CHAP, vii.] SPECIAL MUSCULAR MECHANISMS. 1089 



along its whole extent, though reduced to a mere linear slit; 

 but it is probable that in all cases the cords vibrate along a part 

 only and not along the whole of their length. In order to 

 throw into adequate vibrations the thin edges now presented, a 

 less powerful blast is required, and the vibrations are no longer 

 felt in the chest, though they are transmitted through the 

 pharyngeal passages to the head. 



As subsidiary conditions we may mention that in the chest 

 voice the superior aperture of the larynx is widely open, the 

 transverse diameter being perhaps especially long, while in the 

 head voice the aperture is constricted, at times remarkably so. 

 In the chest voice the epiglottis is usually depressed so as to 

 hide from sight, in the laryngoscopic view, the front part of the 

 cords, while in the head voice it is usually raised, but many 

 variations in the attitude of the epiglottis may be observed. In 

 the head voice the cartilaginous glottis seems always to be com- 

 pletely closed, whereas in the chest voice it is found in some 

 cases to be closed, in other cases to be more or less open. 



Making all allowance for discordance of opinion as to what 

 are the exact conditions of each kind of voice, and admitting 

 the imperfection of our knowledge as to both the purpose and 

 the mode of production of many of the differences observed, 

 we may at least draw the conclusion that in the case of each 

 kind of voice a certain general disposition of the mechanism is 

 made, that a certain ' setting ' of the machine takes place, by 

 which the quality of the voice is determined, and that the 

 machine thus set is played upon so as to produce a series of 

 notes differing in pitch but all retaining the same particular 

 quality. The setting of the machine in the chest voice is such 

 that the notes produced By it are lower notes reaching up to a 

 certain pitch only, the setting not being adapted for higher 

 notes, and conversely the setting of the head voice allows of 

 the production of high notes only, being incompatible with the 

 production of low notes. 



It may be urged that the setting for the chest voice is really 

 the natural disposition of the larynx and that of the head voice 

 a strange and artificial condition into which the larynx is 

 forced (and indeed the latter is in certain cases called a " fal- 

 setto " voice, which term however has a technical meaning not 

 always coincident with head voice) ; but a closer examination 

 of voices shews that there is in reality no one natural condi- 

 tion of the larynx, and that there are other dispositions or set- 

 tings of the larynx besides those of the chest voice and the 

 head voice, these being so to speak extreme cases. 



When a singer sings a series of notes in an ascending scale 

 it will be observed that beginning with the lowest notes the 

 voice during a certain range remains through all the notes of 

 the same quality, differing in pitch only, but that at or about a 



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