A pleasant, non-technical little book on the physics of sound and music by a Harvard physics instructor. This is just about what the average junior high school student (and his teacher) would like to know about how sounds are made, how they travel, how they are heard, and how musical instruments do their job. Occasional suggestions for simple experiments help to point up the physical principles involved. The line drawings by Joe Krush are just right in their clarity and humor. In format the book looks younger than this age group suggests, but the content would be definitely beyond the younger readers, with a few exceptions.