Troughton, Edward

(1753-1835), maker of scientific instruments

by Anita McConnell

© Oxford University Press 2004 All rights reserved

Troughton, Edward (1753-1835), maker of scientific instruments, was born at Corney, Cumberland, probably in October 1753, the youngest of six children of Francis Troughton, farmer and property owner, and his wife, Mary, née Stable. He worked alongside his father, until the death of a brother in London entirely changed the course of his life. Edward's uncle, John Troughton (c.1716-1788), was the first member of the family to enter the London scientific instrument trade; Edward's brother John (c.1739-1807) was trained by him, and John in his turn took a younger brother as apprentice. The death of this brother resulted in Edward's being sent to replace him, and in December 1773 he was bound apprentice for seven years to John. At this time John Troughton worked for other craftsmen, who brought their sextants and small astronomical quadrants to be divided in his workshop, for he enjoyed a high reputation in this difficult art, which was performed entirely by hand. Between 1775 and 1778 John constructed a dividing engine, on the lines of that recently designed by Jesse Ramsden, by which he was able to increase both his accuracy and his rate of work. Edward took a great interest in this art, and set about building his own engine; he also studied astronomy, resolving, as he later said, 'to aim at the nicer parts of my profession'.

John's profits enabled him to acquire property outside London and, in 1782, to purchase the substantial retail business of Benjamin Cole (1725-1813), at the sign of the Orrery, with its shop at 136 Fleet Street and workrooms to the rear. Around 1788 the brothers entered into partnership, trading as John and Edward Troughton until John's death. Edward became a freeman in the Grocers' Company in 1784 and was able to enrol his own apprentices, his nephew Thomas Suddard being among them. These men, when they came to establish their own businesses, were proud to advertise their years with Edward Troughton.

The Troughtons followed Cole in selling a wide range of articles, many of which were made by craftsmen working for the trade, but from the 1780s orders flowed in for large astronomical apparatus to furnish the many private and government observatories then under construction throughout Britain and Europe. The Troughtons' products were of excellent design and construction, and unrivalled in their accuracy; after Ramsden's death in 1800 the brothers were judged by many to be London's finest instrument makers. After John's death in 1807 Edward furnished the Royal Greenwich Observatory with the major new instruments which supplied observations for definitive star catalogues. At least five standard measures of length were prepared, for home and overseas customers. At the same time, Troughton was improving the designs of the common instruments required by surveyors and navigators and 'Troughton' patterns of barometers, sextants, levels, and surveying circles sold in considerable numbers for many years. The smaller astronomical instruments were tested in an observatory which the Troughtons had constructed on the roof of their house. From this vantage point Edward observed and timed the transit of Mercury across the sun's disc in May 1799 and his report was duly published with others in the astronomical literature. Clocks and clock pendulums also captured his interest and he was one of the experts whose opinion was sought on the rival claims of two London chronometer makers.

In 1809 there were plans to replace the antiquated astronomical instruments at the Greenwich observatory with a new free-standing instrument, similar to Ramsden's circle as recently installed at Palermo observatory. When Troughton was consulted, he set down on paper his thoughts about the construction and performance of the various types of circle then in use, and went on to describe a 'mural circle', a new design that he had been considering for some time. This document demonstrates his thorough grasp of the principles of engineering, and of the materials and design strategies that would best serve his purpose. His well-reasoned argument persuaded his prospective customers and construction of this new apparatus was put in hand. There was one problem: the Troughton workshops gave onto a courtyard whose access to Fleet Street was through a low archway too narrow for the passage of bulky goods. It was resolved by Troughton's friend Bryan Donkin (1768-1855), engineer and amateur astronomer. The larger parts of the circle were cast and turned at Donkin's Bermondsey works, a practice which was to be followed for another apparatus. Charles Hafter's oil painting of Troughton with this circle was exhibited at the Royal Academy in 1808 but has since disappeared.

While the mural circle was taking shape Troughton wrote for Nevil Maskelyne (1732-1811), then astronomer royal, a description of his method of dividing by hand, still the only way to divide large circles, a technique which he had hitherto kept secret. His covering letter made it clear that he regarded this disclosure as a valuable present to young craftsmen, and it was certainly accepted as such. The paper was read to the Royal Society and in gratitude for his generosity Troughton was elected a fellow of the society in 1810 and was awarded its Copley medal. Other honours came his way, election to the Society of Civil Engineers, the American Philosophical Society, the Royal Society of Edinburgh, and the Cambridge Philosophical Society. In 1823 he was presented with the freedom and livery of the Clockmakers' Company. He was among the first members of the Astronomical Society, founded in 1820, serving on its council and as vice-president in 1830-31. He was a member of the Astronomical Dining Club, and was welcomed into the houses of the many eminent astronomers who were his customers. In 1824 he travelled to France to stay with James South (1785-1867) at Passy, then spent three weeks in Paris--'perhaps the last frolic of my life'--meeting there, as he engagingly put it, 'many wise men of the south-east'. He contributed articles to Sir David Brewster's Edinburgh Encyclopedia and to other journals. Troughton never married. His friends described him as a modest man, frugal in habit and somewhat careless in dress, who found relaxation in walking and fishing. Reading was the great pleasure of his later years; his library, auctioned by Sothebys after his death, testified to a broad sweep of interests beyond those related to his craft.

By the early 1820s Troughton had come to rely on the support of William Simms (1793-1860) whom he described at that time as one of the best craftsmen known to him. In 1826 he took Simms into partnership; Simms and his wife moved into the Fleet Street house and cared for Troughton in his declining years as he grew more deaf and suffered from rheumatism and lumbago. He nevertheless continued to experiment at his workbench and to converse with customers. As Troughton and Simms the firm undertook the construction of major instruments for George Everest's trigonometrical survey of India and then embarked on Edward Troughton's last project, an equatorial telescope for South. It was an unhappy end to Troughton's distinguished career, for South overruled Troughton on the design and their arguments over this, and the telescope's subsequent disastrous performance, destroyed a long friendship and led to a lengthy court case which was still in progress when Troughton died on 12 June 1835. He was buried at Kensal Green cemetery. Among his bequests were sums to the London Vaccine Institute and St Bride's parish school. The firm of Troughton and Simms continued in the hands of the Simms family, but with no members of the Troughton family being involved.


A. McConnell, Instrument makers to the world: a history of Cooke, Troughton & Simms (1992)
A. W. Skempton and J. Brown, 'John and Edward Troughton', Notes and Records of the Royal Society, 27 (1972-3), 233-62

CUL, Board of Longitude and Board of Visitors MSS
CUL, Greenwich Royal Observatory MSS
Inst. CE, letters to Thomas Telford

C. Hassler, sketch, c.1815
F. Chantrey, bust, 1822, NMM, Greenwich Observatory
F. Chantrey, three pencil sketches, 1822, NPG
Imbert of New York, lithograph (after C. Hassler)
W. Walker and G. Zobel, group portrait, engraving (after J. F. Skill, J. Gilbert, W. and E. Walker, Men of science living in 1807-8), NPG

Oxford University Press 2004 All rights reserved


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