THE VOICE AND SPEECH. 59 



are produced by the ordinary vibrations of the vocal cords. The mode of 

 production of the falsetto notes is still obscure. 



By Miiller the falsetto notes were thought to be due to vibrations of 

 only the inner borders of the vocal cords. In the opinion of Petrequin 

 and Diday, they do not result from vibrations of the vocal cords .at all, 

 but from vibrations of the air passing through the aperture of the glottis, 

 which they believe assumes, at such times, the contour of the embouchure 

 of a flute. Others (considering some degree of similarity which exists 

 between the falsetto notes and the peculiar tones called harmonic, which 

 are produced when, by touching or stopping a harp-string at a particular 

 point, only a portion of its length is allowed to vibrate) have supposed 

 that, in the falsetto notes, portions of the vocal ligaments are thus iso- 

 lated, and made to vibrate while the rest are held still. The question 

 cannot yet be settled; but any one in the habit of singing may assure 

 himself, both by the difficulty of passing smoothly from one set of notes 

 to the other, and by tbe necessity of exercising himself in both registers, 

 lest he should become very deficient in one, that there must be some 

 great difference in the modes in which their respective notes are produced. 



The strength of the voice depends partly on the degree to which the 

 vocal cords can be made to vibrate; and partly on the fitness for reso- 

 nance of the membranes and cartilages of the larynx, of the parietes of the 

 thorax, lungs, and cavities of the mouth, nostrils, and communicating 

 sinuses. It is diminished by anything which interferes with such 

 capability of vibration. The intensity or loudness of a given note with 

 maintenance of the same "pitch," cannot be rendered greater by merely 

 increasing the force of the current of air through the glottis; for increase 

 of the force of the current of air, cceteris paribus, raises the pitch both of 

 the natural and the falsetto notes. Yet, since a singer possesses the 

 power of increasing the loudness of a note from the faintest "piano" to 

 "fortissimo" without its pitch being altered, there must be some means 

 of compensating the tendency of the vocal cords to emit a higher note 

 when the force of the current of air is increased. This means evidently 

 consists in modifying the tension of the vocal cords. When a note is 

 rendered louder and more intense, the vocal cords must be relaxed by 

 remission of the muscular action, in proportion as the force of the current 

 of the breath through the glottis is increased. When a note is rendered 

 fainter, the reverse of this must occur. 



The arches of the palate and the uvula become contracted during the 

 formation of the higher notes; but their contraction is the same for a 

 note of given height, whether it be falsetto or not; and in either case the 

 arches of the palate may be touched with the finger, without the note 

 being altered. Their action, therefore, in the production of the higher 

 notes seems to be merely the result of involuntary associate nervous 

 action, excited by the voluntarily increased exertion of the muscles of the 



