Marine timekeeper, H1. This is the first experimental marine timekeeper made by John Harrison in Barrow-on-Humber between 1730 and 1735 as a first step towards solving the longitude problem and winning the great £20,000 prize offered by the British Government. Now known as 'H1', the timekeeper is unaffected by the motion of a ship owing to its two interconnected swinging balances. It compensates for changes in temperature and thanks to extensive anti-friction devices, runs without any lubrication. It was the first relatively successful marine timekeeper of any kind and was the toast of London when Harrison unveiled it in 1735. It is one of the great milestones in clock-making history. See also; ZAA0035 (H2), ZAA0036 (H3) and ZAA0037 (H4).

Object Details

ID: ZAA0034
Collection: Timekeeping
Type: Marine timekeeper
Display location: Display - ROG
Creator: Harrison, John
Places: Greenwich
Date made: 1735
Exhibition: Time and Longitude; Ships, Clocks & Stars: The Quest for Longitude
People: Royal Greenwich Observatory
Credit: National Maritime Museum, Greenwich, London
Measurements: Overall display height: 620 mm, width 680mm, depth 450mm
Parts: H1

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