March 20, 1800: Volta's Battery Shows Potential

1800: Italian physicist Alessandro Volta reports that he's developed a reliable source of electrical current. He's invented the wet-cell battery.

Volta had already created the electrophorus to create static electric charges and discovered methane before becoming professor of physics at the University of Pavia in 1779.

He disputed Luigi Galvani's contention that a frog's leg was producing the electricity that made it twitch. Volta thought the leg was simply responding to electricity from the metals that were touching it. The two men debated the science publicly, but remained friends -- despite clashes by their supporters. Volta, in fact, coined the word galvanism to honor his friend's contributions.

Volta theorized that electrical current was caused by the contact of dissimilar metals amid moisture. He went on to build a stack of alternating copper and zinc discs. Each pair of discs was separated from the next by cardboard that had been soaked in salty water. This voltaic pile produced continuous electrical current. Volta wrote about it to Joseph Banks, head of the Royal Society in London, who shared news of the invention with other scientists.

The results were literally electrifying and nearly immediate. Within weeks, William Nicholson and Anthony Carlisle had discovered that electrical current could decompose water into hydrogen and oxygen. Humphry Davy soon used this newly discovered electrolysis to discover potassium and other metals.

Emperor Napoleon of France, who ruled much of Italy at the time, was impressed by Volta's inventions. He made him first a knight, then a senator and finally a count.

Count Volta's name lives on, of course, as a unit of measure. The volt was officially established in 1881 as an electrical potential of 1 joule per coulomb of charge, or the electromotive force that will cause a current of 1 ampere to flow through a resistance of 1 ohm. It is used around the world.

(In other current events, it should be noted that West Africa's Volta River is not named for the Italian scientist. Its name comes from the Portuguese word for turn, either because it was a turnaround point for explorers or because of the river's own twists and turns.)

(Source: Various)