MR. GROVE ON THE GAS VOLTAIC BATTERY. 
107 
however, removed when the gases are in a state of such intimate admixture that it is not 
requisite to convey the action through a chain of particles ; in the gas battery this 
chain is supplied by the intervening electrolyte, and thus the same action which is 
local in the experiments of Dobereiner is circulating in the gas battery; the latter 
bears the same relation to the former as the action of the ordinary voltaic battery 
does to the normal phenomena of chemical affinity. This relation is confirmed by 
the facts detailed in the paper of Dr. Henry, as the gases which he there found would 
combine by the presence of spongy platinum, are precisely those which will combine 
in the gas battery; thus oxygen and hydrogen combine rapidly, oxygen and carbonic 
oxide much more slowly, and oxygen and olefiant gas very feebly, so much so, as, in 
Henry’s experiments, to require heat to induce combination. Of course chlorine and 
hydrogen, which will unite without platinum, will, a fortiori , unite with the aid of 
platinum, or they may in the gas battery occasion secondary action ; the oxygen 
evolved by the decomposition of water by the chlorine combining with the free hy- 
drogen in the tube. As oxygen and ammonia will, when at a slightly elevated tem- 
perature, combine by the influence of spongy platinum, forming water and leaving 
nitrogen, I now in order further to test this relation, tried 
Experiment 26. — Ten cells of the gas battery were charged with oxygen and solu- 
tion of ammonia, with a little sulphate of ammonia added to improve its conducting 
power. This arrangement produced a moderate effect upon the iodide, which was 
continuous ; the liquid rose slowly but uniformly in the oxygen tubes ; a gas was 
evolved in the alternate tubes, which proved to be pure nitrogen. After three weeks 
closed circuit, the gases collected, measured, and averaged gave for each tube, 
Nitrogen evolved = 0 - 07 cubic inch. 
Oxygen absorbed = 0T2 cubic inch. 
Experiment 27. — To examine whether the alkaline character of ammonia had any 
thing to do with the effect, ten cells were charged with oxygen and solution of caustic 
potash, but produced no effect. 
These experiments are strongly corroborative, and seem to me conclusive as to the 
relation between the action of the gas battery and catalysis by spongy platinum. 
Experiment 26 is also remarkable in regard to the binary theory of electrolysis, but 
upon this point I will not here enter. 
Applying the hypothesis of Grotthus to the gas battery, we may suppose that 
when the circuit is completed, at each point of contact of oxygen, water and plati- 
tinum, in the oxygen tube, a molecule of hydrogen leaves its associated molecule of 
oxygen to unite with one of the free gas ; the oxygen thus thrown off unites with the 
hydrogen of the adjoining molecule of water ; and so on until the last molecule of 
oxygen unites with a molecule of the free hydrogen ; or we may conversely assume 
that the action commences in the hydrogen tube. In all these cases we should ever 
bear in mind that we proceed by steps which nature, as hitherto tested by experi- 
ment, has not recognised. All we can safely predicate of the actions at anode and 
MDCCCXLIII. Q 
