ACTION OF THE ^ACCESSORY VOCAL OEGANS. 507 



quality. In the same way we explain the fact that the flute, 

 clarinet, or the sound from a Cremona violin, may be heard 

 soaring above the chords of a full orchestra. 



Action of the Accessory Vocal Organs. A correct use 

 of the accessory organs of the voice is of the greatest im- 

 portance in singing ; but the manner in which these parts 

 perform their function is exceedingly simple, and does not 

 require a very extended description. The human vocal 

 organs, indeed, consist of a vibrating instrument, the larynx, 

 and certain tubes and cavities by which the sound is reen- 

 forced and modified. 



The trachea serves not only to conduct air to the larynx, 

 but to reenforce the sound to a certain extent by the vibra- 

 tions of the column of air in its interior. When a powerful 

 vocal effort is made, it is easy to feel, with the finger upon 

 the trachea, that the air contained in it is thrown into vibra- 

 tion. The structure of this tube is such that it may be 

 elongated and shortened at will. In the production of low 

 tones, the trachea is shortened and its calibre is increased, 

 the reverse obtaining in the higher notes of the scale. 



Coming to the larynx itself, we find that the capacity of 

 its cavity is capable of certain variations. In fact, both the 

 vertical and the bilateral diameters are diminished in the 

 high notes and increased in low tones. The vertical diame- 

 ter may be modified slightly by ascent and descent of the true 

 vocal chords, and the lateral diameter may be reduced by 

 the inferior constrictors of the pharynx, acting upon the sides 

 of the thyroid cartilage. 



The epiglottis, the superior vocal chords, and the ventri- 

 cles are by no means indispensable to the production of vo- 

 cal sounds. In the formation of high tones, the epiglottis is 

 somewhat depressed, and the superior chords are brought 

 nearer together ; but this only affects the character of the 

 resonant cavity above the glottis. In low tones the su- 

 perior chords are separated. It was before the use of the 



