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Luigi Galvani

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Luigi Galvani
Luigi Galvani - Italian physician famous for pioneering bioelectricity.
Born(1737-09-09)September 9, 1737
DiedDecember 4, 1798(1798-12-04) (aged 61)
Known forBioelectricity
Scientific career
InstitutionsUniversity of Bologna

Luigi Galvani (September 9, 1737 – December 4, 1798) was an Italian physician and physicist who lived and died in Bologna. In 1771, he discovered that the muscles of dead frogs legs twitched when struck by a spark.[1] This was one of the first forays into the study of bioelectricity, a field that still today studies the electrical patterns and signals of the nervous system. He was cutting the frogs legs as he was doing an experiment as he believed that a frogs testicles were actually in their legs. He was quickly proved wrong by other biologists at the University of Pavia.

Early life

At first he thought about being a mechanic because he loved taking and dealing with spool testing. Later, his wish was to enter the church, but by his parents he was educated for a medical career. Galvani attended Bologna's medicine school and became a medical doctor like his father. At the University of Bologna, he was in 1762 appointed public lecturer in anatomy, and soon gained repute as a skilled though not eloquent teacher, and, chiefly from his researches on the organs of hearing and genitourinary tract of birds, as a comparative anatomist.

His celebrated theory of animal electricity he enunciated in a treatise, De viribus electricitatis in motu musculari commentarius (De vīribus ēlectricitātis in mōtu mūsculārī commentarius "Commentary on the Effect of Electricity on Muscular Motion") published in the seventh volume of the memoirs of the Institute of Sciences at Bologna in 1791, and separately at Modena in the following year, and elsewhere subsequently. In 1764, he married Lucia Galleazzi, a daughter of a professor at the University of Bologna and a well-liked woman of society. In 1772 Galvani became president of the University.

File:Galvani-frog-legs.PNG
Late 1780s diagram of Galvani's experiment on frog legs.

According to popular version of the story, Galvani dissected a frog at a table where he had been conducting experiments with static electricity. Galvani's assistant touched an exposed sciatic nerve of the frog with a metal scalpel, which had picked up a charge. At that moment, they saw sparks and the dead frog's leg kick as if in life. The observation made Galvani the first investigator to appreciate the relationship between electricity and animation — or life. This finding provided the basis for the current understanding that electrical energy (carried by ions), and not air or fluid as in earlier balloonist theories, is the impetus behind muscle movement. He is poorly credited with the discovery of bioelectricity.

Galvani called the term animal electricity to describe whatever it was that activated the muscles of his specimens. Along with contemporaries, he regarded their activation as being generated by an electrical fluid that is carried to the muscles by the nerves. The phenomenon was dubbed galvanism, after Galvani, on the suggestion of his peer and sometime intellectual adversary Alessandro Volta. Galvanism is electricity by a medical reaction.

Galvani vs. Volta: animal electricity or heat electricity?

Volta's investigations led shortly to the invention of an early battery, but not by Galvani, who did not perceive electricity as separable from biology. Galvani did not see electricity as the essence of life, which he regarded vitalistically. Galvani believed that the animal electricity came from the muscle. Galvani's associate Alessandro Volta, in opposition, reasoned that the animal electricity was a physical phenomenon, a metallic electricity.

While, as Galvani believed, all life is indeed electrical, specifically that all living things are made of cells and every cell has a cell potential, biological electricity has the same chemical underpinnings as the current between electrochemical cells, and thus can be recapitulated in a way outside the body, Volta's intuition was correct. Volta, essentially, objected to Galvani’s conclusions about "animal electric fluid", but the two scientists disagreed respectfully and Volta coined the term "galvanism" for a direct current of electricity produced by chemical action.[2] Thus, owing to an argument between the two in regard to the source or cause of the electricity, Volta built the first battery in order to specifically disprove his associate's theory. Volta's “pile” became known therefore as a voltaic pile.

Galvani’s landmarks in Bologna

Galvani’s home in Bologna has been preserved and can be seen in the central via Marconi. On the facade of the house, now a seat of a bank, there is a medallion with the face of Galvani and double inscription in Italian and Latin: "NATO ACCOLSI GALVANI E PIANSI ESTINTO. PER LUI FU L'UNO ALL'ALTRO POLO AVVINTO - GALVANUM EXCEPI NATUM LUXIQUE PEREMPTUM CUIUS AB INVENTO IUNCTUS UTERQUE POLUS" (I received the newborn Galvani; I cried him dead / He held together both the electric poles).

Galvani’s monument. In the square dedicated to him, facing the palace of the Archiginnasio, the ancient seat of the University of Bologna, a big marble statue has been erected to the scientist while observing one of his famous frog preparation.

Legacy

References

  1. ^ Luigi Galvani (1737-1798) – Eric Weisstein’s World of Scientific Biolgraph.
  2. ^ Luigi Galvani – IEEE Global History Network.
  •  Chisholm, Hugh, ed. (1911). Encyclopædia Britannica (11th ed.). Cambridge University Press. {{cite encyclopedia}}: Missing or empty |title= (help)