Volta , Count Alessandro Giuseppe Antonio Anastasio

(1745–1827) Italian physicist

Volta, who was born at Como in Italy, grew up in an atmosphere of aristocratic religiosity with almost all his male relations becoming priests. However, Volta decided early that his life's work lay in the study of electricity and, by the age of 24, had developed his own version of Benjamin Franklin's electrical fluid theory. In 1774 he started teaching physics at the gymnasium in Como, where, a few months later, he invented the electrophorus – a device for producing electric charge by friction and, at the time, the most efficient way of storing electric charge. On the strength of this invention he was promoted, in 1775, to the position of professor of physics at Como and, three years later, took up a similar appointment at Pavia University. Here, stimulated by the experiments of his friend Luigi Galvani, he started investigating the production of electric current. In 1795 he was appointed rector of Pavia but his work was disturbed by the political upheavals in Lombardy at the time. The state was oscillating between French and Austrian control in the Napoleonic campaigns and in 1799–1800 the Austrians closed the university.

Volta chose this time to make public his great discovery that the production of electric current did not need the presence of animal tissue, as Galvani and others had supposed. Volta produced the famous voltaic pile, consisting of an alternating column of zinc and silver disks separated by porous cardboard soaked in brine. This instrument revolutionized the study of electricity by producing a practical source of current, leading almost immediately to William Nicholson's decomposition of water by electrolysis and later to Humphry Davy's discovery of potassium and other metals by the same process.

In 1800 Napoleon returned in victory to Pavia, reopened the university, and invited Volta to Paris to demonstrate his pile. He awarded Volta the medal of the Legion of Honor and made him a count. In his honor the unit of electric potential (or potential difference or electromotive force) was called the volt.