George III intervenes for Harrison John Harrison produced his fifth marine timekeeper, H5, with the help of his son William. When the Board of Longitude refused to consider H5 alone for a trial, or to accept K1 (a reproduction of H4 manufactured by Larcum Kendall) and H5 as a pair, William contacted King George III for support in overturning the Board’s decision. After H5 was successfully trialled in 1772 at the King’s private observatory at Richmond, the monarch was determined that Harrison should get justice. Despite the King's intervention, the Board insisted on another trial before they could formally reconsider their judgement. In her book, Longitude, science writer Dava Sobel provides a full history of Harrison's dramatic quest to solve the problem of determining longitude at sea. You can also read an account Harrison’s trials and tribulations on Clocktime. Reference Sobel, D. 2011. Longitude: The true story of a lone genius who solved the greatest scientific problem of his time. London: Harper Perennial. Image Credit King George III, studio of Sir William Beechey, oil on canvas, circa 1800, based on a work of 1799–1800. NPG 6250 © National Portrait Gallery, London, CC BY-NC-ND 3.0, https://www.npg.org.uk/collections/search/portrait/mw09368/King-George-III
