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sonorous undulations in the open air. In reeded instruments, the reed alone produces and modifies the sound. If the reed be long, the motions are extensive and slow, and consequently the sounds produced are grave: a short reed, on the contrary, produces by necessity acute or sharp sounds, because the alternate transmission and repression of the current of air are more rapid. When we wish to draw from a reeded instrument a variety of sounds, it is necessary to vary the length of the reed; and this accordingly is done by those who play upon the bassoon, clarionet, &c. when they wish to produce different sounds with these instruments. It may be added, however, as an important circumstance, that the elevation of the tone produced by an instrument depends in part on the elasticity, weight, and even the form of the reed, and the intensity of the current of air that plays upon it; for when these circumstances vary, though the length of the reed remains the same, the tone is found to alter very considerably.

The reed is never employed alone, but is always adapted to a tube through which the air passes when it is forced through the reed; and for this reason it is indispensable that the tube be open at both extremities. The tube seems to have no influence whatever on the tone of the sounds, but merely serves to modify their intensity and dis

tinctness. Those tubes which produce the loudest sounds are of a conical form, which enlarge according to their distance from the reed, and their approach to the part where the air escapes. If the cone be reversed, the sound becomes dull; but if two equal cones, opposed base to base, are adjusted to a conical tube, the sound becomes round and strong. Philosophers have not hitherto given any intelligible reason for these modifications.

Only a definite number of determinate sounds can be produced by a column of air, vibrating in a musical tube. It is for this reason that a reeded instrument, when it is long, can only transmit distinctly those sounds which it is intended to produce; and it is also necessary to establish, at first, a certain proportion between the reed and the body of the instrument. When, consequently, we wish to draw a succession of different sounds from the same reeded instrument, it is necessary, not only to modify the length of the reed, but to modify also, in a corresponding manner, the length of the tube. Now this purpose is attained by piercing the sides of the bassoon, clarionet, &c. with small holes. By opening or closing these, we can make the reed and the tube bear such a proportion to each other as may be convenient. By means of the lips, likewise, this agreement enables us more easily to give the instrument the sound which we wish to

produce. This influence of the tube is most remarkable in those instruments which are narrow; so far, indeed, does this go, that the effect produced by the reed is very imperfect, when the tube is not adapted to its capabilities. When the tubes are very large, on the other hand, as in organs, the reeds vibrate almost as freely as in the open air. We cannot, however, tell precisely what are the movements which take place in the air contained in such tubes, when they transmit the sound produced by the reed.

Such, then, are the instruments upon which we shall find that comparisons with the organs of the human voice have been instituted by philosophers. We shall now proceed to these organs themselves.

I.

ORGANS OF THE VOICE.

ACCORDING to principles similar to those which we have just observed in regard to musical instruments, the voice must necessarily depend upon a current of air, with organs to modify it so as to produce sound. The current of air is maintained and influenced by the lungs, and the diaphragm or midriff, with the muscles connected with the ribs and chest; for it is sufficient to the production of sound, that air collected in any receiver, such as the lungs, be driven out in a body with certain force, and that it meets on its passage with vibrators and elastic organs. Fishes accordingly, being deficient in those parts, can utter no sound,-a circumstance which led the celebrated Aristotle to divide animals into vocal and non-vocal.

It is scarcely necessary for us to give a minute description of the lungs, diaphragm, and muscles of the chest, to all which, however, we shall have to advert in considering the disorders and impediments of the voice, and the means of preserving and improving its powers; but, for the present, we shall only describe the immediate organ of the voice.

1. THE LARYNX AND WINDPIPE.

The larynx is a most beautifully constructed organ, fixed upon the top of the windpipe, like a capital upon a pillar, and consisting of a cartilaginous or gristly box, the exterior projection of which is commonly known by the name of Adam's apple, as though it had sprung up in consequence of Adam's eating the forbidden fruit. This projection, however, it may be remarked, is very small, or altogether wanting, in females, and varies also according to age. As the larynx not only produces the sound of the voice, but is also the agent of its principal modifications of tone and pitch, it is indispensable, if we wish to understand the mechanism of the voice thoroughly, to be well and accurately acquainted with its structure and organization. In consequence of not paying a sufficient attention to this point, very imperfect, and even false ideas, have been propagated on this interesting subject. We shall therefore go more particularly into detail upon those parts which are most necessary to be known, and many of which are at present but little understood, even by the learned.

THE BONE AND GRISTLES OF THE LARYNX.

At the root of the tongue lies a small crescentshaped bone, or rather somewhat in the shape of a

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