344 Mr Willis on the 



NOTES. 



Note A. — Page 326. 



M. Savaet, whose labours in every branch of Acoustics have contri- 

 buted so greatly to the advancement of that science, has written an ingenious 

 Memoir, (Annales de Chimie, t. 30), in which he has endeavoured to shew- 

 that the sounds of the Larynx are produced, not by the vibration of the 

 vocal ligaments, but in a manner analogous to those of the little instru- 

 ment called a duck whistle, of which he has given a theory with experiments ; 

 this machine consists of a small circular box, in the centers of the flat sides 

 of which are two holes exactly opposite to each other. When a current of 

 air passes through these holes a sound is produced, and his whole explana- 

 tion rests upon the analogy between the section of the Larynx (Fig. 1.) 

 and of this instrument, of which the glottis and pseudo-glottis are sup- 

 posed to represent the two holes, and the ventricles the cavity. But his 

 mode of obtaining the form of the laryngeal cavity is to take a cast of 

 it in plaster, by which the ventricles are of course distended, and made 

 to assume a magnitude and consequence which they never can possess during 

 life, but which are essential to his theory. Neither does it appear to me 

 that he has been successful in applying this explanation to the muscular 

 structure of the Larynx. This instrument had been before made use of 

 with great success by Kempelen for the explanation and imitation of the 

 whistling and hissing sounds of the human voice, (Vide Mech. de la Parole). 



