carbonated hydrogenous Gas. 409 
Carbonic acid gas, according to the discovery of M. Monge,* 
undergoes, when submitted to the electric shock, a change si- 
milar to that effected on the carbonated hydrogen; and the 
expansion has been shewn, by Messrs. Landriani and Van 
MARUM,-f to be owing to the same cause, viz. the extrication 
of light inflammable air. The added gas, M. Monge ably con- 
tends, cannot proceed from any other source than the water 
held in solution by all aeriform bodies, the oxygen of which he 
supposes to combine with the mercury. That the decomponent 
of the water, however, in the experiments which I have described, 
is not a metallic body, will appear highly probable when we re- 
flect that there is present in them a combustible substance, viz. 
eharcoal, which attracts oxygen much more strongly than me- 
tals; and the following experiments evince that the mercury, 
by which the air was confined, had no share in producing the 
phaenomena. 
Experiment 9. A portion of carbonated hydrogenous gas 
was introduced into a glass tube- closed at one end, into which 
a piece of gold wire was inserted that projected both within and 
without the cavity of the tube. The open end of the tube was 
then closed by a stopper perforated also with gold wire, so that 
electric shocks could be passed through the confined air, with- 
out the contact of any metal that has the power of decomposing 
water. On opening the tube with its mouth downwards, under 
water, a quantity of air immediately rushed out. 
Experiment 10. The dilatation of the gas was found to pro- 
ceed very rapidly when standing over water, and exposed to 
the action of the electric fluid, conveyed by gold conductors. 
We have only, therefore, in the two preceding experiments, 
* 29 Journal de Physique , 277. f 2 Annales di Chimie, 273. 
