Fig. 344.—The human ear.

The tones produced by men are lower than those of women and boys. In men the vocal cords are about 18 mm. long; in women they are 12 mm. long.

The compass of the human voice is about two octaves, although some noted singers have a range of two and one-half octaves. In ordinary conversation the wave length of sounds produced by a man's voice is from 8 to 12 ft. and that of a woman's voice is from 2 to 4 ft.

Important Topics

1. Tone quality. Fundamental and overtones. Chladni's plate.

2. Manometric flame apparatus.

3. Phonograph recorder and reproducer.

4. Air columns and wind instruments.

5. How we hear.

Exercises