The student of science fascinated by the mysteries of sound must bring not only his interest put also an excellent ""ear"" to this book which takes up a score of theories about sound and encourages the reader to prove them by experimentation. Methods for measuring frequency are described first. The question of why sound waves do not produce an enormous din of confusion is scientifically explained and then the various media other than air for transmitting sound, the workings of sound molecules, the measuring of its speed, the Doppler Effect (changes in pitch) and the wonders of musical instruments bring us to more complex problems and experiments. These include sounds and electricity, the relationship between sound waves and light waves and the role of mathematics in determining frequencies and pitches. Although a large portion of the materials needed for the experiments can be found around the home, many objects will require a bit of hunting. Only the most proficient will undertake the projects in the latter section.