1096 SPEECH. [BOOK in. 



quality, due to the dominance of a particular tone, originating 

 in the glottis and reinforced by the conformation of the vowel 

 chamber. This view at least, as expounded above, is the one 

 generally held ; but recent observations based on graphic records 

 have, it is right to say, thrown some doubt on the matter ; these 

 we cannot discuss here. There are moreover many subsidiary 

 questions connected with the formation of vowels into which we 

 cannot enter here. We will merely add that in uttering a true 

 diphthong, the conformation of the vowel chamber proper to the 

 initial vowel is changed rapidly but gradually and without any 

 obvious break into that proper to the final vowel. 



681. Consonants. These as we have already said in some 

 cases so far resemble vowels in that they are modifications of 

 the voice, that is to say of laryngeal sounds, caused by the dis- 

 position of the parts of the vowel chamber, the disposition how- 

 ever being in all such cases different from that giving rise to a 

 vowel, and moreover the very assumption of the disposition tak- 

 ing part in the generation of the whole sound. Such consonants 

 however are relatively few, the great majority of consonants are 

 caused by changes which set up vibrations in some part or other 

 of the vowel chamber or in the larynx itself ; they are noises 

 which may or may not be accompanied by voice, the vibrations 

 producing a different consonant according as they are or are not 

 accompanied by voice. Such vibrations may be set up in several 

 ways. In the case of many consonants vibrations are set up by 

 the passage being closed and then suddenly opened at a particu- 

 lar part ; such consonants are spoken of as explosives. In the 

 case of these consonants the noise which is their essential part 

 cannot be prolonged, it is momentary in duration, though when 

 it is accompanied by voice the latter may continue for some 

 time. In the case of other consonants the noise is caused by the 

 rush of air through a narrow space and the consonants may be 

 described as ' frictional ' ; or the noise may be produced by the 

 vibratory movements of particular parts. Both these kinds of 

 consonants can naturally be prolonged for an indefinite time, 

 and have been called continuous consonants. 



On the other hand the characters of a consonant are also 

 dependent on the particular part of the passage at which they 

 are generated; and this also may be used as a means of classifi- 

 cation. Some consonants are produced at the lips by the move- 

 ment or position of the lips in reference to each other or to 

 the teeth; these are called labial and labio-dental consonants. 

 Others again are produced by the movement or position of the 

 tongue in reference to the teeth or to the teeth and hard palate ; 

 these are called dental. Yet others are produced by the move- 

 ment of the back of the tongue in relation to the soft palate and 

 pharynx or fauces ; these are called guttural consonants, the 

 name being also applied to certain consonants which are essen- 



