Following one of the most inspiring and fascinating stories linked to the Royal Observatory, Greenwich, this book centres on the life and achievements of John Harrison - designer and builder of the first accurate marine chronometers. Inspired by the official prize offered in 1714 to anyone who could solve the problem of finding longitudinal position at sea, Harrison produced his four famous 'H' timepieces. In doing so, he helped revolutionise sea travel, saving many thousands of lives. John Harrison and the Quest for Longitude is the intriguing account of one man driven by the need to solve one of the greatest practical problems of his time.