216  DECOMPOSITION  OF  OXALIC  ACID  BY  LIGHT. 
The  water  of  this  refrigerating  condenser  becoming  very  acid 
by  the  absorption  of  the  excess  of  hydrochloric  gas,  is  utilised 
by  putting  into  it  the  calcined  bones,  where  they  are  dissolved 
or  softened,  rendering  pulverisation  unnecessary. 
The  magma  resulting  from  this  maceration  is  mixed  with  car- 
bon, and  the  whole  evaporated  to  dryness  before  put  into  the 
cylinders. 
Hydrochloric  gas  is  produced  by  the  decomposition  of  sea- 
salt  by  sulphuric  acid.  The  chloride  of  calcium  forming  the 
residuum  in  the  cylinders  can  also  be  utilised  by  treating  it  with 
sulphuric  acid,  which  regenerates  the  hydrochloric  gas,  whilst 
the  lime  is  converted  into  sulphate  of  lime,  which  is  useful  for 
manure.  Chloride  of  calcium  can  also  be  decomposed  by  aqueous 
vapor. — Chem.  News,  London,  July  26,  1862,  from  Moniteur 
Scientifique. 
ON  THE  DECOMPOSITION  OF  OXALIC  ACID  BY  LIGHT. 
By  M.  W.  Seekamp. 
A  solution  containing  5  per  cent,  of  oxalic  acid  and  1  per 
cent,  of  uranic  nitrate  does  not  decompose  in  the  dark  even  at 
100°  C. ;  but  on  being  exposed  to  the  light,  it  disengages  a  gas 
containing  from  56  to  57  per  cent,  of  carbon.  At  the  same 
time  a  slightly  soluble  green  powder  of  uranous  oxalate  is  pre- 
cipitated. This  precipitate  is  composed  of  microscopical,  pris- 
matic, square-based  crystals,  apparently  identical  with  the  pro- 
duct obtained  by  M.  Peligot  in  precipitating  chloride  of  uranium 
by  oxalic  acid.  A  little  formic  acid  is  at  the  same  time  pro- 
duced by  the  combination  of  nascent  oxide  of  carbon  with  water. 
C^|o2=C02+CO+H20. 
Oxalic  acid. 
(UrC20)2 }  °2+2C2HA  =  2  {  °^  }  02+2C02+2H20 
Uranic  oxalate.  Uranous  oxalate. 
Succinic  acid  is  also  decomposed  under  the  influence  of  light ; 
but  this  subject  will  be  treated  separately. — Chem.  News,  London, 
July  26,  1862. 
