History of Medicine
During the 1790s, Italian physician Luigi Galvani demonstrated what we now understand to be the electrical basis of nerve impulses when he made frog muscles twitch by jolting them with a spark from an electrostatic machine. When Frankenstein was published, however, the word galvanism implied the release, through electricity, of mysterious life forces. "Perhaps," Mary Shelley recalled of her talks with Lord Byron and Percy Shelley, "a corpse would be reanimated; galvanism had given token of such things."
Illustration of Italian physician Luigi Galvani's experiments, in which he applied electricity to frogs legs; from his book De Viribus Electricitatis in Motu Musculari (1792).