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THE ORGANS OF VOICE..
A LABORED and minute description of the organs of the human voice, would be incompatible with the design of a brief and practical work, such as this. Nor is an exact anatomical knowledge of these parts of the human frame, or a profound investigation of the physiology of their functions, essential to the purposes of culture. All that is aimed at, in the following observations, is, to impart such an idea of organic structure and action, as is indispensable to an intelligent, voluntary use of the vocal organs.
To examine the corporeal mechanism of speech, we commence with a survey of the trunk of the body, the great cavity, or main pipe, of vocal sound, and the seat of the principal apparatus whose motions give origin to voice. As the first step in our investigation, then, we wish to withdraw the student's attention entirely from the tongue, the mouth, and the throat, - the immediate, and, as it were, conscious instruments of utterance, and to fasten the thoughts on the sources of voice, — the unconscious, and, in part, the involuntary, action of the muscles which enlarge and compress the cavity of the organic frame, and render it a resonant body.
The production of vocal sound, is, to a certain extent, identical with the function of breathing. A person in health, and free from pain, breathes without any perceptible sound, but that gentle whispering effect which is produced by inspiration and expiration, drawing in and giving forth the breath. We observe this process exemplified in the tranquil breathing of one who is reading silently. But let the reader come to a passage of intense interest and exciting
- Ic facilitate the use of this manual in practical instruction, subjects which aemand the attention of adult students principally, are transferred to the appendix of this edition. Individuals who can comma
mand the regu portunities of acquiring actual information concerning the structure of the vocal organs, would do well to attend anatomical dissections, and particularly post mortem examinations of the parts; as the tendency of the membranous lining of the organic apparatus to shrink, when cold, and to shrivel, when dry, does not easily admit of a true exhibition, - either in mannikin models, anatomical preparations, or engraved illustrations, — of the most important of all the instruments of phonation, — the surface of the vocal ligaments. M. Colombat de l'Isère, in his work on the hygiène and diseases of the voice, indicates the not uncommon errors, even of professional men, on this point.
emotion; and the breathing becomes, in consequence of the heightened organic action, caused by excessive feeling, hard and laborious : its force renders it plainly audible. A sigh, a sob, or a partial groan, perhaps, follows as the result of the over-excited action of the breathing apparatus. Breath thus becomes sound. We have here the history of involuntary voice.
A parallel illustration might be drawn from the hard breathing, the suppressed or loud groans, and the articulate exclamations, of a person suffering through the various stages of pain, from uneasiness to agony. But it is unnecessary to pursue examples of the fact that the function of breathing, when rendered intense, becomes vocal. To analyze the human voice, therefore, or to trace the organic mechanism of speech, we must examine the apparatus employed in the act of breathing.
We commence our investigation with the primary action of inspiration, or inhaling breath. A person in good health, draws in breath by an exertion, partly involuntary, partly voluntary, of those muscles which, by a combined act, expand, and, at the same time, raise the chest, and consequently enlarge the cavity called the thorax, — the region between the neck and the stomach. The degree of freedom and energy, in this muscular action, decides, of course, the extent to which the thoracic cavity is enlarged, and the volume of air which is inhaled : it decides also, as a natural consequence, the capacity of resonance in the chest, and the fulness of the supply of breath, the material of sound.
These preliminary facts teach us the first practical lesson in the cultivation of the voice, - the necessity of maintaining an erect, free, expansive, unembarrassed, posture of the chest, as an indispensable condition of full, clear, distinct, effective, and appropriate utterance.
Continuing our investigation of voice, we return, for a moment, to the case of a person in the act of silent reading. Let the reader come to a passage, not of exciting effect or vivid emotion, but of profound and absorbing thought, which fixes the attention, with extreme earnestness, on an abstruse subject, rivets the mind on a single point, requiring the closest discrimination, or leads it away in a train of abstract thought: let there be, in one word, what we term a “breathless " attention ; and we observe the person at once in the situation which we designate by the common phrase, “ holding the breath." The reader, so situated, neither attempts to inhale a fresh breath, nor to let go that which he has inhaled ; his chest becomes, as it were, fixed and immovable; in the intensity of his attention to a mental object, he forgets and neglects the organic demands of the vital processes; he unconsciously sympathizes with the stimulated condition of his brain ; and his nervous energy takes that direction, — to the suspension, almost, of the functions of breathing, and even of circulation, and digestion, – hence the enfeebled state of the lungs, the paleness of the countenance, and the coldness of the extremities, which attend close mental application, when intense or long continued. Such is the condition of the human being, under the spell of
the intellectual instincts, when nature is absorbing the powers of life, for the purposes of fixed thought, and is forbidding utterance, or expression, or any external manifestation of mind. Voice is, in such circumstances, silenced; and the organs are, for the time, irrevocably closed, by the stricture which is thrown over them.
But let us continue our observation of this silent reader; and we may perceive, perhaps, an immediate and entire change of phenomena. "The spell of irresistible attraction in the page of the book, has ceased; the cloud of perplexity has passed away; the difficulty is solved; the discrimination is made ; the doubt is cleared up; or the train of thought is come to an issue. As a consequence, the rigor of the brow relaxes ; a radiant smile takes its place; the suspended breathing is resumed, with a deep and full expiration, which seems to let go the imprisoned function; the returning blood restores its hue to the cheek and the lip; animation once more sparkles in the eye; the heart resumes the throb of life ; and a genial glow is diffused over the whole frame; an exclamation of joy, perhaps, succeeds; and a friend standing near, is invited, in cheerful accents, to partake the intellectual pleasure of the reader. The effect on the organs of speech, in such circumstances, is, then, that the breath is no longer held: the struggling prisoner escapes in a sigh of instinctive, reactive effort, or in an exclamation of delight.
The practical lesson here taught, is, that utterance demands a free expulsion, not less than a deep inhalation of breath ; – that there must be a vigorous consentaneous action of the will, along with the silent involuntary process of nature.
The full function of expiration, when carried to the extent of exclamation, as in the case supposed, implies an energetic use of the lower muscles of the trunk, — those which are termed the abdominal,' — to impart, by upward and inward impulse, a powerful percussion to the diaphragm, by which the breath contained in the air-cells of the lungs, is forced through the bronchial tubes and the trachea, towards the glottis and the larynx, where it is converted into sound, and thence into and through the mouth, and the cavity of the head, where it is modified into speech, by the action of the nasal passage, the tongue, the palate, the teeth, and the lips, in the various functions of articulate utterance.
The engraved figures will serve to impart a clearer idea than can be conveyed by words, of the place and form of the vocal organs, together with their action in the production of sound.
Figure 1 represents the principal abdominal muscle, by which the first expulsory movement terminating in sound, is produced. The action of this muscle, in energetic and abrupt forms of utterance, is nearly the same in kind, though not in degree, with that which takes place in the sudden shrinking from a blow, aimed at or below the
1 In shouting and calling, and other violent exertions of voice, the dorsal muscles, - those of the lower part of the back, - partake in the expulsory eftort.
stomach. In vigorous utterance of a steady and sustained character, or in the energetic singing of long notes, a powerful and continued upward and inward pressure of the abdominal muscles, takes place, as in the attitude observed in swift riding on horseback.
2. The diaphragm, which by an upward impulse, consentaneous with that of the abdominal muscles, and imparted to the pleura, or enveloping membrane of the lungs, forces the breath from the aircells into the bronchi, and thence into the trachea and the larynx.
3. The thorar, the great cavity of the chest. By the expansion and compression of this capacious organ, the process of breathing is conducted; and by its resonance, the voice receives depth and volume,
4. The intercostal muscles at the lower, and
5. The thoracic and pectoral muscles, at the upper part of the chest, serve to dilate and compress ii, in the acts of breathing and of utterance.
6. The pleura, a membrane which envelopes the lungs, and propagates to their cells the impulse by which these are emptied of their successive supplies of air inhaled at the intervals of speaking or singing.
7. The lungs, a spongy body, in the form of lobes, into the cells, or little cavities, of which, the air inhaled in breathing, is drawn, and from which it is expelled by the impulse communicated, as mentioned before, by the pleura, and derived from the diaphragm and the abdominal muscles.
8. The bronchi, or two main branches of the trachea, or windpipe. These two tubes are themselves subdivided into many subordinate and minute ramifications, which serve to distribute to the air-cells of the lungs, — in which they terminate, - the breath inhaled through the trachea, and to convey that which is expelled from the lungs, by the impulsive action of the diaphragm, into the trachea, the larynx and the mouth. One important office of the bronchial ramifications, is to vibrate, and thereby aid in rendering vocal the column of air which is emitted from the cells of the lungs.
9. The trachea, or wind-pipe, a series of connected cartilaginous, or gristly, rings, forming the great air-tube, which receives and conducts the breath to and from the lungs, in the acts of inspiration and expiration, and in the function of utterance.
10. The larynx, a cartilaginous box, on the top of the trachea, the exterior projection of which is familiarly called the Adam's apple, in allusion to the fabled origin of this part, which was anciently said to have owed its existence to Adam's fatal offence in swallowing the forbidden fruit. The whole larynx is the immediate seat and general instrument of vocal sound. The portions of this organ, which are immediately concerned in the production of sound, are, . .
11. The cricoid cartilage, situated immediately over the uppermost ring of the trachea, resembling, in form, a seal-ring, from which it takes its name, but having the broad part at the back, and the narrow in front. The form and position of this portion of the larynx, admit of the elevation and depression of its parts, — one step in the process by which tone is rendered grave or acute.