comet of 1868 (Winnecke's) revealed volatilised carbon, which has since proved to be typical of many cometary spectra.
In Feb. 1868 Huggins in the annual report of his observatory to the Royal Astronomical Society referred to experiments he had made in following up suggestions made by (Sir) Norman Lockyer for observing the red flames on prominences in the sun's chromosphere, which had previously been only observed at times of the sun's eclipse. He was not successful in this attempt until the end of the same year, and meanwhile he had been anticipated by Lockyer and Janssen, who saw these prominences immediately after the eclipse in Aug. 1868. Huggins, however, made an essential advance in the method by widening the slit of the spectroscope. About 1862–3 Huggins thought to apply to spectroscopic astronomy the principle enunciated by Doppler in 1841 that the positions of spectrum lines change as the object moves to or from the spectator. After consultation in 1867 with James Clerk Maxwell [q. v.], but wholly independently of him, Huggins presented to the Royal Society early in 1868 some observations on the spectrum of Sirius (Phil. Trans. 1868, clviii. 529), from which a motion of the star from the earth could be deduced of about 25 miles per second. In 1870 the Royal Society came into possession of the Oliveira bequest. This was placed at Huggin's disposal for the construction of a large telescope to enable him to pursue more effectively his researches into the motions of stars. The dome of his observatory was enlarged to a diameter of 18 feet instead of 12, and a new instrument procured from Sir Howard Grubb consisting of a 15-inch refractor and an 18-inch Cassegram reflector, with mirrors of speculum metal which could be used on one mounting. From 1870 to 1875 Huggins used the refracting telescope for determining the velocity of stars in the line of sight by visual observation; the results appeared in the ‘Proceedings of the Royal Society’ in papers ‘On the Spectrum of the Great Nebula in Orion, and on the Motion of Stars towards and from the Earth’ (1872, xx. 379), and ‘On the Motions of some of the Nebulæ towards or from the Earth’ (1874, xxii. 251). Later observers, Vogel, Belopolsky, Frost, Adams, Newall, and Campbell, have greatly developed Huggins's method of this kind of observation with immense advantage to astronomical knowledge. Meanwhile Huggins soon turned his attention with important consequences to the application of photography to stellar spectroscopy. As early as 27 Feb. 1863 he had attempted to photograph the spectrum of Sirius; but the result was unsatisfactory and the effort was not pursued (Phil. Trans. 1864). In 1872 Dr. Draper in America photographed with greater success a spectrum of Vega. In 1876 Huggins secured improved apparatus, and using the gelatine dry-plate, which dates from 1871, he obtained a still better photograph of the spectrum of Vega (cf. Proc. Roy. Soc. 1876, xxv. 445). There followed photographs of great precision of the spectra of the larger stars, of the moon and the planets (cf. ‘On the Photographic Spectra of Stars,’ Phil. Trans. 1880, part ii. p. 669; 1890, xlviii. 216). Applying photography to solar research, he announced to the Royal Society on 21 Dec. 1882, that he had obtained photographs of the solar disc showing also the characteristic rays and structure of the corona round the sun, hitherto seen only during a total solar eclipse. But the promise implied in this communication has not since been realised. ‘The Corona of the Sun’ formed the subject of the Bakerian lecture delivered by Huggins before the Royal Institution on 20 Feb. 1885. In 1882 the photographic method of spectroscopy was applied to the Great Nebula in Orion, and this object was observed again both visually and photographically some years later, mainly to determine the origin of the chief nebular line (cf. Proc. Royal Soc. 1882, xxxiii. 425; 1889, xlvi. 40, with Mrs. Huggins; and 1890, xlviii. 213). On this subject Huggins's conclusions differed from those which (Sir) Norman Lockyer had reached, but finally the observations of Prof. Keeler at the Lick Observatory corroborated Huggins's view that the nebular line is not a remnant of the magnesium fluting and that its origin is still unknown.
Huggins's reputation as an astronomer of the first rank was early recognised. In 1870 he received the degree of hon. LL.D. from Cambridge, and of hon. D.C.L. from Oxford in 1871 (at Lord Salisbury's installation as chancellor). The Universities of Edinburgh, Dublin and St. Andrews all conferred on him the honorary degree of LL.D. From the Royal Society he received the royal medal in 1866, the Rumford in 1880, and the Copley in 1898. The Royal Astronomical Society awarded to him the gold medal for his researches on velocity in the line of sight in 1885. The Paris Academy of Sciences bestowed on him the Lalande prize in 1882,
