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CHAPTER II

THE VOCAL APPARATUS

In undertaking to improve the use of the voice, it is desirable to know at the outset something about the mechanism which produces speech. Briefly stated the vocal apparatus comprises four parts: the breathing organs, the voice-box (larynx), the resonance cavities, and the organs of articulation.

The breathing apparatus includes the lungs, opening out through the mouth and nose passages; the muscles which control the framework enclosing the lungs; the diaphragm, upon which the lungs rest; and the abdominal muscles, which assist the operation of the diaphragm in the breathing process.

The voice-box is hinged to the top of the windpipe (trachea) and consists of five pieces of cartilage. The lower piece is shaped like a signet ring. Fastened to the top of the broad part at a slight distance apart are two more small pieces. To these are joined two small bands of tough elastic fiber which form the inside edges of the two half discs stretching over the ring cartilage. These bands (the vocal cords) are joined in front to two shield-shaped cartilages, which form the enclosing walls of the voice-box. The space between the vocal bands is called the glottis. Between the root of the tongue and the voice-box is a thin layer of cartilage called the epiglottis, which closes over the top of the

voice-box during the swallowing process, thus directing all substances into the gullet behind it. To all these cartilages are attached various muscles which raise, lower, and tip the entire voice-box, open and shut the epiglottis, tighten and relax the vocal bands, and narrow and widen the glottis.

The fundamental sound of the voice is produced by puffs of breath passing through the glottis and setting up vibrations of the vocal bands. If the bands are sufficiently relaxed and separated, as in ordinary breathing, no sound ensues. When the bands are tightened and brought closer together, vocalization begins. The closer and tighter they are drawn, the higher the tone will be; the stronger the current of breath becomes, the louder will be the resultant tone.

But the fundamental tone produced in the voice-box is not the sound which is actually heard. Before it reaches the listener it has been greatly strengthened and improved by the third factor mentioned at the beginning of this chapter, the resonance cavities. The most important of these are: the pharynx, that muscle-lined cavity above the voice-box and commonly known as the back part of the mouth or upper part of the throat; the mouth proper; the two nasal cavities, extending from the roof of the mouth to the base of the skull; and the four small cavities (sinuses) in the lower part of the skull.

These numerous cavities are the chambers in which vibrate the sound waves set up by the fundamental vibrations in the voice-box. They correspond to the brass tubing of a horn, the pipes of an organ, or the hollow body of a violin. The chief reason why so many voices are" thin," or "flat," "harsh," or "nasal" is

not that there are so many defective organs, but that people so often fail to utilize their resonance cavities to advantage. This matter we shall consider when the subject of voice quality is discussed. Our more immediate concern is with the fact that two of the resonance cavities, the pharynx and the mouth, are capable of various changes in size and shape through the raising and lowering of the larynx, the shifting of the tongue and soft palate, and the operating of the muscles of the pharynx and jaws. To these changes, mainly, is due the remarkable variety of vowel sounds.

The last factor of speech mechanism is the apparatus of articulation. It is by articulating, or joining, in various ways, two or more organs of the mouth that the consonant sounds are made possible. The organs of articulation are as follows: the hard palate, which roofs the front half of the mouth; the tongue, whose parts will be subsequently designated as back, blade (middle section), and tip; the teeth; the lips; and the soft palate, which forms an arching partition between the mouth and the nasal cavities above. This partition can be lowered so as to direct the breath current through the nasal passages, as in the case of the m, n, or ng sounds; or it can be raised so as to direct the breath out through the mouth, as in the case of h. For the majority of consonants, it is arched sufficiently to direct most of the breath out through the mouth.

Having in mind the chief mechanical factors by which the speech sounds are produced, we shall now proceed to examine in some detail the proper operation of the vocal apparatus.

CHAPTER III

BREATHING

The vocal organ is a wind instrument, essentially like the oboe and bassoon, with respect to sound production. Just as the tones of these two instruments are obtained by forcing between two reeds a stream of air, so vocal tones depend upon breath being sent out between the vocal bands. Breath is the fundamental factor of voice; therefore a careful consideration of its proper management is essential. Good speaking requires that we breathe correctly, that we utilize our lung capacity, and that we gain full control of the breath supply.

First, it is to be observed that the capacity of the lungs is less in the upper than in the middle and lower sections. Next, we should note that the lungs are surrounded by a framework consisting of the spinal column in the rear, the twelve ribs around each side, and the breast-bone (sternum) to which the upper ten pairs of ribs are joined in front. Numerous muscles attached to this framework permit an upward forward movement of the sternum and ribs, thus inducing a horizontal expansion of the lungs. Furthermore, a longitudinal expansion is made possible by the proper use of the diaphragm. This organ is a broad, dome-shaped muscle, attached at the front, sides, and back to the sternum, lower ribs, and spinal-column respectively. Resting on top of the diaphragm are the lungs; below is the upper abdomen.

By depressing the dome of the diaphragm upon the yielding organs beneath, the lower masses of lung cells are enabled to expand downward, thus adding greatly to the breath capacity.

The actions just discussed, i. e., the distention of the framework and the lowering of the diaphragm, occur to some extent in ordinary inhalation. The process is noticeable at any time but may be most clearly observed in the case of a person lying on his back and breathing normally. The chest rises and the waist expands with inhalation, and both sink with exhalation.

Now when speaking, many people, owing to nervousness or mistaken ideas about breathing, fail to make proper use of the breathing apparatus. One common mistake is to lift the shoulders at inhalation. This action not only tends to restrict the breath to the relatively few cells at the top of the lungs, but also by causing pressure upon the flexible organs in the throat hinders the free passage of air, thus reducing vocal power and producing dryness and soreness of the membranes. Another error is to draw in the waist line and hold up the diaphragm during inhalation, thus interfering with the expansion of the lower lung cells.

Not only should we avoid these abnormal actions but we should also develop our breathing power for speech purposes. At inhalation the dome of the diaphragm should be so depressed as to cause a noticeable distention in the whole region of the waist. This can be readily sensed by placing the thumbs just above the hips and spreading the fingers forward over the abdomen. At the same time the chest should be raised and expanded. The effect of depressing the diaphragm and raising the chest is to increase greatly the capacity of the thoracic

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