CLOCKS AND HOW THEY GO

Instead of taking clocks apart, or maybe in conjunction, the youngest investigators might turn to Gibbons' simple explanation of their mechanisms. Gibbons gets across the principles of weights and springs and the function of the gears (not so named, though ""escapement"" is)--which will do for a start, though some likely questions are left unanswered. Her plain, bright-colored pictures are generally clear as far as they go, though an occasional label would be helpful. Best used with adult backup, for readers too young for Johnson's What Makes a Clock Tick (1970).