VOCAL SOUNDS. 133 



are produced under the conjoint influence of the larynx, fauces, and 

 mouth. In the majority of instances, the whole, or the greater num- 

 ber of the organs included in the mouth co-operate in producing 

 each articulate sound. The vowels alone are primarily formed be- 

 tween the vocal chords, and are continuous sounds, modified by the 

 shape of the aperture through which they pass out. The sound of 

 consonants is formed by some kind of interruption to the voice, so 

 that they cannot be properly expressed unless joined with a vowel. 

 It is the latter which commonly offer the greatest difficulty to the 

 stammerer, especially those which are called explosive. 



THE END. 



