HUGGINS, SIR WILLIAM (1824-191o), English astrono mer, was born in London on Feb. 7, 1824, and was educated at the City of London school and then under private tuition. Having determined to apply himself to the study of astronomy, he built in 1856 a private observatory at Tulse Hill, in the south of London. At first he occupied himself with ordinary routine work, but soon seized eagerly upon the opportunity for novel research offered by Kirchhoff's discoveries in spectrum analysis. The chem ical constitution of the stars was the problem to which he turned his attention, and his first results, obtained in conjunction with Prof. W. A. Miller, were presented to the Royal Society in 1863, in a preliminary note on the "Lines of some of the fixed stars." His experiments, in the same year, on the photographic registra tion of stellar spectra, marked an innovation of a momentous character. But the wet collodion process was then the only one available, and its inconveniences were such as to preclude its extensive employment ; the real triumphs of photographic astron omy began in 1875 with Huggins's adoption and adaptation of the gelatine dry plate which enabled the observer to make exposures of any desired length.
In the last quarter of the 19th century spectroscopy and pho tography together worked a revolution in observational astronomy, and in both branches Huggins acted as pioneer. Many results of great importance are associated with his name. Thus in 1864 the spectroscope yielded him evidence that planetary and irregular nebulae consist of luminous gas. On May 18, 1866, he made the first spectroscopic examination of a temporary star (Nova Coronae), and found it to be enveloped in blazing hydrogen. In 1868 he proved incandescent carbon-vapours to be the main source of cometary light; and in the same year applied Doppler's principle to the detection and measurement of stellar velocities in the line of sight. In solar physics Huggins showed that the form of the prominences could be observed spectroscopically. With Lady Huggins (née Margaret Lindsay Murray, who, after their marriage in 1875, actively assisted her husband) he produced calcium in the laboratory under such conditions that it gave a pair of lines identical with a pair in the solar spectrum whose origin before this had been uncertain. Huggins was made K.C.B. in 1897 and was an original member of the Order of Merit (1902). He was president of the British Association in 1891, and during the years 1900-05, president of the Royal Society, from which he at different times received a Royal, a Copley and a Rumford medal. Four of his presidential addresses were repub lished in 1906, in an illustrated volume entitled The Royal Society. A list of his scientific papers is contained in chapter ii. of the magnificent Atlas of Representative Stellar Spectra, published in 1899, by Sir William and Lady Huggins conjointly, for which they were adjudged the Actonian prize of the Royal Institution. His memoirs in the Philosophical Transactions and other journals were collected in his Scientific Papers, published in 1909. Sir William Huggins died on May 12, 191o. Lady Huggins died on March 24, 1915.