Alessandro Volta

Alessandro Volta (1745-1827)

A century and a half after Galileo's death, something of scientific importance was to develop in Italy. Volta, a former high school physics teacher, found that it was the presence of two dissimilar metals, not the frog leg, that was critical. In 1800, after extensive experimentation, he developed the voltaic pile. The original voltaic pile consisted of a pile of zinc and silver discs and between alternate discs, a piece of cardboard that had been soaked in saltwater. A wire connecting the bottom zinc disc to the top silver disc could produce repeated sparks. No frogs were injured in the production of a voltaic pile.

Count Alessandro Volta was born in Como, Italy, into a noble family. The Italian physicist Alessandro Giuseppe Antonio Anastasio Volta was the inventor of the voltaic pile, the first electric battery. In 1775 he invented the electrophorus, a device that, once electrically charged by having been rubbed, could transfer charge to other objects. Between 1776 and 1778, Volta discovered and isolated methane gas.

Voltaic Piles

When Luigi Galvani's experiments with "animal electricity" were published (1791), Volta began experiments that led him to theorize that animal tissue was not necessary for conduction of electricity. Proof of this theory was the battery, which Volta invented in 1800. He built in 1800 the first electrical pile, or battery: a series of metal disks of two kinds, separated by cardboard disks soaked with acid or salt solutions. This is the basis of all modern wet-cell batteries, and it was a tremendously important scientific discovery, because it was the first method found for the generation of a sustained electrical current.

Volta built different piles using thirty, forty or sixty elements. This enabled him to study the action of the pile on the electric fluid, depending on the number of elements, and he confirmed that the electric shock increased in intensity with the number of elements used in the pile. If more than twenty elements were used, it became painful. The first piles constructed by Volta comprised alternating zinc and copper discs. Each was separated from its neighbor by a piece of cloth or card dampened by an acid solution. The column was supported by three vertical glass rods.

However, regarding Galvani's biological experiments, Volta effectively rejected the idea of an "animal electric fluid". The Galvani vs. Volta debate was one of the most interesting episodes in the history of science, and was devoid of personal animosity, because Galvani and Volta were both gentleman and friends, and also had high scientific principles. In fact, Volta, who generously coined the term galvanism, wrote that Galvani's work "contained one of the most beautiful and most surprising discoveries." Upon demonstrating the workings of the voltaic pile to the French Academy of Science, he was made into a count of Lombardy by Napoleon Bonaparte, who had dominated that part of Italy.

The emperor of Austria made him director of the philosophical faculty at the University of Padua in 1815, 12 years before the day he was to die. The volt as we hear today, was named after Alessandro Volta in 1881 in honor and memory of him.

In a nutshell

Volta invented the so-called Volta's pile (or voltaic pile); the electrophorus; an electric condenser; and the voltaic cell. The volt, a unit of electrical measurement, is named for Volta.

The beginnings of Volta's scientific activity are extremely precocious: even without any university preparation in 1763 at the age of only 18, he is already engaged in scientific correspondence with the major electric authorities of the time, Father Beccaria and the Abbot Nollet, to whom he courageously puts forward his own theories on the matter. Around 1765 Volta is a frequent visitor to the home of Giulio Cesare Gattoni (1741-1809) where he has the chance to use the physics laboratory which Gattoni had built between 1764 and 1765. His interest in electrology is stimulated by his friend Gattoni's research work. It was thanks to him, that, according to Giambattista Giovio, Volta "acquired most of his reputation in Europe".

Ð'* 1745 - February 18 - Born in Como in northern Italy of the patrician family of Filippo and Maddalena Volta.

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1760 - November - Enrolled in the Seminary in Como for studies in philosophy and the classics. He mastered English, French and Latin and learned to read Dutch and Spanish.

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1763 - His interest in physics and chemistry led to correspondence on electricity with the Abbe Nollet in Paris and later with Prof. Beccaria in Turin.

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1769 - April 18 - His first study in electricity , "De vi attractiva ignis electrici", was published in Como. His second work appeared in 1771.

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1774 - October 22 - Appointed director of the Royal School in Como. In November 1775 he became professor of Physics.

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1775 - Announced the invention of the electrophorus, an electrical generating device that attracted wide notice, in a letter to Joseph Priestley.

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1776 - November 3 - Observed the bubbling of methane in swamps and began the publication of a series of letters on his experiments with marsh gas that led to the development of gas lanterns electrically ignited, and the "electric pistol."

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1777 - April 18 - In a letter to Prof. Barletti at Pavia, Volta described a possible electrical signaling system from Como to Milan.

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