the result? Your tone is raised by a third, or
even more, according to the amount of pressure you exercised on the
shield. And how did this result come about? In this way: By pressing the
shield backwards you elongated the ring-shield muscles, thereby
counteracting their stretching influence, and at the same time
slackening the vocal ligaments. The tone you sang while doing this was,
we will say C'. By releasing the shield you enabled the ring-shield
muscles to contract again, thereby putting the vocal ligaments on the
stretch as they were at first. That changed your C' to E', or higher
still. Have I proved my assertion?

Now one more test, if you please. I pointed out to you on page 34 an
opening between the shield and the ring. You will see it on plate V, No.
10. Please sing a low tone; place your finger gently on the shield, and
move it downwards. You will soon discover a little hollow which
corresponds with the opening I just mentioned, and into which you can
easily put part of the tip of your finger. Now sing up the scale, and
take care to keep the tip of your finger in the hollow. Remember that in
singing up the scale your voicebox will rise, which movement you must
follow, or you will lose the place. If you do this carefully, you will
find that the hollow gets smaller and smaller by degrees until at last
it closes entirely, and you can no longer find a trace of it. Now sing
down again, keeping your finger on the same spot. You will soon notice
the hollow again, and it will continue to get larger and larger until
you arrive at the bottom of your scale.

This, of course, is but another way of showing the mechanism by which
the pitch of your tones is raised or lowered, and we have proved the
same thing by our preceding experiment. But I asked you to try this
chiefly because it will enable you to put a check upon my statements
with regard to the registers of the voice, a subject which I propose to
discuss in another chapter.

THE LARYNGOSCOPE, AND HOW TO USE IT.

The Laryngoscope in its simplest form is a thin circular mirror, about
three-quarters of an inch in diameter, set in a metal frame, and
fastened at an angle of 120 deg. to a piece of wire from three to four
inches long, which is put into a small wooden handle not much thicker
than a pencil, and about the same length as the wire. By help of the
laryngoscope we can either see our own larynx or that of another person.
The easiest experiment is upon