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Ever seen a clock that changed the world? We can show you timepieces that are revolutionary - and exquisitely made.
From 14th May until mid-September 2018, the outer case of John Harrison’s fourth timekeeper, H4, will be on loan to the Great Exhibition of the North. Visitors to the Royal Observatory during this period will still have the opportunity to view the original inner movement of H4.
John Harrison's marine timekeepers H1, H2, H3 and H4 are arguably the most important ever made, and you can see them on display at the Royal Observatory Greenwich, in our Time galleries. The clocks are extraordinarily beautiful objects of themselves, as well as being revolutionary in their ability to allow ships to determine their longitude at sea. This development drastically reduced the risk of ships and their crews, along with their precious cargoes, being lost at sea. Harrison was a carpenter by trade and was self-taught in the art of clock making.
Visit the Royal Observatory to discover the work of this unprepossessing man, and how he cracked a problem that had baffled astronomers and mathematicians for centuries. Along with Harrison's celebrated marine timekeepers, including the groundbreaking H4, you can explore displays of scientific objects, paintings and animations exploring the quest for longitude.