AMju]yTm2EM  }    Bam  to  Detect  Adulteration  of  Oils.  811 
periments  on  adulterated  samples  submitted  to  us.  The  test  is  gly- 
cerin, in  which  true  creasote  is  insoluble,  or  nearly  so.  Carbolic  or 
phenic  acid,  on  the  contrary,  dissolves  in  all  proportions,  and  any 
large  amount  of  this  latter  substance,  if  mixed  with  true  creasote, 
will  render  the  creasote  soluble. 
The  danger  of  substituting  carbolic  or  phenic  acid  for  creasote  to 
be  used  internally  for  food  is  well  known. 
To  test  a  suspected  sample,  mix  it  with  an  equal  quantity  of  pure 
glycerin.  If  they  unite  and  make  a  clear  solution,  the  substance  is 
carbolic  acid,  or  in  greater  part  consists  of  it. — Pharm.  Journ., 
Lond.,  May  18,  1872. 
HOW  TO  DETECT  ADULTERATION  OF  OILS. 
The  following  instructions  for  the  detection  of  adulterated  linseed 
and  refined  rape  oils,  drawn  up  by  Messrs.  Blundell,  Spence  &  Co., 
may  prove  very  useful  to  many  of  our  readers  who  wish  to  possess 
either  article  perfectly  genuine  : — 
"  Rosin  oil  is  exceedingly  heavy,  having  a  sp.  gr.  of  0*989  (the 
gravity  of  pure  linseed  oil  is  about  0*935).  Fischer's  oil  balance  is 
a  convenient  instrument  for  comparing  the  density  of  oils.  The  fol- 
lowing table  shows  the  results  of  a  few  experiments  : — 
Fischer's    Gay-Lussac's  Sp. 
oil  balance,    alcoholora'r.  gr. 
Pure  linseed  oil,  29°  to  30°       50°  0-935 
Linseed  oil  containing  5  p.  c.  rosin  oil,  27°  to  28°       49°  0*939 
"      10       «       "     25°  to  26°       47J°  0*943 
"  "      20       "       "     23°  to  24°       46°  0*947 
Rosin  oil,  —  6°  0*989 
If  the  sample  of  oil  is  below  29°,  the  presence  of  rosin  oil  may  fairly 
be  suspected,  and  the  following  confirmatory  tests  should  be  applied  : 
: — Put  about  a  quarter  of  an  ounce  of  the  suspected  sample  into  an 
ounce  vial,  and  add  pure  linseed  oil  till  it  is  about  three-quarters  full. 
If  the  sample  under  examination  contains  rosin  oil,  the  pure  linseed 
last  added  floats  on  the  top,  the  line  of  contact  being  plainly  visible. 
If  the  finger  be  now  placed  on  the  mouth  of  the  bottle,  and  the  latter 
inverted  two  or  three  times,  and  held  up  to  the  light,  bright  wavy 
streaks  will  be  observed,  caused  by  the  slow  mixing  of  the  twTo  oils. 
Even  five  per  cent,  of  rosin  oil  may  easily  be  detected  in  this  way. 
Place  a  slab  of  clean  glass  on  a  piece  of  white  paper,  at  one  end  put 
