ally so overhang the glottis that a good
view of the vocal cords is impossible. It is difficult to see more
than one-half to two-thirds of the length of the vocal bands. The
picture seen is that of the parts of the larynx reversed--_i.e._,
while right remains right, posterior becomes anterior. The
laryngoscope shows that (1) in singing an ascending scale the vocal
bands are for a certain time in action (vibration) throughout their
whole length; that (2) there may be observed a rather sudden change
when the vocal bands are relaxed and shortened, and that this process
of shortening goes on, the bands approaching more and more, both
behind and in front, till (3) in the highest tones of a soprano of
great range there is only a small portion of each vocal cord toward
the centre that is not approximated somewhat closely.
With certain qualifications, it may be said that the action of the
vocal bands is alike for all voices. In all cases a certain degree of
approximation of the vocal bands is absolutely necessary for
phonation, and the mechanism is generally similar in males and females
till the highest tones, above alluded to, are reached. This is in
harmony with the following facts: (1) The crico-thyroids are the
muscles most in use in ordinary speech and in singing the lower tones.
(2) Several muscles combine in relaxing and shortening the vocal
bands. (3) The peculiar mechanism of the highest tones in a soprano
voice of great compass is only to be explained by a combined action of
several muscles, and a very delicate and precise use of the internal
thyro-arytenoids attached along the whole length of the outer surface
of the vocal bands. The larynx of the male differs from that of the
female chiefly in its greater size, weight, etc. The vocal bands in
the male may measure from three-fifths to four-fifths of an inch when
relaxed, and from four-fifths to one inch when tense; in the female,
from two-fifths to three-fifths of an inch when relaxed, and from
three-fifths to four-fifths of an inch when tense. There are
structural differences corresponding to and determining the kind of
voice, as to range and power more especially. The bass singer has, as
a rule, the largest larynx and the longest and heaviest vocal bands.
At puberty the changes that take place in the body generally are
associated with corresponding alterations in the larynx. The larynx
grows, changes its proportions, etc., often somewhat rapidly, and the
result
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