Short, James (DNB00)

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SHORT, JAMES (1710–1768), optician, was the son of William Short, a joiner in Edinburgh, where he was born on 10 June 1710. At the age of ten, both parents having died, he was placed in Heriot's Hospital, and, after two years, his talents caused him to be sent to the Edinburgh high school. Here he gained distinction in classics, entered the university of Edinburgh in 1726, and in due course graduated M.A. His relatives aspiring to the ministry for him, he proceeded to the divinity hall, and qualified in 1731 for a preacher in the church of Scotland. Attendance at the mathematical lectures of Colin Maclaurin [q. v.], however, diverted his purpose, never strong. Maclaurin noticed his abilities, permitted him in 1732 to use his college rooms for an optical workshop, and in 1734 informed James Jurin [q. v.]: ‘Mr. Short, who had begun with making glass specula, is now employing himself to improve the metallic. By taking care of the figure he is enabled to give them larger apertures than others have done; and upon the whole, they surpass in perfection all that I have seen of other workmen.’

Short had cleared 500l. by the business when, in 1736, Queen Caroline (1683–1737) [q. v.] summoned him to London to give lessons in mathematics to William Augustus, duke of Cumberland (1721–1765) [q. v.] While in London he effected some improvements in his methods, which he vigorously carried out on his return to Edinburgh, late in the same year. On 24 March 1737 he was elected a fellow of the Royal Society of London, and in 1739 made a survey of the Orkneys for James Douglas, fourteenth earl of Morton [q. v.] He then finally settled in London, but frequently revisited Edinburgh, for the last time in 1766. He died of intestinal mortification at Newington Butts, London, on 14 June 1768, leaving a fortune of 20,000l.

Short was the first to give to specula a true parabolic figure, and the lasting quality of the polish which he imparted to them is proved by the good condition of some which still survive. But, through jealousy of his inventions, he had his tools destroyed before his death. The Gregorian form of construction was almost exclusively employed by him; a Cassegrain, owned at one time by Alexander Aubert [q. v.], formed a well-known exception. His most celebrated instrument was a Gregorian of eighteen inches aperture, completed in 1752 for the king of Spain. The price paid was 1,200l. He made besides several reflectors of twelve-feet focus, for one of which he received from Lord Thomas Spencer in 1743 six hundred guineas. A nine-inch Newtonian by him at Greenwich was remarkable for being no more than eight diameters, or six feet long. It, however, compared unfavourably in performance with William Herschel's seven-foot.

Short made numerous communications to the Royal Society between 1736 and 1763. Several related to his observations of auroras, eclipses, and occultations; others were of greater interest. For an hour near sunrise on 23 Oct. 1740 he viewed Venus attended by a satellite showing an identical phase (Phil. Trans. xli. 646). The illusion is difficult to explain. On 7 Dec. 1749 he described a kind of equatoreal instrument, of which he had constructed three, one bought by Count Bentinck for the prince of Orange (ib. xlvi. 241). He observed the transit of Mercury on 6 May 1753 (ib. xlviii. 192), and the transit of Venus on 6 June 1761 at Savile House, by the command of the Duke of York, who, with several other members of the royal family, was present on the occasion (ib. lii. 178). From a discussion of observations of the same occurrence made in various parts of Europe and at the Cape of Good Hope, Short deduced a solar parallax of 8″.65, long accepted as authoritative (ib. lii. 611, liii. 300). He, moreover, determined the difference of longitude between the observatories of Greenwich and Paris by observations of four transits of Mercury (ib. liii. 158). A sealed paper delivered by him to the Royal Society on 30 April 1752 was opened after his death and read publicly on 25 Jan. 1770. It described a method of working object-lenses to a truly spherical form (ib. lix. 507). His workshop was in Surrey Street, Strand. Besides being versed in mathematics and optics, he was a good general scholar.

[Lord Buchan in Trans. Antiquarian Society of Scotland, 1792, vol. i.; Phil. Trans. abridged (Hutton), xi. 649; Chambers's Biogr. Dict. of Eminent Scotsmen (Thomson); Irving's Book of Scotsmen; Thomson's Hist. of the Royal Society; Gent. Mag. 1768, p. 303; Kitchiner's Practical Observations on Telescopes, 1818, pp. 30, 39–46, including a table of Short's Gregorians from the Nautical Almanac for 1787; Watt's Bibl. Brit.; Hutton's Phil. and Math. Dict. ii. 497.]

A. M. C.