VOLTA, ALESSANDRO. — Distinguished physicist, of a noble family of Como, born there on 18 February 1745 and died there on 5 March 1827.
To him we owe the discovery of the electric current, from which followed most of the modern progress of physics, which in turn transformed, and is still transforming, the standard of living of a large part of humanity. For this reason V. is generally known everywhere as the great discoverer and the first producer of persistent electric currents by means of the pile he invented in 1799.
At the time of V.’s youth, electricity, known in rudimentary form for a full twenty-four centuries, was finally being considered more extensively following Guerrike’s invention of the first friction machine and its subsequent improvements, which permitted its abundant production and collection in a dry atmosphere. But while attention was almost universally directed toward the consideration and celebration of the most conspicuous electrical phenomena, such as long sparks and their various effects, the shock passing through chains of people holding hands, and the like, the young V., barely eighteen years old, thought that many electrical phenomena ought to be capable of interpretation through laws analogous to those of Newtonian attraction at very small distances and through contact between different bodies. In 1763 he communicated this idea to the then famous ab. Nollet, who praised and encouraged him. This was the idea that much later was to lead him to the pile.
From then on V. proceeded according to the principle of observing, listening, comparing, and thinking before speaking, recalling the Newtonian phrase that discoveries are made by thinking about them. Quietly, in his ancestral home, he experimented with very modest means until 1755, that is, until his thirtieth year, initially publishing privately two memoirs addressed respectively to p. Giov. Battista Beccaria of the University of Turin and to abbot Spallanzani of the University of Pavia, and finally constructing the electrophorus, which he immediately (1775) announced and described to C. Priestley of the Royal Society of London. The discovery of the electrophorus is of the greatest importance because, as Arago said, beneath the utmost simplicity and in the smallest volume, it offers an inexhaustible supply of electric fluid in every state of the atmosphere. It represents the most elementary of the various influence machines, the only ones still in use today, all of them derived from II. This discovery earned V. Como, a position he held until his call to the University of Pavia in 1778. His scientific activity at these two institutions, although often interrupted by long journeys undertaken to establish instructive contacts with the leading personalities and scientific institutions of Europe, was remarkable. It is enough to recall the discovery of methane gas; the clarification of the concepts of electrical capacity and tension; the inventions, in addition to the already mentioned electrophorus, of the electroscope and the condensation electrometer, the first true measuring instrument in the field of electrology; and his theory concerning the laws of the expansion of fluids, particularly the uniform expansion of air for each degree of temperature—all widely employed everywhere and serving as foundations for further research and progress.
Finally, in 1791, the well-known publication by L. Galvani, De viribus electricitatis in motu musculari commentarius, drew V.’s attention to this interesting subject. Applying the principle of thinking the matter through, after a few months V. discovered the error in Galvani’s theory: it was not animal electricity but metallic electricity, residing not in the nerves of animals but caused by the different nature of the metals placed in contact with one another.
The already illustrious V., aged forty-six, finally made use of the first scientific ideas of the eighteen-year-old, and began the famous long controversy with Galvani which, having already virtually concluded in V.’s favor, led him almost inevitably in 1799 (the year after Galvani’s death) to the invention of the pile, which he modestly claimed to have found along his path. Indeed, convinced that tensions (now they would be called potential differences) resided in the contacts between heterogeneous metals, during the years 1797–99 he sought, through repeated experiments, a way to multiply the metallic couples (silver and zinc) and to construct a device that would raise the electric tension to a high degree. For this purpose he thought of interposing between the metallic couples a moist layer, or second-class conductor, and was able to observe that the electric tension increased proportionally to the number of couples. It is to this that V. refers when he says: «This is the great step I took at the end of 1799, a step which led me soon to the construction of the new shocking apparatus», referring to the shocks he felt in his hands and arms when he touched the two ends of his device with both hands.
Only on 20 March 1800 did V. describe, in the celebrated letter to G. Banks, president of the Royal Society of London, his little machine, whose effects resembled those of the electric organ of the Raja torpedine. The machine was initially called by V. an artificial electric organ, then an electromotive apparatus, or also a column apparatus, on account of the form it had at that time. The name pile subsequently prevailed, often with the addition of galvanic, as used by the French.
The Voltaic discovery produced an immense echo everywhere and immediately raised the question «whether the effects of the pile could be explained to us by the new laws of electricity or whether it was necessary for this purpose to admit another particular fluid». And it was again V. who demonstrated the identity of the two fluids, galvanic and electric. On 7 September 1801, at the Institute of France, in the presence of First Consul Bonaparte, V. demonstrated and discussed his great discovery.
Retired at the end of 1804 after thirty years of teaching, V. was subsequently appointed by Napoleon (king of Italy) a member of the Legion of Honour, senator of the Kingdom, and count of the Kingdom of Italy. Following the fall of the Italian Kingdom, after a brief critical period caused by political disturbances, although appointed by the succeeding Austrian government director of philosophical studies at the University of Pavia, V. withdrew into private life between Como and his country residence at Camnago, where his remains rest, honored in a special little temple.
(from Les écrivains célèbres, edited by R. Queneau, II, Paris 1861, tau, opposite p. 186)
VOLTAIRE, FRANÇOIS-MARIE AROUET — Portrait, engraved from a drawing made from life (1778) — Paris, Cabinet of Prints.
not perverted by vices and passions, every well-disposed soul cannot fail to embrace and love it.”