OLEAGINOUS  MATTER  FROM  IRON. 
75 
Academy  of  Sciences  of  Paris,  I  thought  it  better  to  bring 
forward  what  I  have  determined  up  to  the  present  time.  M. 
Chevreul  stated  that  the  combination  of  the  iron  with  the  hydro- 
gen seemed  difficult  to  admit,  and  that  this  consideration  had 
led  him  to  conjecture  that  the  water  might  assist  in  the  produc- 
duction  of  the  oily  matter.  He,  moreover,  considered  that  the 
researches  of  M.  Fremy*  on  cast  iron  and  steel,  seemed  to  throw 
some  light  on  the  subject,  by  indicating  that  it  is  not  carbon,  as 
was  represented,  which  yields  the  oily  body.  Now,  we  can 
clearly  gather  from  this,  that  M.  Chevreul  points  to  nitrogen 
as  being,  possibly,  the  principal  constituent  of  the  oil,  and  not 
carbon. 
In  order  to  clear  away  all  doubts  as  to  its  origin,  it  was 
essentially  necessary  to  answer  the  three  following  proposi- 
tions : — 
1.  Is  the  oleaginous  body  produced  during  the  solution  of 
pwe  iron  in  dilute  acids  ? 
2.  Does  iron,  free  from  every  other  impurity  but  carbon, 
yield  the  oil  when  treated  with  acids  ? 
3.  Will  iron,  containing  nothing  but  nitrogen,  furnish  the  oily 
matter  on  similar  treatment  ? 
It  will  be  seen  at  a  glance,  that  the  careful  solution  of  these 
propositions  would  be  certain  to  make  us  acquainted  with  the 
circumstances  which  influence  its  production. 
The  following  are  the  methods  which  I  adopted  for  answering 
each  question  : — 
1.  My  first  object  was  to  prepare  absolutely  pure  iron.  This 
I  procured  by  the  process  generally  employed  for  preparing 
"fer  reduit"  care  being  taken  to  preclude  any  possible  chance 
of  impurity.  The  peroxide  being  precipitated  from  the  pure 
perchloride  by  ammonia,  after  being  well  washed,  it  was  then 
submitted  to  a  low  red  heat.  Moreover,  the  hydrogen  gas  used 
to  decompose  the  peroxide  was  evolved  from  distilled  zinc  and 
pure  sulphuric  acid.  The  metallic  iron  so  procured,  when  dis- 
solved in  dilute  acid,  did  not  yield  the  slightest  trace  of  the  oil. 
I  did  not  come  to  this  conclusion  after  one  or  two  experiments 
alone,  but  after  repeated  trials.    This  overthrows  at  once  the 
*See  Chemical  News,  vol.  iii.  p.  332. 
