DNAprint Genomics (DNAG)

[stakddek]

Early Electric Experiments -- NOT FOR FROGDREAMING!

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http://www.geocities.com/bioelectrochemistry/galvani.htm

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[excerpted portion}

Numerous ingenious observations and experiments have been credited to him; in 1786, for example, he obtained muscular contraction in a frog by touching its nerves with a pair of scissors during an electrical storm. Again, a visitor to his laboratory caused the legs of a skinned frog to kick when a scalpel touched a lumbar nerve of the animal while an electrical machine was activated. Galvani assured himself by further experiments that the twitching was, in fact, related to the electrical action. He also elicited twitching without the aid of the electrostatic machine by pressing a copper hook into a frog's spinal cord and hanging the hook on an iron railing. Although twitching could occur during a lightning storm or with the aid of an electrostatic machine, it also occurred with only a metallic contact between leg muscles and nerves leading to them. A metallic arc connecting the two tissues could therefore be a substitute for the electrostatic machine.


In a very careful series of experiments in which he fastened "brass hooks in their [the frogs'] spinal cord to an iron railing which surround a certain hanging garden of my house" Galvani noticed that the frogs' legs went into contractions "not only when the lightning flashed but even at times when the sky was quiet and serene." In the contact between the brass hooks and the iron railing, Galvani came tantalizingly close to the contact theory later advanced by his fellow-countryman, Allesandro Volta. However, Galvani chose to interpret his results in terms of "animal electricity," which proclaimed that the structure of the muscle retained a "nerveo-electrical fluid" similar to that of an electric eel.

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Credit to Ben Franklin who I believe was a step or two ahead of Galvani during this era.

Stakddek