In around 1786 at the University of Bologna in Italy, Professor Luigi Galvani carried out an experiment on a frog. By holding two strips of different metals to the dead frogs leg, he found that the leg actually twitched. He believed that the frogs leg must contain electricity. A gentleman called Alessandro Volta, who was a physics professor working at another university, disagreed with Galvani's assumption. Volta believed that the electricity was produced by the contact of the two metals, not the frogs leg.
Alessandro Volta proved his theory in 1800. He stacked up pairs of discs of two differing metals and then between them, he positioned a pad soaked with a weak acid. This caused a steady flow of electrical current. Alessandro Volta had invented the first electric battery. The 'lead acid' battery was later invented by Gastion Plante in 1850.
Since that time, scientists have discovered ways of making the battery more efficient. The batteries of today can now be of many varying sizes and strengths, and for a variety of purposes. The units in which electricity is measured are called volts, in reverence of the man who invented the battery.
