VOICE, SONO AND SPEECH. 



265 



the act of inspiration (Fig. 3), are wide open so as to allow the free 

 ingress of air, and even during ordinary expiration (Fig. 3) they 

 remain sufficiently wide open not to hamper the freedom of respira- 

 tion. When the voice is used, however, the lungs having obtained the 

 necessary supply of air, the edges of the vocal cords are brought to- 

 gether (Fig. 1), and, as the air is forced through them by the con- 

 traction of the lungs, they are set up in vibration, thus producing 

 the voice. 



Two vertical sections of the larynx are shown 

 in Figs. 4 and 5 (after Merkel), the former 

 showing the vocal cords (1, 2) in the lower 

 register, and the latter the vocal cords (1, 2) in 

 the high register. In both Figs., 5 and 6 rep- 

 resent the pockets or ventricles of the larynx, 

 and 3 and 4, the ventricular bands, sometimes 

 called the false vocal cords. Figs. 7 and 8 show 

 a section of a cartilage of the larynx. 



The voice, like other sounds, varies in pitch, loudness and timbre. 

 The pitch is due to the tension of the vocal cords, the process, how- 

 ever, being somewhat more complicated than in a violin in which 

 there are several strings. There being but one pair of vocal cords in 

 the larynx, the tones are produced, first, by tightening the vocal cords, 

 and, when the limit has been reached, so that a greater degree of ten- 

 sion would be injurious to the vocal cords and the muscles which con- 

 trol them, there is set up a different form of vibration known as the 

 change of register. This subject of the register is somewhat compli- 



FiG. 3. Vocal Cords Dur- 

 ing Expiration. 



Figs. 4 and 5. Vertical Sections of Larynx. 



cated, but it will be better understood if we suppose that the difference 

 between a low and a high register is due to the fact that in the latter 

 a shorter portion of the vocal cords is set into vibration. 



The bass, for instance, produces his lower tones by increasing the 

 tension of the vocal cords until B flat (International Pitch) is reached 

 when he changes his register, obtaining his remaining upper tones by 

 contracting the vocal cords in this register. The untrained singer, 

 however, not understanding this change of register, may attempt to 

 reach the upper tones by simply increasing the tension in the lower 



