854 OF THE VOICE AND SPEECH. 



of the whole vocal organ, which takes place when we are sounding deep 

 notes, and its rise during the elevation of the tones, have been supposed to 

 answer the purpose of making this adjustment in the length of the trachea; 

 but this requires the supposition that the real length of the trachea is short- 

 ened whilst it appears extended for which there seems no foundation. It 

 is considered by Mr. Wheatstone that the column of air in the trachea may 

 divide itself into " harmonic lengths," and may produce a reciprocation of 

 the tone given by the vocal ligaments ( 642); and in this manner he con- 

 siders that the falsetto notes are to be explained. It may be added that the 

 partial closing of the epiglottis seems to assist in the production of deep 

 notes, just as the partial covering of the top of a short pipe fixed to a reed will 

 lower its tone ; and that something of this kind takes place during natural 

 vocalization, would appear from the retraction and depression of the tongue, 

 which accompany the lowering of the front of the head when the very lowest 

 notes are being sounded. The experiments of Savart have shown, that a 

 cavity which only responds to a shrill note, when its walls are firm and dry, 

 may be made to afford a great variety of lower tones, when its walls are 

 moistened and relaxed in various degrees. This observation may probably 

 be applied also to the trachea. 



700. The falsetto is a peculiar modification of the voice, differing from 

 the " chest-voice," not merely in the higher pitch of its notes, but also in 

 their quality; its tones being less reedy, and more like the " harmonic 

 notes" of stringed and wind instruments. In some individuals, the chest- 

 voice passes by imperceptible gradations into the falsetto, whilst in others 

 the transition is abrupt ; and some persons can sound the same notes in the 

 two different registers, these notes forming the upper part of the scale of the 

 chest-voice, and the lower part of the falsetto. 1 With regard to the theory 

 of the production of the falsetto-voice, there has been considerable differ- 

 ence of opinion amongst Physiologists ; and it cannot be regarded as fully 

 determined. By Magendie and Mayo it was maintained that these tones 

 are produced by the vibration of the vocal cords along only part of their 

 length, the rima glottidis being par.tly closed ; and this explanation is con- 

 sistent with the fact, that a far smaller quantity of air is required for sus- 

 taining a falsetto note, than for a note of the ordinary register, even though 

 they should be of the same pitch. By Mu'ller and Garcia,' 2 again, it is 

 asserted that in the production of the falsetto notes, merely the thin border 

 of the glottis vibrates, since the fibres of the lateral crico-arytenoid muscle 

 remains inactive, whilst the lips of the glottis, stretched by the horizontal 

 bundle of the thyro-arytenoid, come in contact by their edge alone, and 

 offer little resistance to the air. In the chest-voice, on the contrary, the 

 contraction of the lateral crico-aryteuoids gives a rotatory movement to the 

 cartilages, and increases the depth of the surface of contact of the two liga- 

 ments, and it is to this circumstance that the peculiar amplitude of the notes 

 of the chest-register is attributable. Mancll has demonstrated that both 

 these doctrines are correct; and that iu the production of falsetto notes, the 



1 Tims a gentleman of the Author's acquaintance has a bnss voice of a harsh, reedy 

 diameter, ranging from the D below the bass clef to the D above it (two octaves) ; 

 whilst, his falsetto", which is remarkable for its clearness and smoothness, ranges from 

 the A on the highest line of the bass clef to the E in the highest space of the treble 

 clef. Hence there are five notes common to the two registers, and the entire voice 

 ranges through more than three octaves ; but from want of a gradual passage from 

 one to the other, this eentleman can only sing bass parts with, his chest-voice, or alto 

 parts witli his falsetto, the tenor scale extending above the range of one, and below 

 that of the other. 



' l Proceedings of the Royal Society, vol. vii, p. 408 



