native process which always,
of necessity, accompanies the attentive listening to vocal tones.

Every vocal tone awakens in the hearer a set of imagined muscular
sensations. These sensations furnish the means for an exhaustive
analysis of the operations of the voice. The production of tone
therefore awakens two sets of muscular sensations, one actually felt by
the singer, the other felt in imagination by the listener. The former
are commonly known as the "singer's sensations"; but, as will be
explained later, this expression is often very loosely applied. It is
advisable on this account to give a new name to the singer's sensations,
and also to give a name to the muscular sensations awakened in the
hearer. Let us therefore call the sensations experienced by the singer
in the production of tone the "direct sensations of tone." To the
imaginary sensations of the hearer let us give the name, the
"sympathetic sensations of tone."

These two terms will be used throughout the remainder of this work in
the meanings here given to them.

Direct sensations of tone are the sensations actually felt by the singer
as a result of the exercise of the vocal organs.

Sympathetic sensations of tone are the muscular sensations experienced
in imagination by the hearer as a result of the listening to the tones
of voices other than his own.

CHAPTER II

SYMPATHETIC SENSATIONS OF VOCAL TONE

A peculiar relation of sympathy exists between the human voice and the
human ear. So intimate is this relation that the two might almost be
considered as forming one complete organ. One aspect of this relation
has already been noted, the guidance of the vocal organs by the sense of
hearing. There is now to be considered another feature of this relation
between voice and ear,--the assistance rendered by the vocal organs to
the sense of hearing.

That a sub-conscious adjustment of the vocal organs may supplement the
sense of hearing in the estimation of pitch is mentioned by Prof. Ladd.
Speaking of the ability, by no means uncommon, to tell the pitch of any
musical note heard, Prof. Ladd says: "Such judgment, however, may be,
and ordinarily is, much assisted by auxiliary discriminations of other
sensations which blend with those of the musical tone. Among such
secondary helps the most important are the muscular sensations which
accompany the innervation of the larynx and other organs used in
producing musical tones. For we ordinarily innerv