John Jefferys (clockmaker)

John Jefferys (1701 – 1754) was an English clockmaker and watchmaker.

His parents, John and Jane Jefferys lived in a house called Darbies in the village of Midgham in the parish of Thatcham in Berkshire. His father was a wool merchant. His maternal grandparents were William and Bridgett Yeats. He had at least five brothers and one sister. Although his father was a Quaker, he was christened on 18 March 1701.

On 4 November 1717 he began an apprenticeship with watchmaker Edward Jagger at Well Close Square, Stepney, London. After nine years of teaching on 26 January 1726 he became a member of the Clockmakers Company of London. In 1735 Larcum Kendall was a new apprentice. Around 1753 he built a pocket watch for watchmaker John Harrison. After he died Larcum Kendall took over his workshop.

John Jefferys watch

The John Jefferys watch that was John Harrison’s personal pocket watch and the prototype for his prize-winning 4th marine timekeeper.

The 22nd October 1707 will always go down in British Naval history as a day which changed the World. It was this foggy day that Admiral Sir Clowdisley Shovell led a British Fleet to disaster on rocks off the Scilly Isles. The tragedy, which cost the lives of 2,000 British Sailors, prompted the Government to offer a £20,000 prize to anyone who could work out how to calculate longitude and therefore a ship’s exact position at sea. The eventual winner, John Harrison was helped in no small way by Midgham man, John Jeffreys.

John Harrison was one of several people trying to find the answer to how to calculate longitude and claim the prize that had been pledged by the Government. After many years and three attempts at making the clock that could be taken to sea without losing time, John eventually came up with the winner. The winning timepiece was not a clock but a pocket watch called H4 made for him in 1753 by our John Jefferys who was then living and working at Holbourn in London. This watch was not only made from designs given to him by John Harrison but in all probabilities had a number of additions and modifications inserted by John Jeffreys himself.

Although not a lot is known about John’s life, he was in fact the son of John Jeffreys a Quaker who lived in Midgham Berkshire during the first half of the 18th century. He was one of five sons, four of whom were born and baptised in Midgham. John junior baptised on the 18th March 1701, William on the 3rd January 1704 and twins Stephen and Benjamin on the 8th March 1705. Regrettably there is no record for a fifth son Samuel, who John junior mentioned in his Will, written in 1744.

John’s father lived in a house in Midgham called Darbies for at least forty years and was still here when John junior died in 1754. Parish records show that in 1738 John Jefferys senior was Overseer of the Poor, although by then John junior had moved to London where he had his watchmaking business.

Unfortunately as John Jefferys junior died in 1754 he never saw the benefit of his creation or the effect it would have on the World. It is also worth noting that although John lived and died in London he still had his connections with Midgham. This is proven in his Will, as he left the inheritance of his freehold land in Midgham (Darbies) to his wife Rebecca, though there is no record of her ever receiving the legacy as his father was still alive so hadn’t inherited the property himself. 

After all these years, let us now acknowledge him as someone who helped change our World and therefore certainly an individual who should be documented as one of the greatest unsung hero’s of Midgham.

In 1739, a family friend and fellow Midgham resident fourteen-year-old Jethro Tull, son of Richard Tull of Button Court, was apprenticed to John Jeffreys in London to learn the skills and art of the Clockmaker. This Jethro Tull although living in Midgham later started his own clock and watchmaking business in Newbury. Watches made by him can be seen at Newbury Museum.


You can find out more about the relationship between Jeffreys and Harrison by reading…

Longitude: The True Story of a Lone Genius Who Solved the Greatest Scientific Problem of His Time


“A story every nautical navigator should know”

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