Experimenting with Time

School Library Journal

Gr 10 Up-Time topics to think about and suggestions for investigating them, especially for enterprising students who have access to high-powered equipment. The subjects range from sundials and star time to body rhythms, global positioning satellites, cesium clocks, and relativity. While some of the suggested projects, such as making a water clock or sundial, are easy (and are presented in greater detail in Marilyn Burns's This Book Is about Time [Little, 1978]), many assume knowledge of algebra (and the willingness to apply it without being handed specific formulae), graphs, or time-lapse photography. Others are simple in concept but call for observations made over months or even a year. Most require that readers do the experiment and trust the results, for few answers are given in this book. What Gardner does provide are clear black-and-white photographs and diagrams; once-over-lightly background explanations with a low, but non-zero, error rate; and lots of questions. The best use of this volume might be as a supplementary text for a physics course. Most young people on their own would be better served by Burns's title, which covers four-fifths of the topics with more corroborative detail and requires less background knowledge.-Margaret Chatham, formerly at Smithtown Library, NY