ne could whistle upon the pockets in the
manner suggested, there are two of them, covered, let it be
remembered, with a multitude of glands, continually producing
moisture, and liable to enlarge or to diminish. How, I should like
to know, could two such cavities be so tuned as under any
circumstances to produce exactly the same tones? Would not rather
frightful discords be the inevitable result? And again, what
provision is there in the pockets for the gradations of pitch? But
quite apart from these considerations, this and other similar
theories are completely disproved by the fact that every tone which
the human voice is capable of producing can be produced by
_inspiration as well as by expiration_. The tones sung by
inspiration are, as might be expected, wholly devoid of beauty,
because the vocal apparatus is, as it were, put upside down, and
the position of bellows and resonator reversed. But that does not
alter the question. The fact remains, and clearly proves that the
pockets have no more to do with the falsetto than with the chest
voice, because in inspiration the air strikes the vocal ligaments
_after it has passed_ the pockets, and yet the result is, beauty of
tone apart, exactly the same.

The function of the pockets, in my opinion, is this: They are the means
of isolating the vocal ligaments, thus enabling them to vibrate freely
and without hindrance. They also allow the sound-waves to expand
sideways, thereby materially adding to their resonance. Lastly, they
with their many little glands produce and supply the vocal ligaments
with that moisture without which, according to the investigations of J.
Mueller,[H] the production of tone cannot be carried on.

Above the pocket ligaments there is a kind of tube which is formed by
the upper part of the pyramids (surmounted by two little bodies called
the cartilages of Santorini, pl. XII, 7, 8) behind; the lid or
epiglottis (pl. XII, 9) in front, and sideways by two folds of mucous
membrane running up from the pyramids to the lid (pl. XII, 14, 10 and
15, 11). These folds are in many cases supported by two small
cartilages, which we will call the Wedges (pl. XII, 12, 13). These,
according to Madame Emma Seiler, are the chief factors in the formation
of the highest register of the female voice. In some physiological works
they are treated as of very little consequence, and