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38 some mysterious "electric life force," and the name of "Galvanism" was given by the scientists of the time to this supposed force. This term has survived even to this day, though, except in some medical writings, rather in a metaphorical than a scientific sense.

Galvani's conception of an electric life force held the field for only a short time; it was proved to be a misconception by Alexander Volta, Professor at the Pavia University, who showed by a conclusive experiment that the cause of electrification does not reside in the animal tissue at all, but in the contact between the two different metals. He took discs of different metals, such as copper and iron or copper and zinc, and laid one on the other. The discs must be perfectly flat so as to present to each other even contact surfaces. Volta in his classic experiment found that such discs, if separated after having been in contact for ever so short a time, show signs of electrification; one being positively, the other negatively charged. In this experiment there is no question of any life force residing in animal tissue, for no such tissue is being used. The discs are simply laid one on the other, touched on