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power, are but a few of the active agents in the production of the voice. Fifteen pairs attached to the cartilages or os hyoides, are constantly employed as antagonists and directors, and these, when co-operating with those previously mentioned, are susceptible of 17,592,186,044,415 changes ! This is not all; taking into consideration the different degrees of velocity and force with which they are brought into action, varying so materially the quality of the voice, the list of changes would be almost doubled. The facts are not yet told! All the parts that act upon the air, either directly or indirectly, and all the muscles that receive nerves from the respiratory system, are called into action in the production of voice; and when we remember that every movement of the machinery, produces a variation of sound, in some particular, the power of the organs of voice, becomes almost inconceivable. Such, reader, SUCH is the mechanism of an instrument which
"the wealth of Ormus or of Ind,"? could not procure for him who does not possess it, and of which the poorest peasant cannot be deprived, by his relentless creditor.
These organs combine in their construction, the Eolian Harp, and the valvular or key trumpet or common flute; but perhaps as the lungs act as bellows in propelling air through the instrument, some part of it may, with greater propriety, be compared to a church Organ. The wind pipe or trachea, (9) is the tube through which the air passes to and from the lungs in the act of respiration. It is formed chiefly of imperfect rings of cartilage or gristle; the opening behind, however, being closed up with other parts, in order that there may be a perfect tube. These rings being elastic, serve to keep the tube always open, while their flexibility accommodates it to any position of the neck. Some instances are recorded, in which this tube became ossified, viz: changed to bone, in which case, the mode of capital punishment in this country, would not destroy life by strangulation. This is the pipe to the bellows or lungs, and they together constitute the organ part of the vocal apparatus.
The wind pipe is surmounted by a triangular box, of the same material as the tube, the greater prominence of which, in the man, constitutes the difference in the neck of the sexes. This box is called the Larynx, better known to many, by the name of Adam's Apple, from an old story with which every body is familiar, that when Adam attempted to swallow the forbidden fruit, it lodged in his throat, and is thus transmitted to his posterity, as a memorial of his fall. At the upper edge of this box, is attached a bone, in the form of the letter U. It serves to keep the Larynx constantly open, and also for the attachment of several muscles for the contraction and dilatation of this box, which alone is the seat of the voice. Just below the epiglottis, (4) is a simple slit or chink, the diameter of which, is graduated by a number of very delicate muscles, which, together with those tha: increase or diminish the size of the Larynx, answer the exact purpose of the finger holes in the flute.
The base of this instrument is the Cricoid cartilage, (8) so called from its resemblance to a seal-ring, the broad surface of which is visible in the posterior view. The target-like figure on the front part of the thyroid cartilage (6) is intended to represent the Pomum Adami, constituting the boss of the shield. The Epiglottis is a valve which may be seen by depressing the tongue. This beautiful cartilage is attached to the thyroid, the os hyoides and the base of the tongue; it is emphatically a safety valve, for it closes the glottis while in the act of swallowing. How unreasonable for one to suppose that he can talk and eat simultaneously with impunity! The arytenoid cartilages (5-5) and the mechanisin connected with them deserve particular attention. Here we find the mouth-piece or reed of the instrument--the curious ligaments of the rima glottidis or chink of the glottis. On examination, we discover two clefts; the superior one is ten or eleven lines in length, and two or three in width, of a triangular shape. Two folds of the mucous membrane which lines the interior surface of the Larynx, are extended from the arytenoid car. tilages to the epiglottis, and are called the superior vocal cords. A short distance below, is an opening of similar shape, extending from the thyroid cartilage in front, to a muscle which unites the arytenoids. Along the sides of this aperture also, two ligaments are stretched, appositely termed the inferior vocal cords. These delicate harp-strings may be relaxed or made tense by the action of several little muscles, answering the purpose of keys in a violin. Now, in the simplest form of the Eolian harp, fine silken threads are extended upon two bridges, an inch or two above a board, prepared for the purpose. When this is placed in the window frame, with the sash brought down nearly in contact with the strings, the passing breeze causes them to vibrate, producing musical sounds, high, low, soft and loud, in proportion to the tension of the strings, and the action of the air. Here, then, is the Harp part of the instrument. Experiment has conclu. sively shown that these cords and the intervening space, are the essential organs of voice; that previous to the production of a single sound, the chest must be compressed, the glottis adjusted, the larynx elevated or depressed, and the phar. ynx* contracted; that the muscles of expiration act, and the air is propelled into the larynx; that the key-muscles adjust the cords properly, and the air receives the vibrations, whence sound results, and last, though by no means the least important, that volition controls the whole; for, if this were not the case, every contraction of the chest, and consequent expiration of air, would be attended by a sound, as is the action of ill. adjusted machinery.
The larynx is the only organ necessarily employed in singing, and the chief instrument in all natural language; and it is not improbable, that the ruder forms of artificial language were spoken mostly from the throat, as indeed the dialects of the American Indians indicate, for a child will hardly fail to observe that the Aborigines rarely bring the organs of their mouths in contact, in speaking their own languages. For example, take the following names of persons and places: Opecancanough, Onondaga, Yonondio, Kekataugh, Kaihohage. The language of the South Sea 'Islanders abounds so greatly in vocal or glottis sounds, that they can. not pronounce a word loaded with mouth-sounds or consonants. As a specimen, the name of one of their kings may be mentioned: Ta-ma-ha-ma-ka! From a knowledge of these facts, you will more readily understand how an individual might employ artificial language, sing admirably, and still be degtitute of à tòngue; many well authenticated accounts of such instances are recorded, from the earliest age to the present; but it is unnecessary to give them in detail. Deprive man of the larynx, and communities would be bound by a slenderer tie; the song of praise would no longer be wasted on the morning or the evening breeze; the social circle dissolved, man would wander over the earth, distrustful of his fellow; the nobler sentiments of his nature locked up in his own bopom, and the plaint of want unsupplied, the lamentation of analleviated distress, and the exhibition of passion would be his only language.
It was remarked that the inferior vocal cords were essential to the production of voice; by blowing through the wind pipe of an animal, soon after it is slain, you can produce a sound very similar to the natural voice of the animal, if the larynx remains uninjured. Two quadrupeds, the Ant-eater and Pangolin, a kind of lizard, found only in Hindostan, are entirely dumb. Upon examination of the former, it was found that the wind pipe was unusually short, and the upper part of it, the proper region of the larynx, instead of carti. lage or gristle, was a structure of unyielding bone, which sufficiently accounts for the silence of the animal.
CHAPTER X I.
Vocal apparatus of birds-The Mocking bird - Ventriloquism
The voice as indicative of feeling or emotion- Various Illus. trations-Laughing-Whispering-Sighing.
Voice, as we have defined it, is common both to man and the inferior animals, though varying in quality, from the lay of the nightingale to the hiss of the serpent; from the clear melody of the lark, to the discordant shriek of the raven.
A little observation will teach us, that there must be a great difference in the structure of the vocal apparatus in different animals; a difference nearly proportioned to the diversity in the description and quality of the sounds which they are capable of producing. It is from some peculiarity in the formation of the larynx, that the voice owes its quality