Luigi Galvani (1737-1798) conducted a series of experiments on "animal electricity." He applied current to the nerves of a frog and observed the contractions of the muscles in its legs. Among other things, Galvani discovered that when connected pieces of iron and brass were applied to frog's legs, they caused them to twitch.
He speculated that electricity was stored in the leg, a theory that attracted a widespread following but was later proven wrong. The words "galvanic," "galvanize" and "galvanometer" are named after him.