Mr. Bishop on the Physiology of the Human Voice. 343 



the moment of transition, I found that the larynx suddenly 

 fell, and then continued to re-ascend as the tones became 

 more acute. On observing the motions of the larynx m a 

 mezzo-soprano voice, I found a double falsetto, consisting of 

 several tones of each register, with the power of yielding either 

 the primary or the falsetto character. In this case the larynx 

 fell twice, but in a much smaller degree. An instance of this 

 kmd of voice occurs in Miss Lanza. At the moment the la- 

 rynx falls, during the continued ascent of the tones, the co- 

 lumn ot air and the tube become divided into portions separated 

 by nodes, yielding harmonics of the fundamental notes, and 

 the modulations of the voice are regulated, as before, by the 

 divided length and relative tension of the tube. A much smaller 

 quantity of air is sufficient to produce these tones; conse- 

 quently, public singers who chiefly employ the falsetto, suffer 

 much less fatigue than those who use the primary notes. 



In conducting these observations, care must be taken that 

 the voice do not ascend or descend the scale too rapidly, other- 

 wise the effect may escape detection. In further confirmation 

 of these views it may be remarked, that when the glottis is in- 

 jured and silenced by disease, the voice is entirely annihilated, 

 which could not be the case if there were any means of pro- 

 ducing sound by the superior ligaments of the larynx. There 

 is, however, no doubt that the human voice derives a portion 

 of Its peculiar quality from the reverberations of sound in the 

 cavities of the chest and head, modified by every change in 

 these cavities as well as in the vocal tube. (The great effect 

 produced by the nasal cavities on the voice is well known.) 



Much pains have been taken by physiologists to find an 

 analogy between the organs of voice and artificial musical in- 

 struments. Amongst those which have been selected for this 

 purpose are the drum, the duck-whistle, the reed, and various 

 other wind and stringed instruments. These attempts serve 

 to illustrate the complicated structure and functions of the vo- 

 • cal organs ; but it appears to me more simple, and at the same 

 time nearer the truth, to consider them in the following point 

 of view : 



They consist of elastic membranes inclosed in a tube. The 

 glottis is a most complex and beautifully constructed mem- 

 branous vibrating apparatus, exquisitely adapted for producing 

 all the tones of the voice. The vocal tube, or pipe, is adjusted 

 on the most refined acoustic principles, to yield with the glottis 

 isochronous vibrations. 



The perfect adaptation of these organs, in a manner inimi- 

 table by mechanical art, to produce the most melodious sounds, 



