183 
combining with it, when it is negatively electrified *, 
In gold and platina, which have a very weak affinity 
for oxygen, even the accumulation of positive electri- 
city is insufficient to effect oxidation; and hence, 
when these metals are employed, the oxygen passes off 
in a gaseous form, like the hydrogen at the opposite 
pole. 
451. The chemical actions, which the Galvanic 
fluid thus exerts, are equally accomplished by the 
operation of common electricity. By the concentra- 
ted discharge of this fluid, iron- wire, and other me- 
tals are speedily reduced to the state of oxides f. 
The formation of water, by the combustion of hy- 
drogen, and the production of nitric acid by the 
electrization of atmospheric air, m the great experi- 
ments of Mr Cavendish, afford, also, pure examples 
of combination. On the other hand, by the varied 
operation of the same agent, the products, thus form- 
ed, may again be decomposed. Thus, M. Beccaria 
revivified many metallic oxides by the agency of e- 
kctricity, restoring the oxide of zinc te its metallic 
form, and reconverting cinnabar into real quicksilver J. 
So, in the experiments of the Dutch chemists, and of 
Dr Pearson, water was resolved into its constituent 
elements, by the agency of the same power ^[ ; and 
nitric acid might, doubtless, be made to undergo a 
similar change, since Dr Wollaston readily decom- 
posed it by Galvanic electricity . Hence, then, the 
* Phil. Trans. 1 807. 
t Priestley's Hist. Elec. p. 2?(). J Ibid. p. < 
5f Murray's Chem. vol. ii. p. 172, 
Phil. Trans, an, 1801, p. 428. 
