To conclude this chapter, it only remains for me to mention a phenomenon, which, by its singularity, is worthy of the attention of physiologists; it is known by the name of ventriloquism, and those who possess it are called ventriloquists, because their voice, which is always weak and not very sonorous, seems to come from the stomach. There resides in the ci-devant Palais Royal, in the coffee-house of the grotto, a man who can maintain a dialogue with such accuracy, that we should be induced to believe two persons were actually engaged in conversation at a certain distance from each other, the accent and voice of whom seem to be entirely different. I have observed that he does not inspire when speaking from the belly, but that the air passes in smaller quantity from the mouth and nostrils than when in ordinary speech. Every time that he exerts this unusual peculiarity, he suffers distention in the epigastric region; sometimes he perceives the wind rolling even lower, and cannot long continue this exertion without fatigue.

At first I had conjectured that a great portion of the air expelled by expiration did not pass out by the mouth and nostrils, but was swallowed and carried into the stomach, reflected in some part of the digestive canal, and gave rise to a real echo; but having afterwards more attentively observed this curious phenomenon in M. Fitz-James, who represents it in its greatest perfection, I was enabled to convince myself that the name ventriloquism is by no means applicable, since the whole of its mechanism consists in a slow, gradual expiration, drawn in such a way that the artist either makes use of the influence exerted by volition over the muscles of the parietes of the thorax, or that he keeps the epiglottis down by the base of the tongue, the apex of which is not carried beyond the dental arches.

He always makes a strong inspiration just before this long expiration, and thus conveys a considerable mass of air into his lungs, the exit of which he afterwards manages with such address. Therefore repletion of the stomach greatly incommodes the talent of M. Fitz-james, by preventing the diaphragm from descending sufficiently to admit of a dilatation of the thorax, in proportion to the quantity of air that the lungs should receive. By accelerating or retarding the exit of air, he can imitate different voices, and induce his auditors to a belief that the interlocutors of a dialogue, which is kept up by himself alone, are placed at different distances; and this illusion is the more complete in proportion to the perfection of his peculiar talent. No man possesses to such a degree as M. Fitz-James the art of deceiving persons who are least liable to delusion: he can carry his execution to five or six different tones, pass rapidly from one to another, as he does when representing an animated dispute in the midst of a popular assembly. I have often heard him repeat the parts which he represents in Robertson's Phantasmagoria, where his comic and familiar exertions greatly add to the illusions represented.

Balthasar Anthelme Richerand, The Elements of Physiology: Containing An Explanation of the Functions of the Human Body, In Which the Modern Improvements in Chemistry, Galvanism, and Other Sciences Are Applied to Explain the Actions of the Animal Economy, trans. Robert Kerrison (London: John Murray, 1803)

The last paragraph in the 1815 edition reads:

He can set his organ to five or six different tones, pass rapidly from one to the other, as he does when he represents a very eager discussion, in a popular society of the people, imitate the sound of a bell, and carry on, singly, a conversation, in which one might think that several persons of different ages and sexes were taking parts. But what completes the illusion and especially distinguishes the art of the ventriloquist from that of the mimic, who can only counterfeit, consists in the power of so modulating his voice that one is deceived as to the distance of the speaker, in such sort, that one voice, comes from the street, another, from a neighbouring apartment, that, from one that had clambered up the roof of the house, &c. It is easy to discern the value of such a talent in the days of oracles.

Balthasar Anthelme Richerand, Elements of Physiology, New Edition, trans. G.J.M. de Lys (London: Thomas Underwood, John Callow/Edinburgh: Adam Black/Glasgow: John Smith and Son, 1815), p. 429.