Birthplace: Newington, Surrey, England
Died: 25 August 1867
Best Known As: Inventor of the first dynamo
Although he had little formal education, Michael Faraday went on to become one of the most influential scientists in the field of electricity. He spent his professional career in the laboratory of the Royal Institution in London (1813-62), where he got his start as an assistant in 1813 to Sir Humphry Davy. By 1825 he had worked his way up to being laboratory director, and in 1833 he was made a professor of chemistry. In the lab he had great success with electrochemistry, and he even has an electrical unit named after him (a faraday is an amount of electricity measured during electrolysis). Faraday built the first dynamo, a copper disk that rotated between the poles of a permanent magnet and produced an electromotive force (something that moves electricity). His work in electromagnetic induction led to the development of modern dynamos and generators. Faraday also discovered the compound benzene.
The English physicist and chemist Michael Faraday (1791-1867) discovered benzene and the principles of current induction.
One of a blacksmith's 10 children, Michael Faraday was born on Sept. 22, 1791, in Newington, Surrey. The family soon moved to London, where young Michael picked up the rudiments of reading, writing, and arithmetic. At the age of 14 he was apprenticed to a bookbinder and bookseller. He read ravenously and attended public lectures, including some by Sir Humphry Davy.
Faraday's career began when Davy, temporarily blinded in a laboratory accident, appointed Faraday as his assistant at the Royal Institution. With Davy as a teacher in analytical chemistry, Faraday advanced in his scientific apprenticeship and began independent chemical studies. By 1825 he discovered benzene and had become the first to describe compounds of chlorine and carbon. He adopted the atomic theory to explain that chemical qualities were the result of attraction and repulsion between united atoms. This proved to be the theoretical foundation for much of his future work.
Faraday had already done some work in magnetism and electricity, and it was in this field that he made his most outstanding contributions. His first triumph came when he found a solution to the problem of producing continuous rotation by use of electric current, thus making electric motors possible. Hans Oersted had discovered the magnetic effect of a current, but Faraday grasped the fact that a conductor at rest and a steady magnetic field do not interact and that to get an induced current either the conductor or the field has to move. On Aug. 29, 1831, he discovered electromagnetic induction.
During the next 10 years Faraday explored and expanded the field of electricity. In 1834 he announced his famous two laws of electrolysis. Briefly, they state that for any given amount of electrical force in an electrochemical cell, chemical substances are released at the electrodes in the ratio of their chemical equivalents. He also invented the voltameter, a device for measuring electrical charges, which was the first step toward the later standardization of electrical quantities.
Faraday continued to work in his laboratory, but his health began to deteriorate and he had to stop work entirely in 1841. Almost miraculously, however, his health improved and he resumed work in 1844. He began a search for an interaction between magnetism and light and in 1845 turned his attention from electrostatics to electromagnetism. He discovered that an intense magnetic field can rotate the plane of polarized light, a phenomenon known today as the Faraday effect. In conjunction with these experiments he showed that the magnetic line of force is conducted by all matter. Those which were good conductors he called paramagnetics, while those which conducted the force poorly he named diamagnetics. Thus, the energy of a magnet is in the space around it, not in the magnet itself. This is the fundamental idea of the field theory.
Faraday was a brilliant lecturer, and through his public lectures he did a great deal to popularize science. Shortly after he became head of the Royal Institution in 1825, he inaugurated the custom of giving a series of lectures for young people during the Christmas season. This tradition has been maintained, and over the years the series have frequently been the basis for fascinating, simply written, and informative books.
On Aug. 25, 1867, Faraday died in London.
The admiration of physicists for Faraday has been demonstrated by naming the unit of capacitance the farad and a unit of charge, the faraday. No other man has been doubly honored in this way. His name also appears frequently in connection with effects, laws, and apparatus. These honors are proper tribute to the man who was possibly the greatest experimentalist who ever lived.
Further Reading
Much has been written about Faraday, but the student should first read the account by his successor at the Royal Institution, John Tyndall, Faraday as a Discoverer (1961). The sketch of Faraday in James Gerald Crowther, Men of Science (1936), is also recommended. Leslie Pearce Williams, Michael Faraday: A Biography (1965), appraises Faraday's work in relation to modern science and contains many previously unpublished manuscripts.
Famous British physicist, born in London on September 22, 1791. He became an assistant to Sir Humphry Davy and later became celebrated for his brilliant discoveries relating to electricity and chemistry. Faraday's well-known saying, "Nothing is too amazing to be true," apparently was not meant to cover table turning. It was, for him, too amazing to be true. His noted theory that table movements were caused by unconscious muscular pressure was first advanced in a letter to the Times of June 30, 1853. To prove it, he prepared two small flat boards a few inches square, placed several glass rollers between them and fastened the whole together with a couple of rubber bands so that the upper board would slide under lateral pressure to a limited extent over the lower one. A light index fastened to the upper board would betray the least amount of sliding.
During experiments this is just what happened. The upper board always moved first, which demonstrated that the fingers moved the table and not the table the fingers. Faraday also found that when the sitters learned the meaning of the index and kept their attention fixed on it, no movement took place. When it was hidden from their sight it kept on wavering, although the sitters believed that they always pressed directly downward. However, the pressure of the hands was trifling and was practically neutralized by the absence of unanimity in the direction. The sitters never made the same movement at the same moment.
For this reason, and for the weightier one that tables moved without contact as well, his theory was soon found inadequate. According to Charles Richet, it was Michel Chevreul, the famous French chemist, who originally evolved the theory of un-conscious muscular pressure. Chevreul's book, however, did not appear until 1854, a year after Faraday's explanation was published.
In later years many attempts were made to prove to Faraday the reality of psychic phenomena, but he was too obstinate. "They who say these things are not competent witnesses of facts," he wrote in 1865. To an invitation to attend the first séance of the Davenport brothers he returned the answer, "If spirit communications, not utterly worthless, should happen to start into activity, I will trust the spirits to find out for themselves how they can move my attention. I am tired of them."
Faraday was a member of the Sandemanians, an obscure religious sect holding rigid biblical views. When Sir William Crookes inquired of Faraday how he reconciled science with religion, he received the reply that he kept his science and religion strictly apart.
At the time of the Home-Lyon trial (see D. D. Home), a Professor Tyndall, in a letter in Pall Mall Gazette (May 5, 1868), wrote that, years before, Faraday had accepted an invitation to examine Home's phenomena, but his conditions were not met and the investigation fell through. When the original correspondence on the subject between Faraday and Sir Emerson Tennant was published, it appeared that one of Faraday's conditions was, "If the effects are miracles, or the work of spirits, does he (Home) admit the utterly contemptible character, both of them and their results, up to the present time, in respect either of yielding information or instruction or supplying any force or action of the least value to mankind?" Robert Bell, the intermediary for the proposed séance, found Faraday's letter so preposterous that, without consulting Home, he declined his intervention. Home, when he learned about it, was duly indignant.
Professor Tyndall—as an arch skeptic—commended Faraday's attitude, but those interested in psychical research assumed the contrary position. "The letter," writes Frank Pod-more in Modern Spiritualism (1902), "was, of course, altogether unworthy of Faraday's high character and scientific eminence, and was no doubt the outcome of a moment of transient irritation. The position taken was quite indefensible. To enter upon a judicial inquiry by treating the subject-matter as a chose jugée was surely a parody of scientific methods."
Faraday died August 25, 1867. In a series of séances between 1888 and 1910 in Spring Hall, Kansas, the presiding spirit claimed to be Faraday, and his communications were published in four books by A. Aber: Rending of the Veil, Beyond the Veil, The Guiding Star, and The Dawn of Another Life. A second set of communications reportedly from Faraday were received by an anonymous medium who called herself (or himself) the "Mystic Helper." The messages were received sporadically beginning in 1874 and were finally published in 1924.
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