One of the most extraordinary instances of this last kind consists in the art of what is called VENTRILOQUISM, of which no very plausible explanation has hitherto been offered to the world. The practitioner of this occult art is well known to have a power of modifying his voice in such a manner as to imitate the voices of different persons conversing at some distance from each other, and in very different tones. And hence the first impression which this ingenious trick or exhibition produced on the world, was that of the artist's possessing a double or triple larynx, the additional larynxes being supposed to be seated still deeper in the chest than the lowermost of the two that belong to birds; whence, indeed, the name of  VENTRILOQUISM or BELLY-SPEAKING. This rude and early idea M. Richerand was at one time strongly tempted to revive; but a closer examination of the subject convinced him that it could not be supported, and he abandoned it, without however offering any other sufficiently  natural for examination. Mr. Gough has attempted, in the Memoirs of the Manchester Society, to resolve the whole into the phenomenon of echoes; the ventriloquist, on this hypothesis, being conceived to confine himself on all occasions to a room well-disposed for echoes in various parts of it, and merely to produce false voices by directing his natural voice in a straight line towards such echoing parts, instead of in a straight line towards the audience; who, upon this view of the subject, are supposed to be artfully placed on one or both sides of the ventriloquist. It is sufficient, in opposition to this conjecture, to observe that it does not account for the perfect quiescence of the mouth and cheeks of the performer wile employing his feigned voices; and that an adept in the art, like M. Fitzjames, who exhibited a few years ago in our own country, or M. Alexandre of the present day, is totally indifferent to the room in which he practises, and will readily allow another person to chuse a room for him. Of M. Fitzjames, M. Richerand has given a particular account form personal examination. He observes, that he always made a strong inspiration before he commenced his performance, and could support his various voices till he required a fresh supply of air, thus evidently proving that the inhaled air was expired, though not through the lips, but, as appears from another case observed by M. Richerand, at least partly through the nostrils. 

Yet the means by which the ventriloquist is enabled to modify his articulations into the semblance of distinct voices, still remains to be explained; and I shall hence beg leave to throw out a suggestion upon the subject. From various concurrent facts, ventriloquism appears to be an imitative art, founded on a close attention to the almost infinite variety of tones, articulations, and inflexions which the glottis is capable of producing in its own region alone, when long and dextrously practisd upon; and a skilful modification of these vocal sounds, thus limited to the glottis, into mimic speech, passed for the most part, and whenever necessary, through the cavity of the nostrils, instead of through the mouth.. It is possible, however, though no opportunity has hitherto occurred of proving the fact by dissection, that those who learn the art with facility, and carry it to perfection, possess some peculiarity in the structure of the glottis, and particularly in respect to its muscles or cartilages.

In singing, everyone knows that the glottis is the only organ made use of, except where the tones are not merely uttered, but articulated. It is the only organ employed, as already observed, in the mock articulations of parrots, and other imitative birds; it is the only organ of natural cries, constituting the language of all animals possessing a voice; and hence Lord Monboddo has ingeniously conjectured that it is the chief organ of articulate language, in its rudest and most barbaric style. "As all natural cries," says he, "even though modulated by music, are from the throat and larynx, or knot of the throat, with little or no operation of the organs of the mouth, it is natural to suppose that the first languages were, for the greater part, spoken from the throat; and that what consonants were used to vary the cries, were mostly guttural, and that the organs of the mouth would at first be very little employed." [Orig. and Progr of Lang. v. 1. b iii ch 4] To which I may add, that notwithstanding, in the ordinary use of speech, the tongue takes an auxiliary part among mankind, yet the numerous and well-authenticated examples on record, and to which we will have occasion to advert more minutely hereafter, of persons who have a retained a full and perfect command of speech after the tongue has been destroyed or extirpated, proves incontrovertibly that the glottis alone is capable of supplying, in this respect, the place of the tongue, upon particular occasions, and when perhaps particular pains are taken to call forth the full extent of its latent powers.

This explanation, which some hundreds of persons in this metropolis may remember to have been advanced by the author, in a public lecture on the subject delivered in the year 1811, has since been embraced in France, though without adopting the hint that the full perfection of the art may depend upon some slight addition to the muscular organism of the glottis, in those who are thus highly endowed with it. And hence M. Magendie asserts, that ventriloquism consists in nothing more than a delicate attention to the different modifications of sound, or speech, thrown at different distances, and through different modes of conveyance, and an exact imitation of them in a larynx of common formation and powers.

"Les fondemens sure lesquels repose cet art sont facils à saisir. Nous avons instinctivement reconnu, par l'experience, que les sons s'alterent par plusieurs causes; par exemple, que s'affaiblissent, deviennent moins distincts, et changent de timbre à mesure qu'ils s'eloignent de nous. Un homme est descendu au fond d'un puits, il veut parler aux personnes qui sont à l'ouverture: sa voix n'arrivera à leur oreille qu'avec des modifications dependantes de la distance, de la forme du canal qu'elle a parcouru. So donc une personne remarque bien ces modifications, et s'exerce à les reproduire, il produira les illusions d'acoustique, dont on ne pourra pas plus se defendre, qu'on peut ne pas voir les objects plus gros lorsqu'on les regarde à travers un verre grossisant: l'erreur sera complète s'il emploie d'ailleurs les prestiges convenables pour de tourner l'attention.

Plus l'artiste aura de talens, plus les illusions seront nombreuses: mais il faut se garder de croire qu'un ventriloque produise les sons vacaux, et articule autrement qu'une autre personne. Sa voix se forme à la manière ordinaire. Sous un certain rapport, on peut dire que cet art est à l'oreille ce que la peintre est pour les yeux." [Précis Elementaire de Physiologie, Tom II p 235]

But this last view of an ordinary articulation and formation of the voice, is at variance with that perfect acquiescence of the muscles of the cheeks and lips which the more skilful ventriloquists evince, and which can only be accounted for by a formation of articulations, and not merely a modification of sounds, in the larynx....

In the Physiological Proem to the present Class, we had occasion to remark that the glottis alone, in some instances, either from a greater pliancy and volubility of the muscles proper to it, or from the possession of some superadded muscle or membrane, seems to have a power of forming distinct articulations without the assistance of the tongue; and I have endeavoured to account for that sigular talent which we denominate ventriloquism. But there is a more singular talent still that sometimes occurs in the history of the human voice, and which is probably resolvable into the same cause; for we have examples, suggested by indisputable authentication, or persons who, having lost the entire organ of the tongue, and a few of them of the uvula also, have still retained a power of speaking, and even of expressing themselves with a clear and distinct enunciation. Such examples, indeed, are not very common; but they seem to have occurred in all ages, and especially when it was the custom among Turks, Goths, and other half-civilized nations, to cut out the tongues of the unhappy wretches whom the chance of war had thrown into their hands as prisoners... 

To explain this unexpected power, we should not only turn our attention to what is actually and in our own day accomplished by ventriloquists, but should recollect that the tongue is only a single organ employed in the articulation of sounds, and that the fauces, nostrils, lips, and teeth, bear, at least, an equal part, while the glottis, which forms all the vocal or vowel sounds, is the chief organ of the whole.

It is singular that so delicately sensitive an organ as the tongue should receive the severest injuries, and submit to very violent operations, with less serious mischief than almost any other organ of the same size in the body.