2009년 4월 22일 수요일

Luigi Galvani

자료: Scientist, http://www.answers.com/topic/luigi-galvani


...(중략) By analogy with the frog's twitch, a person is said to be galvanized by any stimulus that causes a strong reaction.



Luigi Galvani
Luigi Galvani - Italian physician famous for making dead frogs' legs twitch.
Luigi Galvani - Italian physician famous for making dead frogs' legs twitch.
BornSeptember 9, 1737
BolognaPapal States
DiedDecember 4, 1798 (aged 61)
BolognaPapal States
InstitutionsUniversity of Bologna
Known forbioelectricity

Luigi Galvani (September 91737 – 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 twitched when struck by a spark.[1] He was a pioneer in modern obstetrics, and discovered that muscle and nerve cells produce electricity.

Contents

 [hide]

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, in which city he practiced, 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 genito-urinary 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 published in the 7th 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.

Late 1780s diagram of Galvani's experiment on frog legs.

Frogs' legs

In 1783, 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 earlie rballoonist 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. galvanisim is electrity by a medical reaction.


Galvani vs. Volta: Animal electricity or heat electricity?

Galvani'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, i.e. 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”.

....

Miscellaneous

  • Galvani's report of his investigations were mentioned specifically by Mary Shelley as part of the summer reading list leading up to an ad hoc ghost story contest on a rainy day in Switzerland—and the resultant novel Frankenstein—and its electrically reanimated construct.
  • Galvani's name also survives in the Galvanic cellGalvani potential, the galvanometer and galvanization.
  • The crater Galvani on the Moon is also named after him.
  • Galvani's brother, Mario Galvani, studied medicine and would frequently help Luigi.


댓글 없음:

댓글 쓰기