In the 18th century, ships at sea could not accurately determine their east-west position, or longitude. The marine timekeeper crafted by clockmaker John Harrison is credited with solving this difficult problem. We compare the famous story of a single genius overcoming a hostile board with materials from museums and parliamentary history.
What we found: Harrison’s fourth timekeeper was recognized by the Board of Longitude in 1765 as having kept time within the legal standard. However, the 1714 Longitude Act stemmed from the efforts of mathematicians, and the Board began funding development in 1737. Kendall’s copy was relied upon during Cook’s voyages, while Maskelyne’s lunar tables were used alongside it. It took decades for marine timekeepers to become widespread. Harrison received 10,000 pounds in 1765 and 8,750 pounds from Parliament in 1773, rather than the exact prize set by the 1714 Act. Assessments of whether the Board treated him fairly remain divided.
Content type: Fact (reconstruction based on records). Visuals are reconstructions and explanatory diagrams built in Minecraft, not actual archival footage or original 18th-century ships and timekeepers. Map and model scales as well as character movements are expressions for explanatory purposes.
In the series “Crossroads of Sea Routes and Daily Life”, we trace the “whys” of navigation and trade through historical records. Going beyond mere results, this helps you understand the choices and constraints of the time and read how the world changed.