74 
OLEAGINOUS  MATTER  FROM  IRON. 
If  we  return  now  to  the  historical  recital  of  the  manna  of 
Sinai',  it  is  easy  to  explain  the  use  of  this  substance  as  a  food. 
In  short,  it  is  a  true  honej,  perfected  by  the  presence  of  dex- 
trine. We  see,  at  the  same  time,  that  the  manna  of  SinaT  does 
not  suffice  as  an  aliment,  since  it  does  not  contain  any  nitrogenous 
principle.  Therefore,  animal  food  is  associated  with  it,  as  well 
in  the  actual  usage  of  the  Kurds  as  in  the  biblical  narrative. — 
See  Exodus  xvi.  8 — 13. — London  Pharm.  Journ.,  Nov.,  1861, 
from  Comptes  Rendus. 
ON    THE    OLEAGINOUS    MATTER   FORMED  ON  DISSOLVING 
DIFFERENT  KINDS  OF  IRON  IN  DILUTE  ACIDS. 
By  Emerson  J.  Reynolds. 
Proust,  I  believe,  was  the  first  chemist  who  noticed  that  the 
hydrogen  prepared  by  dissolving  black  cast  iron  in  dilute  sul- 
phuric acid  possessed  a  most  offensive  odor,  and  that  on  being 
passed  through  glass  tubes,  it  caused  them  to  assume  a  greasy 
appearance,  apparently  due  to  the  deposition  of  an  oily  matter, 
which  he  appears  to  have  considered  as  a  combination  of  hydro- 
gen and  iron,  the  non- production  of  which  body,  under  the 
circumstances,  I  will  demonstrate  further  on. 
Berzelius  then  afterwards  noticed  the  formation  of  this  oleagin- 
ous body,  and  gave  it  as  his  opinion  that  it  was  a  compound  of 
carbon  and  hydrogen.  More  recently,  Professor  Cameron  in 
(1855)  made  some  experiments  on  this  oil,  the  results  of  which 
he  communicated  to  the  Chemical  Society  of  Dublin.  He  found 
it  to  be  very  volatile,  and  destitute  of  nitrogen,  and  also  that 
certain  metallic  salts  removed  the  offensive  odor  produced 
by  its  presence. 
But,  after  all,  two  very  important  points  have  been  left 
undetermined,  namely,  the  precise  conditions  under  which  this 
body  is  formed,  and  its  chemical  and  physical  characters  and 
relations. 
Now,  it  is  the  first  of  these  propositions  that  I  intend  dealing 
with  in  the  present  paper,  reserving  the  second  for  a  future  com- 
munication. I  had  contemplated  waiting  until  my  investigations 
were  completed,  before  publishing  the  results ;  but  in  conse- 
quence of  some  observations  made  by  M.  Chevreul,  before  the 
