Mudge, Thomas

SUBJECT AREA: Horology

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b. 1715 Exeter, England

d. 14 November 1794 Walworth, England

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English clock-and watchmaker who invented the lever escapement that was ultimately used in all mechanical watches.

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Thomas Mudge was the son of a clergyman and schoolmaster who, recognizing his son's mechanical aptitude, apprenticed him to the eminent London clock-and watchmaker George Graham. Mudge became free of the Clockmakers' Company in 1738 and set up on his own account after Graham's death in 1751. Around 1755 he formed a partnership with William Dutton, another apprentice of Graham. The firm produced conventional clocks and watches of excellent quality, but Mudge had also established a reputation for making highly innovative individual pieces. The most significant of these was the watch with a detached-lever escapement that he completed in 1770, although the idea had occurred to him as early as 1754. This watch was purchased by George III for Queen Charlotte and is still in the Royal Collection. Shortly afterwards Mudge moved to Plymouth, to devote his time to the perfection of the marine chronometer, leaving the London business in the hands of Dutton. The chronometers he produced were comparable in performance to those of John Harrison, but like them they were too complicated and expensive to be produced in quantity.

Mudge's patron, Count Bruhl, recognized the potential of the detached-lever escapement, but Mudge was too involved with his marine chronometers to make a watch for him. He did, however, provide Bruhl with a large-scale model of his escapement, from which the Swiss expatriate Josiah Emery was able to make a watch in 1782. Over the next decade Emery made a limited number of similar watches for wealthy clients, and it was the performance of these watches that demonstrated the worth of the escapement. The detached-lever escapement took some time to be adopted universally, but this was facilitated in the nineteenth century by the development of a cheaper form, the pin lever.

By the end of the century the detached-lever escapement was used in one form or another in practically all mechanical watches and portable clocks. If a watch is to be a good timekeeper the balance must be free to swing with as little interference as possible from the escapement. In this respect the cylinder escapement is an improvement on the verge, although it still exerts a frictional force on the balance. The lever escapement is a further improvement because it detaches itself from the balance after delivering the impulse which keeps it oscillating.

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Principal Honours and Distinctions

Clockmaker to George III 1776.

Further Reading

T.Mudge, Jr, 1799, A Description with Plates of the Time-Keeper Invented by the Late Mr. Thomas Mudge, London (contains a tract written by his father and the text of his letters to Count Bruhl).

C.Clutton and G.Daniels, 1986, Watches, 4th edn, London (provides further biographical information and a good account of the history of the lever watch).

R.Good, 1978, Britten's Watch \& Clock Maker's Handbook Dictionary and Guide, 16th edn, London, pp. 190–200 (provides a good technical description of Mudge's lever escapement and its later development).

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