guardian1 Clockmaker John Harrison vindicated 250 years after ‘absurd’ claims 58ths of a second over 100 day accuracy is proven with Harrison's design in April of 2015. guardian2 A true sea shanty: the story behind the Longitude prize independant John Harrison's 'longitude' clock sets new record - 300 years on

longitude Longitude Three hours. Superb. nova Nova one hour video on Harrison. revolution Revolution in time Clocks and the Making of the Modern World, Revised and Enlarged Edition David S. Landes