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and guards the glottis, or orifice of the larynx, by closing down over it, when the act of swallowing takes place. At other times it stands erect, and allows free ingress and egress to the breath. Its depression and its erigation are also the great means of imparting clearness, precision, and force to the initial part of vocal sounds, as may be observed in the energetic utterance of public speaking, by enabling the speaker to compress and suddenly explode the articulate sounds of the voice.
17. At the root of the tongue, lies a small crescent-shaped or horseshoe-formed bone, called, from its resemblance to the Greek letter v, the hyoid, or u-like bone. This member serves, by its firm texture, as a gateway from the trachea and larynx to the mouth, or from the latter to the former. It forms a point of tension for the muscles which connect the larynx with the mouth. Its hard texture enables it to perform this office effectually, and thus to aid in giving pitch to vocal sounds.
18. The thyro-hyoïdean membrane connects the thyroïd cartilage with the instrument just described, and facilitates the functions of both, in elevating or depressing the pitch of the voice.
19. The crico-thyroïd ligament, attaches, as its name implies, the cricoïd to the thyroïd cartilage; and (20.) the cricothyroïd muscle facilitates their consentaneous movement, in the production of vocal sound, acute or grave.
21. The pharynx, or swallow, situated immediately behind the larynx, although not directly concerned in the production of sound, has, - by resonant space, a great effect on its character. Persons in whom this organ is large, have usually a deep-toned voice; those in whom it is small, have comparatively a high pitch. When it is allowed to interfere with the sound of the voice, through negligence of habit, or bad taste, it causes a false and disagreeable guttural swell in the quality of the voice.*
22. The nasal passages. Through these channels the breath is inhaled in the usual tranquil function of breathing. The innermost part of the nostrils, is united into one resonant channel, and opens into the back part of the mouth, behind the " veil," or pendent and movable part, of
*For a full and highly instructive statement of the effect of the pharynx on utterance, see a "Treatise on the Diseases and Hygiène of the Organs of the Voice, by Colombat de l'Isère." Translated by Dr. J. F. W. Lane, and published by Otis, Broaders, & Co. Boston.
the palate, which serves as a curtain to part the nasal arch from the anterior part of the mouth.
23. The internal tubes of the ears. Above the valve of the orifice of the windpipe, on each side of the root of the tongue, is a small opening, leading to a tube which communicates with the ear, and whose orifice is always opened, in the act of opening the mouth. These tubes have a great effect in rendering vocal tone clear and free; as is perceived in the case of obstructions arising from disease, from accident, or from cold, which impart a dull and muffled sound to the voice. "The ear," says an eminent writer on this subject, being formed of very hard bone, and containing the sonorous membrane of the drum, the sound of the voice entering it, through the air-tubes, must necessarily be increased by its passage along what may be termed the whispering galleries of the ear."
The effect of these passages, as conductors of vocal sound, may be traced in the fact, that the middle and innermost parts of the nostrils, open into several hollows, or cells, in the adjacent bones of the face and forehead. By this arrangement, the whole cavity of the head is rendered subservient to the resonance of the voice. That degree of clear, ringing, bell-like sound, which is so obvious a beauty of the human voice, seems to be dependent on this circumstance. Hence, too, the stifled tone caused by obstruction arising from cold, from accident, from the deleterious effect of snuff-taking, or from mal-formation of organic parts.
The fault of utterance which is termed nasal tone, arises from lowering too far the veil of the palate, the membrane which separates the mouth from the nasal passages, and raising too high the root of the tongue, in producing a vocal sound. The consequence of these errors, is, that an undue proportion of breath is forced against the nasal passages, and that these organs are at once overcharged, and obstructed. Hence the forced and false resonance which constitutes "nasal" tone.
24. The cavity, and, more particularly (25) the roof, or ridgy arch, of the mouth, in the anterior part of it, gether with (26) the palate, and (27) the veil, or pendent and movable part of the palate, and (28) the uvula, or the terminating tag of the veil of the palate, in the back part of the mouth, as well as (29) the upper gum, and (30) the teeth, in the fore part of it, all serve important purposes in modifying the sound of the voice, and aiding the function. of speech.
The most satisfactory mode of forming a correct idea of these organs, is, to inspect the interior of the mouth, by the use of a looking-glass. In this way, the position and action of all these parts, in the function of speech, may be distinctly observed.
The mouth, by its form and structure, exerts a great influence in moulding the sound of the voice. It serves at once to give it scope, and partial reverberation. It gives sweetness and smoothness to tone; as we perceive in contrasting the voice duly modified by it, with that which loses its softening effect, in undue nasal ring, or guttural suffoca
To give the voice the full effect of round, smooth, and agreeable tone, the free use of the cavity of the mouth, is indispensable: the whole mouth must be thrown open, by the unimpeded action and movement of the lower jaw. A smothered, imperfect, and lifeless utterance, is the necessary consequence of restraint in the play of this most effective implement of speech. A liberal opening of the mouth, is the only condition on which a free and effective utterance can be produced.
31. The tongue. The various positions and movements of this organ, are the chief means of rendering vocal sound articulate, and thus converting it into speech. They exert, at the same time, a powerful influence on the quality of the voice, by contracting or enlarging the cavity of the mouth, and giving direction to vocal sound: it is the position and action of the root of the tongue, which render the voice guttural, nasal, or oral, in its effect on the ear.
30. The teeth. These instruments, by their hard and sonorous texture, serve to compact and define the volume of the voice, while they aid one of the important purposes of distinct articulation, in the function of speech. Used with exact adaptation to their office, they give a clear and distinct character to enunciation; but, remissly exerted, they cause a course hissing, resembling the sibilation of the inferior animals.
32. The lips. These important aids to articulation, not only give distinctness to utterance, but fulness of effect to the sounds of the voice. Imperfectly used, they produce an obscure mumbling, instead of definite enunciation; and, too slightly parted, they confine the voice within the mouth and throat, instead of giving it free egress and emissive force. In vigorous speech, rightly executed, the lips are
slightly rounded, and even partially, though not boldly, projected. They thus become most effective aids to the definite projection and conveyance of vocal sound: they emit the voice well moulded, and, as it were, exactly aimed at the ear.
Figures 33 and 34 are intended to exhibit the effect of the epiglottis on the character of vocal sound. - When the voice is thrown out with abruptness, or even with a clear, decided force and character of sound, there is first a momentary occlusion of the glottis, attended by the additional effect of the downward pressure of the epiglottis, (the lid of the glottis,) as in the act of swallowing: see figure 33. To this preparatory rallying of the muscular apparatus, and its accompanying effect of resistance, the natural preliminary to a powerful and sudden effort, succeeds an abrupt and instantaneous explosion of breath and sound, produced by the sudden upward impulse of the abdominal muscles and the diaphragm, acting on the pleura, and the air-cells of the lungs, and forcing the breath upward, through the bronchi and the trachea, to the larynx. The breath, thus impelled, bursts forth from the glottis, drives up the epiglottis, (34,) and issues from the mouth, in the form of vocal sound.
Such is the history of the function of vocal explosion,the inseparable characteristic of all impassioned utterance, and, in greater or less degree, accompanying all vivid expression, and all distinct articulation.
FUNCTION OF BREATHING.
THE organs of voice, in common with all other parts of the bodily frame, require the vigor and pliancy of muscle, and the elasticity and animation of nerve, which result from good health, in order to perform their appropriate functions with energy and effect. But these indispensable conditions to the exercise of the vocal organs, are, in the case of most learners, very imperfectly supplied. A sedentary
mode of life, the want of invigorating exercise, close and long continued application of mind, and, perhaps, an impaired state of health, or a feeble constitution, prevent, in many instances, the free and forcible use of those muscles on which voice is dependent. Hence arises the necessity of students of elocution practising physical exercises, adapted to promote general muscular vigor, as a means of attaining energy in vocal functions; the power of any class of muscles, being dependent on the tone of the whole system.
The art of cultivating the voice, however, has, in addition to the various forms of corporeal exercise, practised for the general purpose of promoting health, its own specific prescriptions for securing the vigor of the vocal organs, and modes of exercise adapted to the training of each class of organs separately.
The results of such practice are of indefinite extent : they are limited only by the energy and perseverance of the student, excepting, perhaps, in some instances of imperfect organization. A few weeks of diligent cultivation, are usually sufficient to produce such an effect on the vocal organs, that persons who commence practice, with a feeble and ineffective utterance, attain, in that short period, the full command of clear, forcible, and varied tone.
Gymnastic and calisthenic exercises are invaluable aids to the culture and development of the voice, and should be sedulously practised, when opportunity renders them accessible. But even a slight degree of physical exercise, in any form adapted to the expansion of the chest, and to the freedom and force of the circulation, will serve to impart energy and glow to the muscular apparatus of voice, and clearness to its sound.
There is, therefore, a great advantage in always practising some preliminary muscular actions, as an immediate preparation for vocal exercise. These actions may be selected from the system of preparatory movements, taught at gymnastic establishments; or they may be made to consist in regulated walking, with a view to the acquisition of a firm, easy, and graceful carriage of the body, with appropriate motion of the arms and limbs, in the systematic practice of gesture, in its various forms, for the purpose of obtaining a free, forcible, and effective use of the arm, as a natural accompaniment to speech, or in the practice of attitude and action combined, in the most vivid style of lyric