326 VOICE AND SPEECH. 



termined by the length of the cords and their tension. Other 

 things being equal, the size of the larynx would determine the 

 pitch. 



The larynx by itself produces vocal sound merely. In 

 speech the sounds produced in the larynx are much modified 

 by the lips, tongue, teeth, cheeks, etc. 



We have voice as soon as born, but we only gradually 

 acquire the power of speech. Mammals, birds, and some of 

 the lower vertebrates have voices, but they have not speech. 

 This distinguishes man from the animals below him, though 

 perhaps some of the higher apes have it in a slight degree. 

 Dogs can express their wants by barking, growling, snarling, 

 etc., but it is mostly by their tone, with their attitudes, and 

 a slight facial expression (as in snarling). 



By various positions of the tongue and organs of the 

 throat we make the different vowel sounds. In the conso- 

 nants we more or less shut off (for the time) the passage 

 of air, and so stop, or modify, the sound. This is hardly 

 the place to study and analyze the sounds of our spoken 

 language, yet it may be found profitable to watch the differ- 

 ent organs as each sound is produced; for when the structure 

 and relation of the different parts concerned in the pro- 

 duction of these sounds are better known, the definitions 

 and statements of the books will be much more fully under- 

 stood. 



Since no two throats are exactly alike, no two voices 

 sound just the same. The size and shape of the pharynx, 

 the shapes and positions of the teeth, lips, the condition of 

 the mucous membrane of the passages generally, all affect the 

 sound, and give it its " quality " by which we distinguish one 

 voice from another, even if they are in the same pitch and 

 have the same degree of loudness. 



If the mucous membrane covering the vocal cords is in- 



