HERSCHEL, Sit John Frederick Wild ham, English astronomer • only son of Sir Wil liam Herschel (q.v.) : b. Slough, near Windsor, 7 March 1792; d Collingwood, Kent, 1I May 1871. He was educated at Eton and Cambridge. His first publication was 'A Collection of Ex amples of the. Application of the Calculus to Finite Differences' (1820). but it was not until the death of his father that he devoted his special attention to those astronomical researches which have made the name of Herschel, so famous. He limited'his firsf exertions to a re examination.of the nebula and clusters of stars discovered by his father, and in 1824, with James South, reported 'CI) the Royal Society the posi tion and apparent distances of 380 double and triple stars, obtained by more than 10,000 meas urements. This memoir attracted the notice of the French Academy, and they voted it their astronomical prize; and two years later the gold medal of the Royal Society was awarded to each of the astronomers. The results of the re-examination were given in 1833 to the Royal Society in the form of a catalogue of stars in order of their right ascension. The catalogue contained observations on '525 nebula and clusters of stars not noticed by his father, and on a great number of double stars, be tween 3,000 and 4,000 in all. His 'Treatise on the Theory of Light' appeared in 1827; that on in 1830, and in the same year was published his well-known 'Preliminary Dis course on the Study of Natural Philosophy;' one of the most charmingly written books on science. In 1831 he was created a knight of the Royal Hanoverian Order. In 1833 Herl schel published in Lardfter's 'Cabinet Cyclo pedia) a 'Treatise on Astronomy,' subse quently enlarged into 'The Outlines of Astron omye of which several editions have been published. 'In the same year he undertook a
private expedition to the Cape of Good Hope for the purpose of carrying out in the southern hemisphere observations similar to those he had made in the northern. Four years were spent near Cape Town (1834-37). His great Object was to discover whether the distribution of the • stars in the southern hemisphere cor responded with the results of his father's labors, prosecuted mainly on the opposite side of the Galactic Circle. That the observations -might be strictly comparable they were made by the same method as Sir W. Herschel, and with a telescope of the same optical power, The Whole number of stars counted in the telescope amounted to 68,948, included within 2,299 fields of view. By a computation based on the star-, gauges in both hemispheres relative to the Milky Way, Sir John found that the stars Visible in a reflecting telescope of 18 inches aperture amounted to 5,331,572; and more than this, the number really visible in the telescope was vastly greater, for in some parts of the Milky Way the stars were found to be so crowded in space as to defy all attempts to count them. The results of this vast labor were published in 1847. On Herschel's return to England in 1838 he, was received with every public honor, and on the !queen's coronation was created a baronet. He was buried in Westminster ,Abbey.