60 1.8.C. Proceedings of the Ninth [N.S., XVIII, 
order to account for the observed chemical changes. It is 
romarkable that a very large number of such biochemical oxi- 
dations have been imitated in the laboratory by the simple 
process of induced oxidation as already mentioned. We a 
now engaged in further generalising this tvpe of induced oxi- 
dation and in finding out the intermediate products of oxidation 
in these cases. 
It has been shown in a previous paper that the oxidising 
power of hydrogen peroxide is greatly accelerated in presence 
of ferrous and ferric salts, thus if tartaric acid or starch and 
hydrogen peroxide be brought together at the ordinary temper- 
ature hardly any chemical reaction takes place, but as soon as 
a ferrous or a ferric salt is added the oxidation of tartaric acid 
or starch rapidly takes place (Dhar Jour. Chem. Soc. 1917, ITI, 
94). There is a great importance of reactions of this type in 
the explanation of oxidations in the human body. The food 
in the animal body is oxidised by the atmospheric oxygen 
¥: 
food taken up in the body. 
As we have shown in the laboratory, that iron salts (either 
f 
ge ie oxidising power of the peroxide, similarly in 
salts in medicine, the animal body the iron in haemoglobin 
resent in the blood catalytically accelerates 
the oxidation of the food stuff by the peroxide formed in the 
body from the inhaled oxygen. Now when there is deficiency 
of iron in the blood, the animal body suffers from anaemia be- 
cause the amount of catalyst necessary for rapid oxidation falls 
short. At this stage any iron salt taken in the system will 
supply the natural deficiency and the necessary amount of oxi- 
dation will take place. This is the probable mechanism of the 
internal use of iron salts whether ferrous or ferric in medicine. 
It has also been observed that induced oxidation can take 
Negative Cata- ti r hand, a 
iyi an@ indossa OMT conditions. On the othe 
reactions. solution of sodium sulphite is readily oxi- 
dised to sodium sulphate 
_ Now if we mix the two together both the oxidations go on 
simultaneously. At the same time a curious phenomenon 
takes place. The velocity of the oxidation of sodium sulphite 
becomes very small in presence of sodium arsenite, that 
is sodium arsenite which is undergoing a slow oxidation acts as 
a powerful negative catalyst in the exidation of sodium sul- 
phite. Similarly a solution of oxalate which also undergoes 
slow oxidation in presence of sodium sulphite, which is itself 
