OF THE VOICE AND SPEECH. 107 



fatal, it does so by paralysing the muscles that dilate the glottis, 

 for the arytenoid muscle that closes the back part of it, being 

 supplied by the superior laryngeal, acts unopposed. 



" It is therefore evident that the larynx represents a reed with 

 two plates, the tones of which are acute in proportion as the 

 plates are short, and grave in proportion as they are long. But 

 although this analogy is just, we must not imagine that there is 

 a perfect identity. In fact, common reeds are composed of 

 rectangular plates fixed on one side and free on the three others, 

 while the vibrating plates of the larynx, which are also nearly 

 rectangular, are fixed on three sides and free on one only. 

 Besides, the tones of common reeds are made to ascend or 

 descend by van ing their length ; but the plates of the larynx 

 vary only in breadth. Lastly, the moveable plates of the reeds 

 of musical instruments cannot, like the ligaments of the glottis, 

 change every moment in thickness and elasticity." The changes 

 in both the length and breadth of the trachea and of the cavity 

 between the glottis and the lips, and in the state of the epiglottis 

 and the ventricles of the larynx, must affect the voice* 



(li) I am indebted to the tremendously powerful Conyers 

 Middleton for the knowledge of two cases of distinct articula- 

 tion with at least but little tongue. f In his exposure of the 

 difference between the pious deceptions of weak and wicked 

 Christians during the first centuries and the sublime miracles of 

 Christ and his apostles, he notices a pretty tale of an Arian 

 prince cutting out the tongues of some of the orthodox party and 

 these being as able to talk as before ; nay one (O hominum im- 

 pudentia ! ) who had been dumb from his birth, gained the faculty 

 of speech by losing his tongue. Granting the fact, and even 

 that the tongues were completely extirpated, he refers, for the 

 purpose of proving there was no miracle in the case, to two 



* F. Majcndie, Precis Elemcntaire dc Physiologic. T. i. p. Cifi sq. 



|- .In Enquiry itifo the miraculous Powers, ffs. Miscellaneous Works, vol. i. 



