1486 



VOICE. 



exercised at this time of life, and in support 

 of his views he cited the cases of Donzelli 

 and Donizetti, of whom the latter lost his 

 voice by singing, whilst the former retained it 

 by abstaining from singing at that period. 

 There are, however, man}' examples of per- 

 sons possessing fine voices, who never paid 

 the least attention to this rule. 



The oral, nasal, and pharyngeal cavities 

 exercise an important influence on the quality 

 of sounds after their production by the larynx. 

 Further effects are ascribed by Bennati to 

 the arches of the palate, the uvula, and velum, 

 all of which appear to contract with the acute, 

 and relax with the grave tones, and are in 

 constant motion during the modulation of the 

 voice. The contraction of these parts during 

 the production of acute sounds has also been 

 observed by Fabricius ab Aquapendente, 

 Meyer, Gerdy, and Dzoncli. Bennati con- 

 ceived, as has been already mentioned, that 

 the falsetto notes, which he calls notes " sur- 

 laryngiennes," are produced exclusively in the 

 superior part of the vocal tube ; but it has 

 been shown that this hypothesis is contrary to 

 acoustic principles, and that the same motions 

 of the palate are also equally observable during 

 the production of acute tones of the ordinary 

 register. Miiller also states that the arches of 

 the palate may be touched by the finger with- 

 out altering the pitch, which could not be the 

 case on the hypothesis of Bennati. It is to 

 be remarked that neither Miiller nor Bennati 

 mentions the opening of the crico-thyroid chink 

 on sounding the first note in the falsetto re- 

 gister ; neither do they mention the simul- 

 taneous falling of the larynx, and they deny 

 the existence of a third register. According 

 to the hypothesis of Lehfeldt and Miiller, any 

 increased intensity of vocal sound ought to 

 raise the pitch of the voice ; but if this were 

 the case, the performance of prolonged vocal 

 sounds on the same note, but of variable in- 

 tensity, would be rendered impossible without 

 a simultaneous adjustment between the tension 

 of the vocal ligaments and the current of air ; 

 whereas, by examining the state of the crico- 

 thyroid chink during the utterance of these 

 sounds, it is found that no such adjustment 

 takes place. The exquisite quality of the 

 sounds of the larynx, when modified by the 

 oral and nasal cavities, renders the human 

 voice far superior to any artificial musical in- 

 strument ; since its tones glide through all 

 the en-harmonic intervals between successive 

 notes, an effect which no such instrument can 

 perfectly imitate. Dodart estimates the num- 

 ber of tones which can be produced by the 

 voice and appreciated by the ear in the com- 

 pass of an octave, at three hundred : a striking 

 proof of the complete control exercised by 

 the laryngeal nerves over the vocal apparatus. 



The action of the vocal organs in producing 

 speech is a distinct branch of the physiology 

 of voice, which the author has elsewhere in- 

 vestigated.* It is well known that, the vowel 

 sounds have been imitated by Kratzenstein, 



* Vide " On Articulate Sounds, and on the Causes 

 and Cure of Impediments of Speech. London. 1851." 



De Kempelen, and Willis, by means of me- 

 chanism, and that the principles on which 

 they depend have been successfully analysed 

 by the latter : but this is a subject which 

 would require a very lengthened examination 

 to render it the justice which its importance 

 demands. 



Having now completed the investigation of 

 the physiological character of the human 

 organs of voice, and having for the sake of 

 simplicity considered them in three distinct 

 lights, namely, as membranous ligaments obey- 

 ing the laws of musical strings, as a reeded 

 instrument, and as a membranous pipe with 

 a column of air vibrating within it, the results 

 of the various experiments which have been 

 noticed would certainly seem to warrant the 

 conclusion that each of these views is cor- 

 rect ; for it cannot be denied that these ex- 

 periments clearly show the vocal apparatus to 

 be influenced by the air expelled from the 

 chest in precisely the same way as if it were 

 a stretched cord, a reed, or a vibrating tube. 

 Why then should we hesitate to adopt the 

 obvious conclusion that the vocal organs do in 

 fact combine the properties of these various 

 instruments, and are themselves the perfect 

 types of which these instruments are only im- 

 perfect imitations ? The error of those who 

 have preceded the author in this inquiry 

 seems to consist in viewing the organs of 

 voice, not as a complex, but as a simple ap- 

 paratus; with some the favourite hypothesis 

 has accordingly been that of musical strings, 

 with others that of a reed, while experiments 

 are equally in favour of both. 



It cannot be expected that in this brief 

 treatise, a subject, wherein, notwithstanding 

 the attention hitherto bestowed on it for many 

 years by men of the highest philosophical 

 talent, so little comparatively has been effected, 

 should be at once exhausted, and all its diffi- 

 culties removed ; but the inductive method, 

 the only satisfactory mode of reasoning on 

 such subjects, has been most scrupulously 

 pursued; and whatever explanations have been 

 offered of the phenomena of the voice are at 

 least founded on facts which are incontro- 

 vertibly established. 



COMPARATIVE ANATOMY AND PHYSIOLOGY 

 OF THE ORGANS OF VOICE. Having given 

 an outline of the structure and functions of 

 the vocal organs in man, and stated our 

 views of the principles on which the produc- 

 tion of voice depends, we shall now proceed to 

 the investigation of the physiology of voice in 

 the lower animals. 



Mammalia. In the various orders of mam- 

 malia the organs of voice present different 

 grades of development and complexity of 

 structure, producing in each case some pecu- 

 liarity of timbre, or quality of tone, by which 

 we are enabled to distinguish them from one 

 another. Some species are mute, such as the 

 giraffe, armadillo, and others, whilst some 

 possess voices of greater or less intensity. 



The organs of voice in the lower mammalia, 

 as well as in man, are composed of lungs, which, 

 considered in an acoustic point of view, act 



