116 British Association for the Advancement of Science. 
up the chimney. When carburetted hydrogen passes in, the fact 
is discovered by numerous small explosions, and the whole glass 
work is thrown into vibrations which emit a loud and shrill sound, 
audible at a great distance. 
On a small Voltaic battery of extraordinary energy by W. R. 
Grove, Esq. In a letter published in the Philos. Mag. Feb. 
1839, I stated, (said the author,) some reasons for hoping that by 
changes in the constituents of voltaic combinations of four ele- 
ments, we might greatly increase their energy. . At that period I 
sought in vain for improvements, which a fair induction convin- 
ced me were attainable; but being in the country, all my experi- 
ments were with copper as a negative metal. I was constantly 
_ unable to use concentrated nitric acid as an electrolyte, and its 
importance never occurred to me until forced upon my notice by 
an experiment which I made at Paris for a different object. This 
was an endeavor to prove the dissolution of gold in nitro-muriatie 
acid to be an electrical phenomenon ; or rather, that this (and, as 
I believe with Sir H. Davy, every other chemical phenomenon, ) 
could be resolved into an electrical one by operating on masses 
instead of molecules. 'The experiment was this: the extremities 
of two strips of gold leaf were immersed, the one in nitric, the 
other in muriatic acid ; contact between the liquids being permit 
ted, but mixture prevented, by an interposed porous diaphragm. 
In this case, the gold remained undissolved for an indefinite period, 
but the circuit being completed by metallic contact, either medi- 
ate or immediate, the strip of gold in the muriatic acid was in- 
stantly dissolved. 'Thus, “it seems, that the affinity of gold for 
chlorine is not able alone to decompose muriatic acid; but when 
it is aided by that of oxygen for hydrogen, the decomposition 1s 
effected. The phenomenon bears much analogy to ordinary 
cases of double decomposition. 'The two gold strips in the ex 
periment being connected with a galvanometer, occasioned @ 
considerable deflexion ; and it now occurred to me, coupling this 
experiment with my previous observations, that these same liquids, 
with the substitution of zinc and platinum for the gold leaf, would 
produce a combination of surpassing energy. My expectations 
were fully realized ; and on the 15th of April, M. Becquerel pre- 
sented to the fasieate a small battery of my construction, consist- 
ing of seven liqueur glasses, containing the bowls of common 
aie ise metals zinc and platinum, and the electrolytes 
2 
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