39K views · 500 reactions | Learn how John Harrison became a world-famous clock maker who helped to solve the problem of finding longitude at sea with the H4 pocket watch. | Royal Museums Greenwich | Facebook

3.1K views · 125 reactions | On this day in 1714, the Longitude Act was passed, which offered rewards for finding an accurate method for navigation at sea. Self-taught clock maker, John Harrison, would go on to take up the challenge. His timepieces, H1, H2, H3 and H4 revolutionised the history of timekeeping. Learn more about the longitude problem: https://bit.ly/longitudeRMG | Royal Museums Greenwich | Facebook