National Geographic : 1949 Apr
Michael Faraday (1791-1867) " FATHER OF THE AGE OF ELEC 'TRICITY" is a title that may be prop erly conferred upon Michael Faraday. In 1831 he gave to the world the epoch-making discovery that an electric current can induce another current in a different circuit. Every electric motor and dynamo in use today operates upon this principle, electro magnetism. When a bar magnet is moved near or through the center of a coil of wire, a current flows through the wire, although the wire and magnet are not connected. When the magnet is moved back and forth, the current in the wire changes its direction of flow accordingly. Likewise, if a coil of wire through which a current is flowing is moved in the vicinity of another coil, a current will flow momentarily through the second coil. Faraday was born at Newington Butts, now a part of London, the son of a blacksmith. He once said, "I love a smith's shop and everything related to smithery. My father was a smith." Young Faraday was apprenticed to Riebau, a news agent and bookbinder for whom he at first delivered papers. A customer, a Mr. Iance, enabled the boy to hear a lecture by Sir Humphry Davy at the Royal Institution, and Faraday was enthralled. He kept notes of the lectures, which he illustrated and bound and, on his employer's advice, sent to Davy. In afterlife Faraday wrote: "When I was a bookseller's apprentice, I was very fond of experiment, and very averse to trade . . . My desire to escape from trade . . . induced me at last to take the bold and simple step of writing to Sir Humphry Davv." On December 24, 1812, a knock on the door announced Davy's coachman with a note asking Faraday to call at the Royal Institu tion the next day, and he was hired by Davy at a weekly wage of 25 shillings. Six months later Davy took Faraday as his secretary-assistant on a European tour, during which he consorted with the leading scientists of the day. This tour, priceless to Faraday, took for him the place of a university training. Faraday worked out his problems for the sheer joy of solving them, leaving to others any practical application. Once, after he had given a public demonstration of the induction of electric currents, a lady inquired what use ful service could come of it. In reply, the physicist asked, "Can you tell me what is the use of a newborn babv?" It is interesting that the American Joseph Henry, Secretary of the Smithsonian Institu tion, working independently, had made the same basic discovery as Faraday and perhaps even earlier, though Faraday was the first to publish his findings. Years later, on a visit to England, Henry's superlative laboratory technique drew from the watching Faraday the spontaneous and delighted tribute of a shout, "Hurrah for the Yankee!" In proving the definite and measurable chemical action of electricity, Faraday coined a vocabulary, including such words as "elec trode," "electrolyte," anionn," "cation," "an ode," and "cathode." which, indispensable today, suggest the vast results of his research. His discovery of benzene in 1825 gave to subsequent organic chemists the first of a series of coal-tar hydrocarbons. The concept of the "magnetic field," the lines of force surrounding a magnet, also was worked out by Faraday. He studied steel alloys, produced new kinds of optical glass, and did important work on the liquefaction of gases. Faraday was associated with the Royal Institution for 54 years, becoming director of the laboratory in 1825. He refused a knighthood, preferring to remain "plain Michael Faraday to the last." Closely associated with Faraday are the names of two other British scientists of first rank, Sir Humphry Davy (page 527) and James Clerk Maxwell. Davy (1778-1829), as professor of chemis try at the Royal Institution, recognized Fara day's genius and opened the world of science to him. Born at Penzance, Cornwall. he first was apprenticed to a surgeon-apothecary be fore becoming interested in chemistry. He is most noted for his invention of the miner's safety lamp, which put an end to the disastrous explosions of firedamp gas set off by the open flames of lamps in mines. He found that a metal screen with small apertures placed over the flame would prevent explosions from being touched off. Lamps of this type are still in general use in mines to test for the presence of firedamp. Davy also discovered the anesthetic prop erties of nitrous oxide, known as "laughing gas," by experimenting with its effects upon himself. He was the first to isolate potassium and sodium by running electrical currents through solutions. This laid the groundwork for the process of electrolysis, the tearing apart of substances by electricity, in wide use today. Davy discovered five new elements. James Clerk Maxwell (1831-1879) was the first to show theoretically that electro magnetic waves are propagated through space at the speed of light. All radio communica tion, television, and radar are based in essence on work inspired by Maxwell's pioneering theories. Born in Edinburgh, Maxwell di rected the founding of the Cavendish Labora tory at Cambridge University, where he was professor of experimental physics.