THE CLOCK

This brief history of time and the instruments used to record it begins with the ancient Babylonians and moves forward to more sophisticated devices. Touching on sundials of ancient Egypt, the Heavenly Clockworks of ancient China, and water clocks of the Dark Ages, it concludes with a fascinating discussion on the development of the clock. The text is at times difficult; for example, the careful but complicated description of the verge escapement, anchor escapement, and level escapement will leave most readers behind. But the author tells a good story, weaving in history, invention, and important personalities like Galileo and Huygens, as well as the lesser known—such as John Harrison, inventor of the chronometric clock. This is the first in the Turning Point Inventions series, which “focus on the important inventions we often take for granted.” Historical photographs are used throughout; they are a handsome, excellent addition to the text. The glossy paper and broad white borders make this an attractive work, though picture captions and index are set in a pale gray Futura type so small that a magnifying lens would be helpful. A promising debut for an elegant new series on inventions for older readers. (Nonfiction. 10-12)