ARTICULATE SOUNDS 491 



The cavity of the mouth assumes the same form for the articulation of each 

 of the mute vowels as for the corresponding vowel when vocalized; the only 

 difference in the two cases lies in the kind of sound emitted by the larynx. 

 It has been pointed out that the conditions necessary for changing one and the 

 same sound into the different vowels are differences in the size of two parts 

 the oral canal and the oral opening; and the same is the case with regard to the 

 mute vowels. By oral canal is meant here the space between the tongue and 

 palate : for the pronunciation of certain vowels both the opening of the mouth 

 and the space just mentioned are widened; for the pronunciation of other 

 vowels both are contracted; and for others one is wide, the other contracted. 

 Admitting five degrees of size, both of the opening of the mouth and of the 

 space between the tongue and palate, Kempelen thus states the dimensions of 

 these parts for the following vowel sounds: 



Vowel. Sound. Size of Oral Opening. Size of Oral Canal. 



a as in "far" 5 3 



a " " name " 4 2 



e " "theme" 3 i 



O " "go" 2 4 



oo " " cool" i 5 



Another important distinction in articulate sounds is that the utterance of 

 some is only of momentary duration, taking place during a sudden change in 

 the conformation of the mouth, and being incapable of prolongation by a con- 

 tinued expiration. To this class belong b, p, d, and the hard g. In the 

 utterance of other consonants the sounds may be continuous; they may be 

 prolonged, ad libitum, as long as a particular disposition of the mouth and a 

 constant expiration are maintained. Among these consonants are h, m, n, 

 f, s, r, 1. Corresponding differences in respect to the time that may be oc- 

 cupied in their utterance exist in the vowel sounds, and principally constitute 

 the differences between long and short syllables. Thus the a as in far and 

 fate, the o as in go and fort, may be indefinitely prolonged; but the same 

 vowels (or more properly different vowels expressed by the same letters), 

 as in can and fact, in dog and gotten, cannot be prolonged. 



All sounds of the first or explosive kind are insusceptible of combination 

 with vocal tone (intonation), and are absolutely mute; nearly all the conso- 

 nants of the second or continuous kind may be attended with intonation. 



The tongue, which is usually credited with the power of speech, plays 

 only a subordinate, although very important, part. This is well shown by cases 

 in which nearly the whole organ has been removed on account of disease. 

 Patients who recover from this operation talk imperfectly, and their voices are 

 considerably modified; but the loss of speech is confined to those letters in the 

 pronunciation of which the tongue is particularly concerned. 



Stammering depends on a want of harmony between the action of the 

 muscles (chiefly abdominal) which expel air through the larynx, and that of 



