238 THE HUMAN BODY. 



when these sounds are made without the aid of the lips, by 

 a peculiar disposition of the tongue, it is only a single sound. 

 It is the same in whistling through the teeth with the lips 

 drawn apart, or when the tongue being doubled, and the 

 ringers placed in the mouth, we produce an intensely acute 

 sound, but which cannot be modulated. 



In the apparatus for whistling, as in that of the voice, the 

 functional disposition, and its modifications in relation to the 

 sounds emitted, takes place by movements under the control 

 of the will, although they are, so to speak, instinctive. The 

 changes in the dimensions of the orifices and of the buccal 

 tube, in the tension of the walls of the mouth, the impulsion 

 of the air, &c., are all effected instantaneously, and in such a 

 manner as to produce all the notes. No instrument of music 

 equals the perfection of this apparatus. 



Voice. Voice is a sound produced in the throat by the 

 passage of the air through the glottis, as it is expelled from 

 the lungs. It is grave and strong in man, soft and higher in 

 woman; it varies according to age, and is developed simul- 

 taneously with the larynx, as has already been stated. It is 

 alike in both sexes in infancy, but is modified in youth; then 

 the voice is said to "change." In the young woman it de- 

 scends a note or two, and becomes stronger. In the young 

 man the change is much more strongly marked. At the 

 fourteenth or fifteenth year the voice loses its regularity, be- 

 comes harsh and unequal, the high notes cannot be sounded, 

 while the grave ones make their appearance, and the mascu- 

 line character of the voice is established. A year is gene- 

 rally sufficient for this change to be complete, and the voice 

 of the child gives place to that of the man. Exercise of the 

 voice in singing should be very moderate, if not entirely sus- 

 pended, while this change is going on. 



Speaking voice. Voice is divided into singing and speaking 

 voice. One differs from the other almost as much as noises do 

 from musical sounds. In speaking, the sounds are too short 

 to be easily appreciable, and are not separated by fixed and 

 regular intervals, like those of singing; they are linked together 

 generally by insensible transitions; they are not united by 

 the fixed relations of the gamut, and can only be noted with 



