Volta, Alessandro. On the electricity
excited by the mere contact of conducting substances of different kinds.
In a letter from Mr. Alexander Volta … to the Rt. Hon. Sir Joseph
Banks … pp. 403-431, extracted from Philosophical Transactions of the
Royal Society of London for the year MDCCC. London: W. Bulmer, 1800.
Quarto, recent wrappers. $3800.
“Volta’s
greatest contribution to science began with the discovery by Luigi
Galvani in 1791 that the muscles in dead frogs contract when two
dissimilar metals (brass and iron) are brought into contact with the
muscle and each other. Volta successfully repeated Galvani’s
experiments using different metals and different animals, and he also
found that placing the two metals on his tongue produced an unpleasant
sensation. The effects were due to electricity and in 1792, Volta
concluded that the source of the electricity was in the junction of the
two metals and not, as Galvani thought, in the animals … In 1796,
Volta set out to measure the electricity produced by different metals,
but to register any deflection on the electrometer he had to increase
the tension by multiplying that given by a single junction. He soon hit
upon the idea of piling discs of metal on top of each other and found
that they had to be separated by a moist conductor to produce a current
… Volta’s discovery was a sensation, for it enabled high electric
currents to be produced for the first time. It was quickly applied to
produce electrolysis, resulting in the discovery of several new chemical
elements, and this led throughout the 1800s to the great discoveries of
electromagnetism and electronics that culminated in the invention of the
electrical machines and electronic devices that we use today” (The
Hutchinson Dictionary of Scientific Biography, Vol. II, p. 941).
“The voltaic pile
revolutionized the theory and practice of electricity, so that within
one hundred years of Volta’s invention more progress was made than in
the two thousand four hundred years between the tentative experiences of
Thales and the publication of Volta’s letter addressed to Sir Joseph
Banks, President of the Royal Society. The pile consisted of a series of
copper and zinc discs separated by pieces of cloth, paper, or
paste-board soaked in a saline or acid fluid. Suitable connexion to an
electroscope showed that (like a frictional machine) the pile produced
an electric charge: but Volta demonstrated also that the action was
continuous where an unbroken circuit permitted the flow of what he
called, in a gracious gesture, the galvanic fluid" (PMM). PMM 255. Text
in French, as issued. With
one folding engraved plate of illustrations of electrical apparatus. A
little light browning and spotting, a very good copy bound in marbled
wrappers. Only three recorded copies on the market in the last 25
years. Scarce.
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