230 THE VOICE. 



articles, when the act of swallowing takes place. It also 

 assists in modifying the voice. 



7. The Vocal Cords. Within the larynx, and stretched 

 across it from the thyroid cartilage in front to the aryte- 

 noid cartilages behind, are placed the two sets of folds, 

 called the vocal cords. The upper of these, one on each 

 side, are the false cords, which are comparatively fixed and 

 inflexible. These are not at all essential to the formation 

 of vocal sounds, for they have been injured, in those lower 

 animals whose larynx resembles that of man, without ma- 

 terially affecting their characteristic cries. Below these, 

 one on each side, are the true vocal cords (Fig. 55, F), 

 which pursue a similar direction to the false cords, namely, 

 from before backward. But they are composed of a highly 

 elastic, though strong tissue, and are covered with a thin, 

 tightly-fitting layer of mucous membrane. Their edges 

 are smooth and sharply defined, and when they meet, as 

 they do in the formation of sounds, they exactly match 

 each other. 



8. Between the true and false vocal cords is a depression 

 on each side, which is termed the ventricle of the larynx 

 (Fig. 55, D). The integrity of these true cords, and their 

 free vibration, are essential to the formation of the tones 

 and the modulation of the natural voice. This is shown 

 by the fact that, if one or both of these cords are injured 

 or become diseased, voice and speech are compromised; 

 or when the mucous membrane covering them becomes 

 thickened, in consequence of a cold, the vocal sounds are 

 rendered husky and indistinct. When an opening is made 

 in the throat below the cords, as not infrequently happens 

 in consequence of an attempt to commit suicide, voice is 

 impossible except when the opening is closed by external 

 pressure. 



7 Wh-r( are the vocal corrl< ? The fnlsc rrtrds? The true cords? 

 8. Whcni i* the ventricl of the larynx? The essentials to the formation of the 

 tones and modulation of the voice ? 



