Penguin USA. 10/01/1996. Reprint. In this title the author sets the stage by recounting the difficulties early navigators had in determining their exact longitude. After the loss of many ships and human lives, Parliament in 1714 offered a rich prize for a practical way to measure longitude at sea. John Harrison, an apparently self-taught English clockmaker undertook the task. Over a period of 40 years, he developed four increasingly precise chronometers capable of holding accurate time over a long sea voyage. Comparing the chronometer's time to the local sun time, a navigator could quickly measure the longitude with high precision. With the support of King George III, the clockmaker eventually prevailed and was awarded the prize. Originally published at $13.00 You save 89% off the cover price!

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