760 



VOICE AND SPEECH 



[CH. LV. 



complicated by smaller ones on their surface, at twice, thrice, etc., 

 the rate of the primary vibration. The richer a voice, the richer the 

 sound of a musical instrument, the more numerous are these over- 

 tones or harmonics. 



The range of the voice is seldom, except in celebrated singers, 

 more than two-and-a-half octaves, and for different voices this is in 

 different parts of the musical scale. 



Although the voice is usually produced by the expiratory blast, 

 by practice one can employ the inspiratory blast ; this constitutes 



FIG. 560. Konig's apparatus for obtaining flame pictures of musical notes. 



the form of speech known as ventriloquism. The voice does not 

 appear to come out of the speaker's mouth ; and as we never readily 

 distinguish the direction in which the sounds reach our ear, the 

 ventriloquist, by directing the attention of the audience to various 

 parts of the room, is able to make them imagine the voice is pro- 

 ceeding from those parts. 



Speech. 



This is due to the modification produced in the fundamental 

 laryngeal notes, by the resonating cavities above the vocal cords. 

 By modifying the size and shape of the pharynx, mouth, and nose, 

 certain overtones or harmonics are picked out and exaggerated : this 

 gives us the vowel sounds ; the consonants are produced by inter- 

 ruptions, more or less complete, of the outflowing air in different 

 situations. The soft palate is raised at each word. When the 

 larynx is passive, and the resonating cavities alone come into play, 

 then we get whispering. 



