'Contraction of the muscles of a frog'.
© Science Museum / Science & Society Picture Library
Illustration showing a frog's legs. Whilst investigating the effects of electrostatic stimuli applied to the muscles of frogs, Italian physiologist Luigi Galvani (1737-1798) discovered he could make a muscle twitch by touching the nerve with metal (a pair of scissors for example) without a source of electrostatic charge. He called this phenomenon 'animal electricity'. The term 'galvanise' -to shock or excite into action -takes its name from him.