil, 
  the 
  commonest 
  

   of 
  this 
  class 
  being 
  com 
  and 
  cottonseed 
  oils, 
  having 
  figures 
  in 
  the 
  

   neighborhood 
  of 
  73 
  and 
  63, 
  respectively; 
  or 
  by 
  the 
  oil, 
  in 
  case 
  it 
  is 
  

   a 
  boiled 
  oil, 
  having 
  been 
  boiled 
  in 
  the 
  old-fashioned 
  way 
  at 
  a 
  high 
  

   temperature. 
  

  

  If 
  the 
  Addition 
  Figure 
  is 
  very 
  much 
  higher 
  than 
  110, 
  it 
  will 
  

   be 
  found 
  that 
  the 
  oil 
  contains 
  turpentine, 
  as 
  all 
  other 
  foreign 
  ma- 
  

   terials 
  added 
  have 
  lower 
  figui'es 
  than 
  linseed 
  oil. 
  

  

  The 
  Bromine 
  Substitution 
  Figure 
  of 
  genuine 
  linseed 
  oil 
  is 
  com- 
  

   monly 
  about 
  3. 
  A 
  much 
  higher 
  figure 
  would 
  point 
  to 
  turpentine, 
  

   rosin, 
  or 
  rosin 
  oil, 
  which 
  give 
  figures 
  from 
  20 
  to 
  90; 
  to 
  the 
  

   presence 
  of 
  some 
  petroleum 
  product, 
  benzine 
  having 
  a 
  figure 
  

   in 
  the 
  neighborhood 
  of 
  15, 
  or 
  a 
  heavier 
  petroleum 
  oil, 
  which 
  may 
  

   have 
  as 
  low 
  a 
  figure 
  as 
  linseed, 
  or 
  may 
  be 
  much 
  higher; 
  or 
  to 
  the 
  

   presence 
  of 
  mineral 
  acid 
  in 
  the 
  oil, 
  which 
  may 
  be 
  allowed 
  for 
  by 
  a 
  

   separate 
  determination 
  of 
  its 
  amount, 
  as 
  described 
  under 
  the 
  deter- 
  

   mination 
  of 
  the 
  Acid 
  Figure. 
  

  

  The 
  Hubl 
  figure 
  of 
  raw 
  linseed 
  oil 
  is 
  given 
  by 
  Benedikt 
  from 
  

   148.8 
  to 
  183.4. 
  Boiled 
  oil, 
  according 
  to 
  the 
  same 
  author, 
  may 
  

  

  30 
  

  

  