938 OP THE VOICE AND SPEECH. 



prolonged ad libitum. The former have received the designation of explosive ; 

 and the latter of continuous. In pronouncing the explosive consonants, the pos- 

 terior nares are completely closed, so that the exit of air through the nose is 

 altogether prevented ; and the current may be checked in the mouth in three 

 ways, by the approximation of the lips by the approximation of the point of 

 the tongue to the front of the palate and by the approximation of the middle 

 of the tongue to the arch of the palate. In the first of these modes, we pro- 

 nounce the letters 5, and p ; in the second, d, and t; in the third, the hard g, 

 and k. The difference between 6, d, and g, on the one hand, and p, t, and &, 1 

 on the other, seems to depend on this that in the former group the approximating 

 surfaces are larger, and the breath is sent through them more strongly at the 

 moment of opening than in the latter. The continuous consonants may be 

 again subdivided, according to the degree of freedom with which the air is al- 

 lowed to make its exit, and the compression which it consequently experiences. 

 I. The first class includes those, in which no passage of air takes place through 

 the nose, and in which the parts of the mouth that produce the sound are nearly 

 approximated together, so that the compression is considerable. This is the 

 case with v, and /, which are produced by approximating the upper incisors to 

 the lower lip ; and which stand in nearly the same relation to each other, as 

 that which exists between d and t, or b and p. The sibilant sounds, z and s, 

 also stand in a similar relation to each other ; they are produced by the passage 

 of air between the point of the tongue and the front of the palate, the teeth being 

 at the same time nearly closed. The simple sound sh is formed by narrowing 

 the channel between the dorsum of the tongue and the palate ; the former being 

 elevated towards the latter, through a considerable part of its length. If, in 

 sounding s, we raise the point of the tongue a very little, so as to touch the 

 palate, the sound of t is evolved ; and in the same manner d is produced from 

 z. This class also includes tfie th ; which, being a perfectly simple sound, ought 

 to be expressed by a single letter, as in Greek, instead of by two, whose com- 

 bination does not really produce anything like it. For producing this sound, 

 the point of the tongue is applied to the back of the incisors, or to the front of 

 the palate, as in sounding t f but, whilst there is complete contact of the tip, 

 the air is allowed to pass out around it. n. In the second class of continuous 

 consonants, including the letters m, ?i, ?, and r } the nostrils are not closed; and 

 the air thus undergoes very little compression, even though the passage of air 

 through the oral cavity is almost or completely checked. In pronouncing m 

 and n, the breath passes through the nose alone : and the difference of the sound 

 of these two letters must be due to the variation in the form of the cavity of the 

 mouth, which acts by resonance. The letter m is a labial, like b ; and the only 

 difference between the two is, that in the former the nasal passage is open, whilst 

 the mouth remains closed; whilst in the latter, the nose is entirely closed, and the 

 sound is formed at the moment of opening the mouth. The same correspondence 

 exists between n and t, or n and g (the particular part of the tongue approximated 

 to the palate not being of much consequence in the pronunciation of n); and hence 

 it is that the transition from n to , or from n to g, is so easy, that the combina- 

 tions nt and ng are found abundantly in most languages. The sound of I is pro- 

 duced by bringing the tip of the tongue into contact with the palate, and allowing 

 the air to escape around it, at the same time that a vocal tone is generated in the 

 larynx ; it differs, therefore, from th in the position at whiclvthe obstruction is inter- 

 posed, as well as in the slight degree of compression of the air which it involves. 

 The sound of the letter r depends on an absolute vibration of the point of the tongue 



1 For the sake of proper comparison, this letter should be sounded not as kay, but as key. 



2 Hence it is easy to understand the substitution of t or d, for the English th, by 

 foreigners. 



