Adulteration  oj  Gave  Oil.  25 
which,  in  fact,  are  nothing  but  lead  chamber  crystals.  This  reaction 
treated  analytically  may  some  day  throw  new  light  on  the  formation 
and  composition  of  lead  chamber  crystals. 
The  bisulphide  of  carbon  cleaned  by  means  of  fuming  nitric  acid 
is  the  only  chemically  pure  I  came  across,  and  I  therefore  proceeded 
to  determine  its  specific  gravity  as  well  as  boiling  point,  without  find- 
ing though  any  differences  from  any  former  determinations. 
The  specific  gravity  at  +15'2°C  is  1,266,  and  the  boiling  point 
-j-47-4°C,  at  0-760m  pressure. 
The  pure  bisulphide  shows  materially  no  other  so-called  physical 
properties  than  those  known  heretofore. 
Finally  I  want  to  state,  that  in  treating  raw  bisulphide  of  carbon^, 
coming  from  the  retorts  of  manufacture,  with  fuming  nitric  acid,  I 
could  invariably  detect  mononitrobenzol  in  the  rsidue  of  evaporation, 
which  leads  me  to  believe  that  amongst  the  numerous  products  formed 
in  the  red  hot  retorts,  particularly  if  the  charcoal  was  not  dry  enough, 
there  is  also  benzol. 
2.  The  purifying  influence  of  a  non-colored  and  inodorous  fat,  for 
instance  such  as  the  oil  of  African  palm  kernels,  good  as  it  is  for  the 
bisulphide  of  carbon,  becomes  a  nuisance  when  this  latter  is  used  as  a 
means  of  extraction  of  the  former.  I  advise,  therefore,  from  long 
experience,  all  those  who  extract  fats  (particularly  if  it  is  for  manu- 
facturing) by  means  of  CS2  never  to  use  an  excess  of  this  latter,  and 
never  to  let  a  new  mixture  of  oil  and  bisulphide  run  into  the  still  in 
which  oil  already  freed  from  bisulphide  is  retained.  This  latter  will 
else  be  rendered  impure. — Jour.  Amer.  Chem.  Soc,  November,  1882. 
THE  ADULTERATION  OF  OLIVE  OIL. 
By  Ch.  Marie. 
The  oils  which  are  commonly  used  to  adulterate  olive  oil  are  very 
few  in  number.  Among  the  most  importont  are  the  colza^  oil,  sesame 
oil,  cottonseed  oil,  and  peanut  oil. 
1.  Colza  Oil. — Independent  of  the  conventional  methods  known,  the 
presence  of  this  fraudulent  admixture  may  be  easily  detected  by  means 
of  the  sulphur  contained  in  the  cruciferous  seeds  which  must  be  offered 
as  evidence.  For  this  purpose,  ten  grams  of  the  oil  to  be  tested  are 
saponified  in  a  glass  capsule,  by  means  of  an  alcoholic  solution  of  potas- 
sium hydrate  (caustic  potash)  freed  from  hydrogen  sulphide.  The 
