A look at how his inventions changed timekeeping.
Harrison invented the gridiron pendulum (illustrated here in the background to the right), grasshopper escapement, bi-metallic strip (as you would find in your kettle) and an automatic form of maintaining power, all of which were adopted by later clockmakers and remain evidence of Harrison's enduring contributions to horology. Harrison is possibly best known for the development of a working marine timekeeper, leading to a revolution in navigation by providing a means to calculate longitude at sea.
After John Harrison’s pioneering work, other makers competed to improve and simplify marine chronometers, so putting them into production for the many ships that demanded them. The example here was made by Thomas Earnshaw.
In 1831, Earnshaw’s chronometer was issued to the Beagle for Charles Darwin and Captain Robert Fitzroy’s momentous voyage of discovery to the South Pacific.
This exhibit was curated with assistance from Laura Turner and Oliver Cooke, Curators of the Horological Collections at the British Museum.
You can see the objects depicted here by visiting the British Museum Clocks and Watches galleries, Rooms 38-39.
John Harrison's own marine timekeepers are on display at the Royal Observatory Greenwich, in their Time and Longitude gallery.