VOCAL PECULIARITIES 109 



the glottis (which is the opening between the vocal cords) 

 are two small sacs or ventricles. In the ape these are 

 larger and more flexible than in man. In the act of speak- 

 ing they are inflated by the air passing out of the lungs 

 into the long tube called the larynx. The function of 

 these ventricles is to control and modify the sound by 

 increasing or decreasing the pressure of the air that is 

 jetted through the tube. They serve at the same time 

 as a reservoir and as a gauge. 



In the louder sounds uttered by the chimpanzee these 

 ventricles greatly distend. This intensifies the voice or 

 increases its volume. It is partly due to these little sacs 

 that the ape is able to make such a loud and piercing 

 scream. But the pitch and volume of his voice cannot be 

 alone due to this cause, for the gorilla (in which these ven- 

 tricles are much smaller) can make a vastly louder sound. 

 We may be mistaken, however, about the sound commonly 

 ascribed to him. 



Although the sounds made by the chimpanzee can be 

 imitated by the human voice, they cannot be expressed or 

 represented by any system of phonetic symbols in use 

 among men. Alphabets have been deduced from picto- 

 graphs, and the conventional symbol that is used to repre- 

 sent a given sound has no reference to the organs of speech 

 that produced it. The few rigid lines that have survived 

 and that now form the alphabets are within themselves 

 meaningless, but they have been so long used to represent 

 the elementary sounds of speech that it would be difficult 

 to supplant them with others. 



As no literal formula can be made to represent the 



