546     PRODUCTION  OF  VALUABLE  MANURE  FROM  THE  AIR. 
isocajeputene  passes  ;  like  the  former  it  is  insoluble  in  alcohol, 
but  soluble  in  all  proportions  in  ether  and  oil  of  turpentine. 
Paracajeputene  comes  over  about  316®  ;  it  is  a  viscid  fluid 
of  a  lemon-yellow  color,  slightly  fluorescent ;  unlike  the  two  for- 
mer, it  is  insoluble  in  turpentine;  in  the  air  it  soon  changes  to 
a  red  resin. 
Iodine  acts  on  these  hydrocarbons  when  heated,  and  hydrogen 
is  evolved.  Bromine  thickens  cajeputene  and  isocajeputene, 
which  are  converted  into  a  friable  resin  by  a  mixture  of  sul- 
phuric and  nitric  acids.  Hydrochloric  acid  colors  all  three 
violet,  but  does  not  form  a  definite  compound  with  them.  When, 
however,  oil  of  cajeput  is  shaken  with  hydrochloric  acid  an  un- 
stable compound  02^11^^+  2HC1  is  formed,  which  heated  to  160® 
parts  with  one  equivalent  of  the  acid. 
Bichloride  of  cajeputene  is  formed  when  a  current  of  chlorine 
is  passed  through  a  solution  of  cajeputene  in  nitric  acid.  It  is 
a  heavy  crystallizable  oil  with  an  agreeable  smell ;  it  decomposes 
on  distillation,  and  detonates  with  nitrate  of  silver. 
The  author  has  also  obtained  a  bromide,  G^qHiq  +4Br.  and  a 
hydriodate,  CgoHjg-j- HI. — London  Chem.  JVeivs,  Aug.  31,  1861. 
PRODUCTION  OF  VALUABLE  MANURE  FROM  THE  AIR. 
By  mm.  Margueritte  and  De  Sourdeval. 
The  value  of  guano  and  most  other  concentrated  manures 
consists  to  a  considerable  extent  of  the  ammonia  which  they 
contain.  As  three-quarters  of  the  atmospheric  air  consists  of 
nitrogen,  and  as  hydrogen  forms  one-ninth  of  all  pure  water,  if 
some  cheap  means  could  be  found  for  inducing  the  hydrogen  of 
water  to  enter  into  combination  with  the  nitrogen  of  the  air  in 
the  form  of  ammonia,  this  valuable  manure  could  be  produced 
in  unlimited  quantities,  and  the  agricultural  products  of  the 
world  enormously  increased.  The  efforts  to  do  this  have  been, 
at  last,  crowned  with  success,  as  will  be  seen  by  the  following 
abstract  of  some  recent  continental  researches. 
Since  the  remarkable  labors  of  Messrs.  Liebig,  Schaltenmann, 
and  Kuhlmann,  on  the  fertilizing  action  of  ammoniacal  salts, 
the  production  of  ammonia  at  a  low  price  has  become  a  problem 
