Short, James

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SHORT, JAMES

(b. Edinburgh, Scotland, 10 June 1710; d. Stoke Newington, Essex, England, 15 June 1768),

optics.

Short, whose father was an Edinburgh joiner and burgess, was orphaned at the age of ten. He was educated at Heriot’s Hospital, a school for the sons of poor burgesses, and at the Edinburgh High School. In 1726 he entered the University of Edinburgh. His M.A., however, was awarded by the University of St. Andrews in 1753. Because of his excellent academic record, his grandmother hoped that Short would enter the ministry, but he became instead a protégé of Colin Maclaurin, professor of mathematics at Edinburgh. Encouraged by Maclaurin, Short started making mirrors for reflecting telescopes, first of glass, then of speculum metal. His skill in this work received immediate recognition and was the source of these metal mirrors was his lifework, for, unlike other instrument makers of his time, he was a specialist.

Short settled permanently in London in 1738, having been elected a fellow of the Royal Society the previous year. A bachelor, Short’s devotion to his chosen profession, “Optician, solely for reflecting telescopes,” brought him an international reputation and a fortune that was estimated at £20,000 at the time of his death. Short was one of forty-five founder members of the Philosophical Society of Edinburgh; was a founder member, in 1754, of the Society for the Encouragement of Arts, Manufactures and Commerce; and, in 1757, became a foreign member of the Royal Swedish Academy of Sciences.

From 1738 to the end of his life, Short’s home and workshop were in Surrey street, off the Strand. There he made astronomical observations that were frequently reported in the Philosophical Transactions. Short’s portrait, painted by Benjamin Wilson, shows him in his observatory at Surrey Street, overlooking the Thames; behind him is the five-foot-focal-length reflecting telescope that he habitually used.

Short generously encouraged the work of his fellow telescope maker, and potential rival, John Dollond’s experimental work on the correction of chromatic aberration in the refracting telescope. Because of Dollond’s achievement, the refractor was, by the end of Short’s life, beginning to supersede the reflector. Another friend to whom Short gave active support was John Harrison, the chronometer maker. Had Short not championed the notoriously difficult and unpopular Harrison in his disputes with the Board of Longitude, Short might well have become Astronomer Royal. According to Alexander Small, writing to Benjamin Franklin, who was a friend of Short, the help that Short gave to Harrison annoyed the Earl of Morton, who consequently opposed Short’s appointment to the Royal Observatory.

The most reliable source of information about Short’s method of work is the Plymouth physician John Mudge, who visited Short’s workshop and who read two papers to the Royal Society on the founding of metal mirrors for reflecting telescopes. This art was partly in the composition and founding of the metal and partly in the polishing (or figuring) of the mirror. Apparently it was in the latter skill that Short particularly excelled; Mudge wrote of his mirrors, “they are all exquisitely figured.” Recent studies show that Short made a total of 1,370 reflecting telescopes, of which 110 still exist.

The two most important astronomical events of the mid-eighteenth century were the transits of Venus in 1761 and 1769. The purpose of making worldwide observations of the transits was to calculate the solar parallax, and hence to discover the dimensions of the solar system. Astronomers throughout Europe were eager to acquire the best possible instruments for the task. They turned naturally to London, the reputation of whose instrument makers was unrivaled, and, for telescopes, to Short. A week before his death he was still concerned with the despatch of instruments to the Russian Imperial Academy. Short was also, as a mathematician, involved in the calculations of the parallax, and he published two long papers on this problem in the Philosophical Transactions of the Royal Society (1762, 1763). short became a member of the council of the Royal Society in 1760 and was appointed to its special committee set up to study the 1769 transit. He died before he could take an active part in the plans he had helped to formulate, but his instruments were used to observe the second transit from stations throughout the world. Two of his instruments traveled with Cook on the Endeavour to Tahiti.

BIBLIOGRAPHY

I. Original Works. Short’s works include “Description and Uses of the Equatorial Telescope, or Portable Observatory,” in Philosophical Transactions of the Royal Society, 46 (1749–1750), 241–246: “The Observations of the Internal Contact of Venus With the Sun’s Limb, in the Late Transit, Made in Different Places of Europe, Compared With the Time of the Same Contact Observed at the Cape of Good Hope, and the Parallax of the Sun From Thence Determined,” ibid., 52 (1762). 611–628: “The Difference of Longitude Between the Royal Obscervatories of Greenwich and Pairs. Determined by the Observations of the Transits of Mercury Over the Sun in the Years 1723, 1736, 1743, and 1753,” ibid., 53 (1763), 158–169; and “Second Paper Concerning the Parallax of the Sun Determined From the Observations of the Late Transit of Venus: in Which This Subject is Treated of More at Length, and the Quantity of the Parallax More Fully Ascertained,” ibid., 300–345. Short published twenty-eight additional papers in the Philosophical Transactions of the Royal Society, volumes 41 to 59 , most of these being brief accounts of astronomical observations. MS material is in the British Museum Add. MS 4434. Short’s telescopes are housed in museums throughout the world: the Museum of the History of Science. Oxford, holds the longest (twelve-foot focal length) and also seven others.

II. Secondary Literature. See D. J. Bryden. James Short and His Telescopes. Royal Scottish Museum, Edinburgh. July 26t–September 7th. 1968 (Edinburgh 1968): “Note on a Further Portrait of James Short, FRS.” in Notes and Records. Royal Society of London, 24 (1969), 109–112: and “A Portrait Sketch of James Short by the 11th Earl of Buchan,” in Journal of the Royal Society of Arts, 118 (1970). 792; V. L. Chenakal, “Hames Short and Russian Astronomy,” inIstoriko-astronomicheskie issledovaniya, 5 (1959), 11–82; and G. L’E. Turner, “A Portrait of James Short, FRS, Attributed to Benjamin Wilson, FRS,” in Notes and REcords, Royal Society of London, 22 (1967), 105–112; “James Short, FRS, and His Contribution to the Construction of Reflecting Telescopes,” ibid., 24 (1969), 91–108; and “Mr James Short, Optician, Founding Member of the Society,” in Journal of the Royal Society of Arts, 118 (1970), 788–792.

G. L’E. Turner