THE LONGITUDE PRIZE

John Harrison, an obscure 18th-century carpenter and clockmaker from Yorkshire, solved a problem that had plagued sailors for centuries: how to tell East-West location at sea, thereby avoiding shipwrecks and other costly disasters. To aid sailors, the British government offered the Longitude Prize, an enormous sum of £20,000 (an amount equal to $12 million today), to the inventor of a device that would determine longitude “that shall have been Tried and found Practicable and useful at Sea.” Harrison met the challenge with his Harrison’s Number One-H-1, the first accurate portable clock. Dash (We Shall Not Be Moved, 1996, etc.) brings the inventor to life with excerpts from his diaries and letters, as she reports on his painstaking experiments, refinements, and extensive sea tests of his 75-pound portable clock. B&w illustraions add a whimsical touch to the telling. For the gruff and meticulous clock-builder, perfecting the clock proved less difficult than claiming the prize offered. Politics and class distinctions in 18th-century England made it extremely difficult for someone not university-educated to get a fair hearing. It took the intervention of His Majesty George III and nearly 50 years of effort before Harrison saw even a portion of his prize money. Dash documents the development of Harrison’s inventions and provides an overview of the politics and science of the period, introducing luminaries such as Sir Isaac Newton and Edmond Halley. Harrison emerges as a stubborn perfectionist who succeeded at long last through great effort. For a less-detailed but perhaps sufficient take on the subject, Trent Duffy’s less-detailed The Clock (p. 630) provides a chapter on Harrison and his chronometric clock. Dash’s title provides an in-depth look at a little known inventor and his life and times and makes good use of primary sources seldom available to students. (afterword, glossary, timeline, bibliography) (Biography. 12-14)