he ear. This same ability is invoked in the mental
imitation of tones. In one case the muscular contractions are actually
performed; in the other the muscular adjustments are wholly or in part
imaginary.

It is highly probable that actual contractions of the laryngeal muscles
take place, under certain conditions, as an accompaniment to the
listening to voices. This is evident in the case of extremely aggravated
throaty and forced voices. In listening to the harsh, raucous cries of
many street vendors, when calling out their wares, the hearer
frequently feels a sense of actual pain in his own throat.

Involuntary and unconscious contractions of the laryngeal muscles,
somewhat similar to those under consideration, are well known to
experimental psychologists. Prof. Ladd's statement that these
contractions assist the ear in the judgment of absolute pitch has
already been cited. Another example of unconscious laryngeal movements
has been investigated by Hansen and Lehmann ("Ueber unwillkuerliches
Fluestern," _Philos. Studien_, 1895, Vol. XI, p. 47), and by H. S.
Curtis ("Automatic Movements of the Larynx," _Amer. Jour. Psych._, 1900,
Vol. XI, p. 237). The laboratory experiments of these investigators show
that when words, or ideas definitely expressed in words, are strongly
thought but not uttered, the vocal organs unconsciously adjust
themselves to the positions necessary for uttering the words. Curtis
says of these unconscious laryngeal contractions: "Such movements are
very common with normal people, and are comparatively easy of
demonstration."

The apparatus used by Hansen and Lehmann in their experiments consists
of two large concave reflectors. These are placed at a convenient
distance, one facing the other, so that two experimenters may be seated,
the first having his mouth at the focal point of one reflector, the
second with his ear at the focal point of the other. As the first
experimenter repeats mentally any words or phrases, these are found to
be unconsciously whispered. These sounds of whispering, inaudible under
ordinary conditions, are so magnified by the two reflectors as to be
distinctly heard by the second experimenter.

Curtis proved that actual movements of the larynx unconsciously
accompany intense thought. His demonstrations were conducted along lines
familiar to all students of experimental psychology. Similar experiments
would probably show that unconscious movements of the larynx also occur
du