Charles Wheatstone

English physicist

• Born: February 6, 1802
• Birthplace: Barnswood, Gloucester, England
• Died: October 19, 1875
• Place of death: Paris, France

Wheatstone was a prolific inventor in the fields of acoustic and electric technology. He is best known for his invention of new musical instruments and his contributions to the development of telegraphy.

Primary fields: Communications; music; physics

Primary inventions: Enchanted lyre; electric telegraph

Early Life

Charles Wheatstone was the second of four children and the younger son of William Wheatstone, a shoemaker, and his wife, Beata. In 1806, the family moved to Pall Mall in London, where the elder Wheatstone became a music teacher; his pupils included Princess Charlotte. Charles attended several private schools, finding the experience uncomfortable because of his chronic shyness. At the age of fourteen, he was apprenticed to his uncle, also named Charles Wheatstone, who had a business in the Strand manufacturing musical instruments. The young Charles found that experience as uncongenial as school and returned home, immersing himself in books—including a treatise on electricity by Alessandro Volta, which he translated from French with the aid of a dictionary.

Wheatstone’s brief experience of working with his uncle cultivated a fascination with acoustic science and made a considerable impression when he exhibited an “acoucryptophone,” or “enchanted lyre.” The instrument suspended from the ceiling played by itself as if by magic, though it was actually resonating with the sounds (transmitted by wire) of musical instruments played in another room. The idea occurred to him of using electrical wires to carry signals over much longer distances, making broadcast music possible. Though it never came to fruition, the idea inspired him to coin the term “telephone” to describe such a device. His coinage “microphone,” describing a device for augmenting feeble sounds—what would nowadays be called an amplifier—also failed to catch on.

When Charles Wheatstone the instrument maker died in 1823, his nephew William took over the business, and the young Charles returned to the Strand, apparently feeling able to work with his older brother. He published a paper in the Annals of Philosophy on his early experiments with sound, and he developed a “kaleidophone,” in which a bead suspended on the end a steel wire was caused to describe elaborate patterns of movement in harmonic response to different patterns of vibration in the wire. In 1825, he designed a mouth organ whose reeds were controlled by a small keyboard. On June 19, 1829, Wheatstone took out one of his very few patents, on a bellows-driven concertina, which remained a familiar instrument throughout the twentieth century. He also developed a portable harmonium, which won him a prize at the Great Exhibition of 1851.

On the basis of his experiments in acoustics—and his first significant contribution to acoustic theory, published in the Philosophical Transactions of the Royal Society in 1833—Wheatstone was offered the post of professor of experimental philosophy at King’s College in London. This proved to be a crucial career move; as a lecturer, he was a disaster, unable to adapt to public speaking, but he made very productive use of the college’s laboratory facilities, becoming one of Great Britain’s first notable academic research scientists.

Life’s Work

In 1835, Wheatstone read a paper on “The Prismatic Analysis of Electric Light” to the annual meeting of the British Association for the Advancement of Science. The paper paved the way for a means of detecting minute proportions of metals in alloys by the spectroscopic analysis of electric sparks. The method, deployed by other researchers, ultimately revealed the existence of the previously undiscovered metals rubidium and thallium and helped astronomers determine the composition of stars. In 1836, he was elected a fellow of the Royal Society. In 1838, he discovered the principle of stereopsis, or binocular vision, and invented a stereoscope to combine two-dimensional pictorial images so as to give an impression of depth. Wheatstone’s stereoscope, which used mirrors as well as lenses, was subsequently simplified by David Brewster. Wheatstone also invented a “pseudoscope,” which had a contrary effect, making three-dimensional objects seem flat.

Like many other researchers, Wheatstone began experiments in telegraphy when the machine developed by Baron Pavel Schilling was widely demonstrated in 1836. On February 27, 1837, Wheatstone met another researcher in that field, William Fothergill Cooke, and was persuaded to go into partnership with him. Wheatstone, as an academic researcher, had intended to make the results of his own work freely available, but Cooke wanted to make a fortune. When Wheatstone had solved the problem of long-distance transmission, the partners were able to produce their first workable system, patented on June 10, 1837.

The first Cooke-Wheatstone telegraph used five signaling needles to set up sufficient signal combinations to encode the twenty-six letters of the alphabet. They developed a two-needle model in 1838, but it was still too cumbersome to be economically viable. The American inventor Samuel F. B. Morse had been a year behind them in filing his initial patent, but his rapid adoption of a binary code developed in Germany by Carl August von Steinheil enabled him to develop a single-needle system first. It was not until Cooke and Wheatstone began using a single-needle apparatus in 1845 that their system became economically viable. It was then quickly adopted by all the railway companies in Britain. In 1841, however, Cooke and Wheatstone had fallen out over the question of who was primarily responsible for the invention. The matter was referred for arbitration to Sir Marc Isambard Brunel and Professor John Frederic Darnell, whose carefully mediated decision that Wheatstone and Cooke were equally responsible satisfied neither of the contending parties.

The argument between Cooke and Wheatstone flared up again when Cooke set up the Electric Telegraph Company in 1846. A parliamentary commission had to be appointed to sort out various claims for compensation, including one from Alexander Bain. Cooke’s patents were eventually bought by the company for œ120,000, while Wheatstone only received œ33,000; Wheatstone then refused to have anything further to do with the company. The dispute heated up again when Cooke published a combative pamphlet in 1854 entitled The Electric Telegraph: Was It Invented by Professor Wheatstone? Wheatstone’s reply prompted further assertive publications from Cooke.

In the meantime, Wheatstone continued to produce new devices for use in the context of telegraphy. In 1840, he developed a dial telegraph; in 1841, a type-printing telegraph. He also developed an automatic transmitting and receiving system independently of Cooke. Wheatstone became very interested in submarine telegraphy and conducted a significant series of experiments in Swansea Bay in 1844 with the collaboration of J. D. Llewellyn. He also worked in cryptography, developing a cipher that he named for his friend Lord Playfair; the Playfair cipher was still in use by the British army in World War II, although a method for cracking it had been developed earlier in the twentieth century.

Wheatstone’s work in other fields included contributions to the development of the electrical generator, including the combination of armatures so as to produce a continuous current. He developed several devices for managing electrical resistance, including the rheostat. Ironically, the Wheatstone bridge for measuring and balancing electrical currents was only rediscovered by him in 1843, having been invented by Samuel Hunter Christie in 1833. Wheatstone also developed an ingenious method of measuring the velocity of electricity in a wire, using a spark gap and a rotating mirror, but obtained the wrong result, producing a figure in excess of the velocity of light. The “chronoscope” he invented in 1840, which measured minute intervals of time, proved more successful. A “polar clock” he invented for measuring time by the Sun, even when the Sun was obscured by cloud, was of little practical value but was also ingenious.

On February 12, 1847, Wheatstone married Emma West, the daughter of a Taunton tradesman, in Christchurch, Maylebone; they had two sons and three daughters. Although the flow of his inventions abated somewhat thereafter, his reputation continued to grow, especially among fellow scientists who thought that he had been shabbily treated by Cooke. He received honorary doctorates from the universities of Oxford (1862) and Cambridge (1864). He was knighted on January 30, 1868, a year ahead of Cooke. His reputation was international, and he was highly regarded in France. He was appointed a Chevalier of the Legion of Honor in 1855 and became a foreign associate of the French Academy of Sciences in 1873. He was in Paris when he died during an attack of bronchitis in 1875, but his body was shipped home so that he could be buried in Kensal Green Cemetery. Although Cooke made far more money in telegraphy than he did, Wheatstone managed his rewards much more wisely; he left an estate worth œ70,000, while Cooke—like Alexander Bain—died penniless.

Impact

Wheatstone’s achievements were somewhat confused, and perhaps blighted, by disputes over priority. It was inevitable, however, when electrical science was in its infancy and hundreds of researchers were working on the same conspicuous problems, that different researchers would make similar discoveries independently. His reputation outshone those of his detractors in his own day, and most subsequent historians have sided with him for two reasons. First, he was a shining example of zeal and skill in turning scientific theory into practical technology on a prolific and wide-ranging scale. Second, and perhaps more important, he never set out to exploit any of his discoveries commercially with the kind of ruthlessness that William Fothergill Cooke demonstrated; he was interested in discovery for its own sake and was always as ready to lend his work to others as he was to borrow from them. The manner in which he used the opportunities provided by his professorship at King’s College provided an important new model of the raison d’être of academic scientists.

Bibliography

Bowers, Brian. Sir Charles Wheatstone, FRS, 1802-1875. 2d ed. London: Institute of Electrical Engineers, 2001. A reprint of a celebratory biography initially published in 1975, which is undoubtedly the most comprehensive source for information about the man and his works.

Hubbard, Geoffrey. Cooke and Wheatstone and the Invention of the Electric Telegraph. New York: Routledge, 2008. A new edition of a book first published in 1965, which offers a definitive account of the problematic relationship between Wheatstone and his collaborator, and their joint contribution to the development of telegraphy in Britain. The book endeavors to strike a judicious balance in weighing up the two men’s rival claims and is more successful in that regard than most earlier accounts.

Morus, I. R. “’The Nervous System of Britain’: Space, Time and the Electric Telegraph in the Victorian Age.” British Journal of the History of Science 33, no. 4 (2000): 455-476. A comprehensive account of the development of telegraphy in Britain. Better informed and better balanced than Munro but not as broad in its scope.

Munro, John. Heroes of the Telegraph. Whitefish, Mont.: Kessinger, 2004. A new edition of a popular work first published in 1883, which devotes a substantial adulatory chapter to Wheatstone while relegating Cooke’s biography to an appendix, on the grounds that Wheatstone was the partnership’s real “man of science.”

Thompson, Sylvanus P., updated by Brian Bowers. “Sir Charles Wheatstone.” In the Oxford Dictionary of National Biography, edited by H. C. G. Matthew and Brian Harrison. New York: Oxford University Press, 2004. A brief biographical sketch, rather vague by the standards of the DNB because of the relatively light editing of Thompson’s original article.