[M‘a1LL] OXIDATION OF FERROUS CHLORIDE 51 
chlorine in available form, and from 10 to 20 per cent as hydrochloric 
acid. 
Second.—That the oxygen in atmospheric air can be successfully 
employed, although it may be that an impracticably large dilution of 
the resulting chlorine with nitrogen would thereby result.* 
Third.— That very complete dehydration of the charge of ferrous 
chloride is necessary to a high result of free chlorine. 
Fourth.—That both the drying of the charge, and the subsequent 
oxidation are aided by the presence of ferric oxide, which should form 
at least fifty per cent by weight of the charge.’ 
Fifth—That a red heat is necessary to bring about complete 
decomposition. 

* From the equation Fe,01,+30—Fe,0,+2Cl, the ratio of oxygen required 
to chlorine produced is, 1°3 by weight, or 3:4 by volume. Or each gramme of 
chlorine requires nearly 0°25 litre oxygen — 1:25 litres atmospheric air. 
see. wl 1902 94: 
