Luigi Galvani investigated the connection between living creatures and electricity. Earlier scientists had observed that static electricity and lightning were the same phenomenon. Galvani made frog legs twitch by applying two dissimilar metals. He came to the conclusion that animals generate electricity conducted by the metals. Alessandro Volta believed the opposite causation: that the setup generated the electricity and the legs reacted. Volta invented the battery after experimenting with various elements as the metals. Galvani's nephew Giovanni Aldini carried on his work and even experimented on the body of a condemned prisoner.

I had always thought the rise of Frankenstein's monster was a hilariously nonsensical application of the literary device of extending scientific explanations of natural phenomenon into magic (e.g. endless potential of atomic everything in the 50s, electric disturbances in ghost movies, reversing the polarity, quantum mechanics, genetic engineering, endless applications for graphene). We all know that lightning kills and injures. But it's not such a random jump between hearing of a corpse flinching, making a fist, and opening an eye (Aldini); and writing a horror story about a crazed scientist reversing death.

Funnily enough it turns out that all living things do generate electricity through pumping out sodium ions and pumping in potassium ions, creating a voltage across their cell membranes. But nowhere near enough to be observable on a macro scale.