Luigi Galvani

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Luigi Galvani
Luigi Galvani, oil-painting.jpg
Luigi Galvani Italian physician famous for pioneering bioelectricity
Born (1737-09-09)September 9, 1737
Bologna, Papal States
Died December 4, 1798(1798-12-04) (aged 61)
Bologna, Papal States
Institutions University of Bologna
Known for Bioelectricity
[animal electricity]

Luigi Aloisio Galvani (Latin: Aloysius Galvani) (September 9, 1737 – December 4, 1798) was an Italian physician, physicist and philosopher who had also studied medicine and had practiced as a doctor, who lived and died in Bologna. In 1780, he discovered that the muscles of dead frogs legs twitched when struck by a spark.[1]:67-71 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.

Early life[edit]

Luigi Galvani was born to Domenicoo and Barbara Foschi in Bologna, Italy. His father was a goldsmith and his mother was Domenico's fourth wife. His family was not aristocratic, but they could afford to send at least one of their sons to study at a university. At first Galvani wished to enter the church so he joined a religious institution, Oratorio dei Padri Filippini, at 15 years old. He was going to take his religious vows, but his parents persuaded him not to do so. In approximately 1755, Galvani entered the Faculty of the Arts of the University of Bologna. Galvani attended the medicine course, which lasted four years, and was characterized by its 'bookish' teaching. Texts that dominated this course were by Hippocrates, Galen, and Avicenna.

Another discipline Galvani learned alongside of medicine was surgery. He learned the theory and the practice. This part of his biography is typically overlooked, but it helped with his experiments with animals and helped familiarize Galvani with the manipulation of a living body.

In 1759, Galvani graduated with degrees in medicine and philosophy. He applied for a position as a lecturer at the university. Part of this process required him to defend his thesis on June 21, 1761. In the following year, 1762, he became a permanent anatomist of the university and was appointed honorary lecturer of surgery. That same year he married Lucia Galeazzi, daughter of one of his professors, Gusmano Galeazzi. Galvani moved into the Galeazzi house and helped his research. When Galeazzi died in 1775, Galvani was appointed professor and lecturer in Galeazzi's place.

Galvani moved from the position of lecturer of surgery to theoretical anatomy and obtained an appointment at the Academy of Sciences in 1776. His new appointment consisted of the practical teaching of anatomy, which was conducted through human dissections and the use of the famous anatomical waxes.

As a "Benedectine member" of the Academy of Sciences, Galvani had specific responsibilities. His main responsibility was to present at least one research paper every year at the Academy, which Galvani did until his death. There was a periodical publication that collected a selection of the memoirs presented at the institution, and it was sent around to main scientific academies and institutions around the world. However, since publications then were so slow, sometimes there were debates on priority of the topics used. One of these debates occurred with Antonio Scarpa. This debate caused Galvani to give up the field of research that he had presented on four years in a row: the hearing of birds, quadrupeds, and humans. Galvani had announced all of the findings in his talks, but had yet to publish them. It is suspected that Scarpa attended Galvani's public dissertation and may have taken claim on some of Galvani's discoveries without crediting him.

Galvani then began taking an interest in the field of "medical electricity." This field emerged in the middle of the 18th century, following the electrical researches and the discovery of the effects of electricity on the human body.[2]

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

The beginning of Galvani's experiments with bioelectricity has a popular legend which says that Galvani was slowly skinning a frog at a table where he had been conducting experiments with static electricity by rubbing frog skin. 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 kicked 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 new understanding that the impetus behind muscle movement was electrical energy carried by a liquid (ions), and not air or fluid as in earlier balloonist theories.

Galvani coined the term animal electricity to describe the force 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. Galvani is properly credited with the discovery of bioelectricity. Today, the study of galvanic effects in biology is called electrophysiology, the term galvanism being used only in historical contexts.

Galvani vs. Volta: animal electricity or heat electricity?[edit]

Electrodes touch a frog, and the legs twitch into the upward position[3]

Volta, a professor of experimental physics in the University of Pavia, was among the first scientists who repeated and checked Galvani’s experiments. At first, he embraced animal electricity. However, he started to doubt that the conductions were caused by a specific electricity intrinsic to animal's legs or other body part. Volta believed that the contractions depended on the metal cable Galvani used to connect nerves and muscles in his experiments.[4]

Volta's investigations led shortly to the invention of an early battery. Galvani believed that the animal electricity came from the muscle in its pelvis. Volta, in opposition, reasoned that the animal electricity was a physical phenomenon caused by rubbing frog skin and not a metallic electricity.

Every cell has a cell potential; biological electricity has the same chemical underpinnings as the current between electrochemical cells, and thus can be duplicated 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.[5] 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.

After the controversy with Volta, Galvani kept a low profile partly because of his attitude towards the controversy, and partly because his health and spirits had declined, especially after the death of his wife, Lucia, in 1790.

Since Galvani was reluctant to intervene in the controversy with Volta, he trusted his nephew, Giovanni Aldini, to act as the main defender of the theory of animal electricity.[6]

Galvani’s landmarks in Bologna[edit]

Luigi Galvani's monument in Piazza Luigi Galvani (Luigi Galvani Square), in Bologna

Galvani’s home in Bologna has been preserved and can be seen in the central.

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 experiments.

Liceo Ginnasio Luigi Galvani. This famous secondary school (liceo) dating back to 1860 was named after Luigi Galvani.

Death and legacy[edit]

Galvani actively investigated animal electricity until the end of his life. The Cisalpine Republic, a French client state founded in 1797 after the French occupation of Northern Italy, required every university professor to swear loyalty to the new authority. Galvani, who disagreed with the social and political confusion, refused to swear loyalty, along with other colleagues. This led to the new authority depriving him of all his academic and public positions, which took every financial support away. Galvani died in Bologna, in his brother’s house, depressed and in poverty, on December 4, 1798.[7]

Galvani's legacy includes:

See also[edit]

References[edit]

  1. ^ Whittaker, E. T. (1951), A history of the theories of aether and electricity. Vol 1, Nelson, London 
  2. ^ Bresadola, Marco (15 July 1998). "Medicine and science in the life of Luigi Galvani". Brain Research Bulletin 46 (5): 367–380. 
  3. ^ David Ames Wells, The science of common things: a familiar explanation of the first principles of physical science. For schools, families, and young students., Publisher Ivison, Phinney, Blakeman, 1859, 323 pages (page 290)
  4. ^ Bresadola, Marco (15 July 1998). "Medicine and science in the life of Luigi Galvani". Brain Research Bulletin 46 (5): 367–380. 
  5. ^ Luigi Galvani – IEEE Global History Network.
  6. ^ Bresadola, Marco (15 July 1998). "Medicine and science in the life of Luigi Galvani". Brain Research Bulletin 46 (5): 367–380. 
  7. ^ Bresadola, Marco (15 July 1998). "Medicine and science in the life of Luigi Galvani". Brain Research Bulletin 46 (5): 367–380. 

Works[edit]

External links[edit]