THE SCIENCE OF MUSICAL SOUNDS
that each vowel is characterized, not by a single fixed pitch,
but by a fixed region of resonance, which is independent
of the fundamental tone of the vowel; this is the so-called
fixed-pitch theory.
In opposition to this theory, many writers on the sub¬
ject have held that the quality of a vowel, as well as that
of a musical instrument, is characterized by a particular
series of overtones accompanying a given fundamental,
the pitches of the overtones varying with that of the funda¬
mental, so that the ratios remain constant; this is the
relative-pitch theory.
Auerbach in 1876 developed an intermediate theory, con¬
cluding that both characteristics are concerned, and that
the pitch of the most strongly reinforced partial alone is
not sufficient to determine the vowel. Hermann (1889) has
suggested that the vowels might be characterized by partial
tones, the pitches of which are within certain limits, but
which are inharmonic, the partials being independent of the
fundamental. Lloyd (1890) considers that the identity of
a vowel depends not upon the absolute pitch of one or more
resonances, but upon the relative pitches of two or more.
Several quotations will indicate the uncertainty existing
at the present time in regard to the nature of the vowels.
Ellis, the translator of Helmholtz, writes (1885) : “The ex¬
treme divergence of results obtained by investigators shows
the inherent difficulties of the determination.” Lord Ray¬
leigh (1896) says: “A general comparison of his results with
those obtained by other methods has been given by Her¬
mann, from which it will be seen that much remains to be
done before the perplexities involving the subject can be
removed.” Auerbach (1909) discusses the various theories,
but without deciding which is correct.83
216