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The History of Bioelectromagnetism

Michael Faraday (1791–1867), a great distinguished British chemist and natural philosopher, was inter­

ested in bioelectromagnetism, in particular, in bioelectricity during his Grand Tour to Europe. In 1813,

Faraday, Sir Humphry Davy (1778–1829) and his wife traveled from Turin to Genoa. Faraday was much

interested in several water-spouts which he saw in the bay of Lerici, and then in Florence. In Genoa, they

visited Domenico Viviani (1772–1840), an Italian botanist and naturalist, professor at University of Genoa.

At that time, Prof Viviani caught the electric fsh torpedo in the bay of Lerici, and tried to investigate

whether the electric discharge of the torpedo is strong enough to decompose water (Hamilton, 2002).

Faraday studied with him the electric discharge from the torpedo. Te results of his torpedo experiments

proved that the identity of the electric power of the gymnotus or the torpedo was common electricity

(Faraday, 1839). He concluded that a single medium electrical discharge of the fsh is at least equal to the

electricity of a Leyden battery of 15 jars, containing 3,500 square inches of glass coated on both sides,

discharged to its highest degree (Motteday, 1922). During their Grand Tour, they visited from England, to

France, Belgium, Italy, Switzerland, Germany, and met André Marie Ampère (1775–1857), a French physi­

cist, professor at the Ėcole polytechnique, Dominique François Arago (1786–1853), a French physicist and

astronomer, Joseph Louis Gay-Lussac, Alessandro Guiseppe Antonio Anastasio Volta, Jean-Baptiste Biot

(1774–1862), a French physicist and mathematician, Sir Benjamin Tompson (Count von Rumford) (1756–

1819), the founder of Royal Institution of Great Britain, Wilhelm Heinrich Alexander von Humboldt, etc.

In their Grand Tour, various experiments were made by Sir Davy at each place, on iodine, and on the

electricity of the torpedo fsh. While at each place Faraday found some opportunities for helping satisfy his

craving for improvement (Jerrold, 1891). In their Grand Tour course, in Milan on June 17, 1814, he visited

Volta who was nearly 70 years old. Faraday, Sir Davy and his wife lef London on October 13, 1813, and

returned to England on April 23, 1815. Soon, Faraday engaged as Davy’s assistant at the Royal Institution.

Te time when they took their Grand Tour corresponded to the time of the Napoleonic Wars.

2.3.2.2 The Developing Stage

Until the nineteenth century, electricity and magnetism were considered as separate physical proper­

ties. In 1820, Hans Christian Oersted (1777–1851), professor of Natural Philosophy at the University of

Copenhagen, Denmark, observed that an electric current fow through a wire would move a compass

placed beside it. Tis showed that an electric current produced a magnetic feld which means that there

is a connection between electricity and magnetism. His great discovery made a new era which opened

the scientifc development in electromagnetism and bioelectromagnetism. Oersted sent a copy of his

experiments to Berlin, Paris, London, and other places. Soon, Oersted was ofered membership in the

Royal Society and received the Copley medal from its Society in late 1820. Within the next 45 years, this

great discovery was repeated by many scientists in the world.

Oersted’s work was published in a Latin pamphlet dated July 21, 1820. Only 3 months afer publica­

tion, on October 20, 1820, Jean Baptiste Biot (1774–1862) and Félix Savart (1791–1841), a French physicist,

gave together the theoretical concept of Oersted’s work, called later, the law of Biot-Savart. Tis law

states that the force between a wire with electric current fowing and a magnet pole is inversely pro­

portional to the distance between them. Later, Ampère generalized it and developed the mathematical

theory of electrodynamics (Ponchon et al., 2020). Soon afer, the translation of Oersted’s experiments

into English appeared in the Annals of Philosophy, and Faraday obtained a copy of Oersted’s paper from

Sir Davy in 1821 and began to repeat the experiments.

In 1824, Dominique Arago observed that when a magnetic needle was oscillating above or close of a

non-magnetic body (such as water or a metal), it gradually oscillated in arcs of less and less amplitude,

and he made a circular copper plate to revolve immediately beneath a magnetic needle or magnet, freely

suspended so that the latter would rotate in a plane parallel to that of the copper plate, and he found that

the needle tends to follow the circumvolution of the plate; that it will deviate from its true direction; and

that by increasing the velocity of the plate the deviation will increase until the needle passes to the oppo­

site point, when it will continue to revolve, and last rapidly so that the eye will be unable to distinguish

it (Mottelay, 1922). However, this phenomenon remained inexplicable.