Inlaid into the wooden floor of the basement at
the Faraday Museum of the Royal Institution in London is a representation
of a plump, green frog. The mosaic serves as a salutary reminder
that all of today’s electronic, marvels began with the twitching
of a frog’s leg. In Luigi Galvani’s (1737-1798) own
words:
“I had dissected and prepared a frog in the
usual way and while I was attending to something else I laid it
on a table on which stood an electrical machine at some distance
from its conductor and separated from it by a considerable space.
Now when one of the persons present touched accidentally and lightly
the inner crural nerves of the frog with the point of a scalpel,
all the muscles of the legs seemed to contract again and again as
if they were affected by powerful cramps”.
The twitchings were, almost literally, the birth
pangs of electrophysiology, and they were soon to show the way to
the voltaic pile and current electricity.
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
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.
Shortly before he died, Galvani
was dismissed from his professorship at the University of Bologna,
because he refused to swear allegiance to Napoleon’s Cisalpine
Republic. As the Dictionary of Scientific Biography poignantly states:
Galvani “died in poverty and sorrow”.
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