John Jefferys (1701 – 1754) was an English clockmaker and watchmaker.
[1] His parents, John and Jane Jefferys lived in a house called Darbies in the village of Midgham in the parish of Thatcham in Berkshire.
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.
Actor Peter-Hugo Daly was cast as John Jefferys in the Channel 4 TV series, Longitude in 2000.