The discovery of the laryngoscope by Garcia enabled him by its means to see
the vocal cords in action and how the reed portion of the vocal instrument
works (_vide_ fig. 9 and description). The chink of the glottis or the
opening between the vocal cords as seen in the mirror of the laryngoscope
varies in size. The vocal cords or ligaments appear dead white and contrast
with the surrounding pink mucous membrane covering the remaining structures
of the larynx. Fig. 10 shows the appearance of the glottis in respiration
and vocalisation. The vocal cords of a man are about seven-twelfths of an
inch in length, and those of a boy (before the voice breaks) or of a woman
are about five-twelfths of an inch; and there is a corresponding difference
in size of the voice-box or larynx. This difference in length of the vocal
cords accounts for the difference in the pitch of the speaking voice and
the register of the singing voice of the two sexes. We should also expect a
constant difference in the length of the cords of a tenor and a bass in the
male, and of the contralto and soprano in the female, but such is not the
case. It is not possible to determine by laryngoscopic examination what is
the natural register of an individual's voice. The vocal cords may be as
long in the tenor as in the bass; this shows what an important part the
resonator plays in the timbre or quality of the voice. Still, it is
generally speaking true, that a small larynx is more often associated with
a higher pitch of voice than a large larynx.

[Illustration: Fig. 10]

[Description: Fig. 10.--Diagram (modified from Aikin) illustrating the
condition of the vocal cords in respiration, whispering, and phonation. (1)
Ordinary breathing; the cords are separated and the windpipe can be seen.
(2) Deep inspiration; the cords are widely separated and a greater extent
of the windpipe is visible. (3) During the whisper the vocal cords are