RESEARCHES IN ELECTRO-CHEMISTRY. 215 
dering gold and platina electro-positive, seems to me so extra- 
ordinary and so important a fact with regard to the chemical 
theory of galvanism, that I cannot but recommend it to the 
full attention of philosophers. Why indeed should a piece of 
platina, being surrounded with a film of hydrogen, and vol- 
taically associated with common platina, produce a current 
when plunged into pure water? Which is the chemical action 
that possibly can take place under such circumstances? Ac- 
cording to the present state of our chemical knowledge, it is 
very difficult, if not impossible, to give a satisfactory answer 
to that question. Has perhaps all the hydrogen hitherto pre- 
pared not been chemically pure, and does it always contain a 
principle still more electro-positive than hydrogen itself, that 
is, having a greater affinity for oxygen than hydrogen has? 
Careful experiments alone can decide these important points. 
The fact above stated, that ozone is not developed at the 
positive electrode, unless the latter be either of gold or of pla- 
tina, is, in my opinion, very easily accounted for. These 
metals having, at the common temperature, very little affinity 
for ozone, do not combine with it, any more than they do with 
oxygen in the same circumstances, whilst the other metallic 
bodies readily unite with the odoriferous principle*. 
At a high temperature, gold and platina appear to be capable 
of combining with ozonef ; and this property seems to account 
for the fact, that from heated dilute sulphuric acid, for instance, 
the smelling substance cannot be disengaged. It is, however, 
possible that ozone, in the moment of its being eliminated by 
the current, reacts upon the heated water, combining with the 
hydrogen of the latter. 
The fact that no ozone is set free if the electrolytic fluid 
happens to be mixed with some readily oxidable substance, 
with iron-vitriol, for instance, seems to depend upon a decom- 
position of water, the oxygen of the latter uniting with the 
protoxide of iron, and its hydrogen with ozone. The non- 
appearance of the latter is indeed very easily understood, if we 
suppose its action to be entirely analogous to that of chlorine 
and bromine. 
Before proceeding to the discussion of other facts, I must 
say a few words on the polarizing influence exerted by ozone 
upon gold and platina. In former papers I have endeavoured 
to prove, experimentally, that certain voltaic conditions which 
some metals (placed under given circumstances) seem to assume, 
are not to be considered as real modifications of those metals 
themselves (a view still maintained by some philosophers), but 
* See § 5. t Ibid. 
