This non-fiction book tells the story of the solution to one of the greatest
engineering problems in recorded history--how to determine
longitude, to find out exactly where in the world one is. Before the solution was found, many ships were lost due to guesswork navigation, and it was the one major obstacle to British supremacy on the high seas. In its day, this problem confounded and befuddled some of the world's most brilliant minds, and a king's ransom in reward money was offered to the man who could solve the problem.
The key to solving the problem was finding a method of keeping time while on a ship at sea, so that the time could be cross-referenced with star sightings to determine an exact position. Carpenter-turned-self-taught-clockmaker John Harrison was determined to solve this problem--and eventually he did, by building an oceangoing clock that kept perfect time, even amid the constant rocking and motion. However, even after solving the problem, it finally required direct intervention by the King of England himself to see the award money dispensed accordingly.
Dava Sobel's book, Longitude, was adapted first as a one-hour Nova presentation by PBS, then as a four-hour A&E miniseries, available on DVD, starring Michael Gambon and Jeremy Irons.
True story: My father, a clockmaker himself, so enjoyed the book that he insisted I look up Sobel's phone number and mailing address in an on-line phone book so he could write directly to her to thank her for writing it.