Alesandro Volta, Italian physicist and inventor, c 1800.
© Science Museum / Science & Society Picture Library
Engraved portrait of Volta from the frontispiece to the first volume of his 'Collezione dell' opere del cavaliere Conte Alesandro Volta', published in Florence in 1816. Count Alesandro Giuseppe Anastasio Volta (1745-1827) was the inventor of the voltaic pile, an early battery and 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 SI (international standard) unit of electromotive force, the volt (V), is named after him.