Luigi Galvani (1737-1798) was an Italian scientist. He accidentally noticed that severed frogs’ legs twitched when the nerve was touched with a pair of metal scissors during a thunderstorm. Alessandro Volta (after whom the volt is named) explained why this happened. It was because an electrical current was produced between two metals, which provided the stimulation to the nerves. This discovery later led to the realization that the nervous system works by means of electrical signals.
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