OP ARTICULATE SOUNDS. 935 



except through the particular mode of discipline by which the congenitally deaf 

 may be trained to speak. Such persons are debarred from learning the use of 

 Voice in the ordinary manner ; for the necessary guidance cannot be afforded, 

 either through sensations of the present or conceptions of the past, and the 

 imagination is entirely destitute of power to suggest that which has been in no 

 shape experienced. But they may be taught to acquire an imperfect speech, 

 by causing them to imitate particular muscular movements, which they may be 

 made to see ; being guided in the imitation of those movements, in the first 

 place by watching their own performance of them in a looking-glass, and after- 

 wards by attending to the muscular sensations which accompany them. Many 

 instances, indeed, are on record, in which persons entirely deaf were enabled to 

 carry on a conversation in the regular way ; judging of what was said by the 

 movements of the lips and tongue, which they had learned to connect with 

 particular syllables ; and regulating their own voices in reply, by their volun- 

 tary power, guided in its exercise by their muscular sensations. 1 



[In the foregoing account of the Physiology of Voice, the Author has been chiefly guided 

 by the excellent paper by Mr. Willis in the "Transactions of the Cambridge Philosophical 

 Society," vol. iv. ; and by the elaborate investigations of Miiller and his coadjutors, as 

 detailed in the Fourth Book of his Physiology. Mr. Bishop's account of the Physiology 

 of Voice, in the Fourth Volume of the "Cyclopaedia of Anatomy and Physiology" may 

 also be advantageously consulted.] 



2 . Of Articulate Sounds. 



937. The larynx, as now described, is capable of producing those tones of 

 which Voice fundamentally consists, and the sequence of which becomes Music : 

 but Speech consists in the modification of the laryngeal tones, by other organs 

 intervening between the Glottis and the Os externum, so as to produce those 

 articulate sounds of which language is formed. It cannot be questioned that 

 Music has its language ; and that it is susceptible of expressing the emotional 

 states of the mind, among those at least who have been accustomed to associate 

 these with its varied modes, to even a higher degree than articulate speech. 

 But it is incapable of addressing the intellect, by conveying definite ideas of 

 objects, properties, actions, &c., in any other way than by a kind of imitation, 

 which may be compared to the signs used in hieroglyphic writing. These ideas 

 it is the peculiar province of articulate language to convey ; and we find that 

 the vocal organ is adapted to form a large number of simple sounds, which may 

 be readily combined into groups, forming words. The number of combinations 

 which can be thus produced is so inexhaustible, that every language has its 

 own peculiar series ] no difficulty being found in forming new ones to express 

 new ideas. There is considerable diversity in different languages, even with 

 regard to the use of the simplest of these combinations ; some of them are more 

 easy of formation than others, and these accordingly eater into the composition 

 of all languages ; whilst of the more difficult ones, some are employed in one 

 language, some in another no one language possessing them all. Without 

 entering into any detailed account of the mechanism required to produce each 

 of these simple sounds, a few general considerations will be offered in regard to 

 the classification of them ; and the peculiar defect of articulation, termed Stam- 

 mering, will be briefly treated of. 



938. Vocal sounds are divided into Vowels and Consonants; and the dis- 

 tinctive characters of these are usually considered to be, that the Vowels are 

 produced by the Voice alone, whilst the sound of the Consonant is formed by 

 some kind of interruption to the voice, so that they cannot be properly expressed 



1 See Dr. Johnstone "On Sensation," p. 128. 



