242 



THE HUMAN BODY. 



Singing. We generally recognize two series of sounds in 

 the voice in singing, one comprising the grave and semi-acute 

 notes, and the other the high notes; this is called the register 

 of the voice, one is the chest register or voice, and the other 

 the head register or voice, or falsetto. Some writers admit a 

 third series or mixed voice, which resembles a diminutive 

 chest-voice, in quality and in the disposition of the glottis 

 when it is produced. 



We have indicated already the principal physiological 

 theories on the formation of the voice in general: there is 

 no less diversity in opinion in regard to the falsetto. Accord- 

 ing to Miiller, it results from the vibrations of the edge only 

 of the vocal cords; other authors incline to the notion that 

 the glottis no longer vibrates like a reed, but like the mouth- 

 piece of a flute. M. Segond makes the falsetto voice to come 

 from the superior glottis exclusively, that is to say, from the 

 vibration of the superior thyro-arytenoid ligaments. This 

 opinion has been refuted by the experiments of M. Longet. 

 And lastly, Weber and Longet attribute the origin of the 

 falsetto notes to the harmonics of the vocal cords. 



The laryngoscope enables us to study the glottis during 

 the emission of the chest-notes, and even of the falsetto 

 notes, but observers are not agreed upon the phenomena 

 which they have observed. 



According to Fournie, the chest, the falsetto, and the mixed 



Fig. 45. The glottis and vocal cords. 



A, E. Glottis in the chest-voice. 

 C. Glottis in thefalse-tto voice. 



voice, are all produced by the vibration of the mucous fold 

 which covers the free border of the vocal corcb. 



