waves reflected from the larger. The air is thrown into corresponding
periodic vibrations according to the rate of vibration of the
sound-producing body.

Thirdly, the quality, timbre, or klang depends upon the overtones, in
respect to which I could cite many experiments to prove that whenever a
body vibrates, other bodies near it may be set in vibration, but only on
condition that such bodies shall be capable themselves of producing the
same note. A number of different forms of resonators can be used to
illustrate this law; a law indeed which is of the greatest importance in
connection with the mechanism of the human voice. Although notes are of the
same loudness and pitch when played on different instruments or spoken or
sung by different individuals, yet even a person with no ear for music can
easily detect a difference in the quality of the sound and is able to
recognise the nature of the instrument or the timbre of the voice. This
difference in the timbre is due to harmonics or overtones. Could we but see
the sonorous waves in the air during the transmission of the sound of a
voice, we should see stamped on it the conditions of motion upon which its
characteristic qualities depended; which is due to the fact that every
vocal sound whose vibrations have a complex form can be decomposed into a
series of simple notes all belonging to the harmonic series. These
harmonics or overtones will be considered later when dealing with the
timbre or quality of the human voice.

The vocal instrument is unlike any other musical instrument; it most nearly
approaches a reed instrument. The clarionet and the oboe are examples of
reed instruments, in which the reed does not alter but by means of stops
the length of the column of air in the resonating pipe varies and
determines the pitch of the fundamental note. The organ-pipe with the
vibrating tongue of metal serving as the reed is perhaps the nearest