Speakers, singers and stammerers / by Frederick Helmore.

  • Helmore, Frederick.
Date:
1874
Catalogue details

Licence: Public Domain Mark

Credit: Speakers, singers and stammerers / by Frederick Helmore. Source: Wellcome Collection.

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    one another—each in every pair acting alternately as a check upon the other. The vocal cords may moreover be tightened by the ac- tion of the thyroid cartilage to which it must be remembered the other ends of the vocal cords are attached ; and so by the depression of the thyroid cartilage the cords are tight- ened. The pitch of a note depends upon the slackness or tightness of the cord. The tighter they are drawn the higher the pitch, the slacker so much the lower. Every one who has seen a stringed instrument tuned, of course, knows this. Immediately above the vocal cords are two small pouches or recesses called the ventricles of the larynx (g, figs. I, 3.) Above these again are situated the false vocal cords. So that the ventricles are between the false and real vocal cords. The epiglottis, already mentioned, is a small cartilaginous body attached principally to the upper margin of the thyroid cartilage. It can be opened or closed at will to meet vocal requirements or to close the entrance to the wind-pipe during the act of swallowing, (d, figs, i, 2.) The action of the vocal cords in the production of sound has by the researches of learned physiologists been declared to bear no resemblance to that of vibrating strings, and that it does not assimilate to the flute-pipes of an organ ; but that it is, in all essential particulars, the same with that of the reeds of the oboe and clarionet or the tongues of the accordion or concertina. (Carpenter's Manual of Physio- logy.) Some have thought that the ^olian harp was in some way acted upon, similarly to the vocal cords. During the last century a great controversy took place in France, principally between MM. Dodart and Ferrein. One argued that the tones of the voice were regulated entirely by the opening of the glottis : the other, M. Ferrein, that the vibra- tions of the lips or Hgaments of the glottis, acted upon by the air from the lungs, as the bow acts upon a vioHn-string,