Alessandro Volta, Italian physicist, demonstrating his electric pile (battery), c1800 (c1870). Volta's (1745-1827) voltaic pile, an early form of battery, was the first source of current electricity. It consisted of two different metals, separated by chemicals in order to enable a flow of electricity. In 1775, he invented the electrophorus, a precursor of the induction machine, and in 1777 he invented an 'inflammable air' electric pistol. The unit of electromotive force 'volt' is named after him. From Les Merveilles de la Science by Louis Figuier. (Paris, c1870). (Colorised black and white print).