In using the laryngoscope while the breath is quietly drawn, I saw, as Garcia did, the whole larynx wide open, so that one could easily introduce a finger into it, and the rings of the trachea were plainly visible.
a. Arytenoid cartilages. b. Epiglottis. c. Trachea.[2] d. Vocal chords.
When those who had become accustomed to the introduction of the instrument sang, at my request, _a_, as pronounced in the English word _man_, in a deep tone, the epiglottis rose, the tongue formed a cavity from within forwards, and thus rendered it easy to see into the larynx. So soon as the _a_, as in _father_, was sung, the cover quickly fell, the tongue rose, and prevented all observation of the organ of singing. The other vowels are still less favorable to observation, because they do not admit of any such wide opening of the mouth. Strong tones also are unfavorable to observation, as Garcia also remarked; and this is very natural, because strong and sonorous tones require greater exertions of the singing organ, and, above all things, the right position of those parts of the larynx and mouth which serve as a resonance apparatus in the formation of sound. In order to be able to see perfectly the whole glottis, all this resonance apparatus must be drawn back as far as possible, and the rim of the larynx must be tolerably flat. Thus only faint and weak sounds are favorable to observation.
When the vowel _a_, as in _man_, was sung, I could, after long-continued practice, plainly see how the arytenoid cartilages quickly rose with their summits in their mucous membranous case and approached to mutual contact. In like manner, the _chordæ vocales_, or inferior vocal chords, approached each other so closely that scarcely any space between them was observable. The superior or false vocal ligaments formed the ellipse described by Garcia in the upper part of the glottis.
[Representation in the mirror of the vocal organ in giving out sound.]
a. Superior or false vocal ligaments, or chords. b. Epiglottis. c. Inferior or true vocal ligaments. d. Arytenoid cartilages. e. Capitula Santorini.
When, in using the laryngoscope upon myself, I slowly sang the ascending scale, this movement of the vocal chords and arytenoid cartilages was repeated at every tone. They separated and appeared to retreat, in order to close again anew, and to rise somewhat more than before. This movement of the arytenoid cartilages may best be compared to that of a pair of scissors. With every higher tone the vocal ligaments seemed more stretched and the glottis somewhat shorter.--[The glottis is a term applied to the space occupied by the vocal chords (the lips of the glottis): when separated, we say the glottis is open, when they touch, that it is closed.]--At the same time, when I sang the scale upward, beginning with the lowest tones, the vocal ligaments seemed to be moved in their whole length and breadth by large, loose vibrations, which extended even to all the rest of the interior of the larynx.