De La Rue, Warren

(b. Guernsey, 15 January 1815; d. London, England, 19 April 1889)

chemistry, invention, astronomy.

Warren de la Rue was the eldest son of Thomas de la Rue, a printer, and Jane Warren. His early education was at the Collège Sainte-Barbe in Paris. In his teens he entered his father’s printing shop and there first came into contact with science and technology. He was one of the first printers to adopt electrotyping and, with a friend, invented the first envelope-making machine. His understanding of machinery and technology was the basis of his contributions to science. De la Rue was not an original thinker but one who perfected instruments and, through these improvements, made accurate observations of theoretical interest.

De la Rue’s first scientific contributions were to chemistry, in which he remained interested throughout his life. He made a small improvement of the Daniell constant voltage battery that was announced in his first paper (1836). With August Wilhelm Hofmann, the great German teacher of chemistry in London, he edited an English version of the first two volumes of Liebig and Kopp’s Jahresbericht, which served to acquaint English chemists with the work of their Continental colleagues. He was an original member of the Chemical Society, serving as its president in the years 1867–1869 and 1879–1880.

De la Rue’s major contribution was to astronomy. He was drawn to this science by another inventorbusinessman, James Nasmyth, the inventor of the steam pile driver. Nasmyth had been fascinated with the moon for years and had personally drawn some of the best pictures available of our satellite. De la Rue took up astronomy with the purpose of producing more accurate and detailed pictures of the nearby heavenly bodies. He, too, was an excellent draftsman and his drawings of Saturn, the moon, and the sun are superb. His observation of detail was enhanced by improvements he introduced into the polishing and figuring of the thirteen-inch reflecting telescope that he built for his own observatory at Canonbury. His real ability, however, was revealed only when he turned his talents to the application of photography to astronomy. He was able to make stereoscopic plates of the moon’s surface, which brought to light details never before noted. He invented a photoheliographic telescope that permitted the sun’s surface to be mapped photographically. Applying the stereoscopic methods he had used on the moon, he showed in 1861 that sunspots are depressions in the sun’s atmosphere, thus verifying a suggestion made in the eighteenth century by Alexander Wilson of Glasgow.

In later life (1868–1883) De la Rue conducted a series of experiments on electric discharge through gases. They merely multiplied data without leading to any significant theoretical advance.

De la Rue was a fellow of the Royal Society (1850), the Chemical Society, and the Royal Astronomical Society, serving as president of the last-named society from 1864 to 1866. He was also a member and sometime president of the London Institution and member of the Royal Institution and the Royal Microscopical Society.

BIBLIOGRAPHY

De la Rue’s published papers are listed in the Royal Society’s Catalogue of Scientific Papers. The biography that appears in the Dictionary of National Biography is generally reliable, although it tends to exaggerate the importance of his contributions to science, particularly chemistry. His correspondence with Michael Faraday, published in The Selected Correspondence of Michael Faraday, 2 vols. (London, 1971), reveals his methods and abilities, as well as various aspects of his congenial personality.

L. Pearce Williams