At the same time I satisfied myself of the existence of a pair of cartilages—the cuneiform cartilages described in the [Appendix]. I found these always in the female larynx, but only now and then in the male. As these cartilages, also found within the membranes of the vocal ligaments and reaching from their junction with the arytenoid cartilages to the middle of the ligaments, are only now and then fully formed in the male larynx, but undeniably work the shutting part of the glottis, it follows plainly that only a few male voices are capable of producing the head tones.
But observation with the microscope revealed in those larynxes in which the cuneiform cartilages were wanting, parts of a cartilaginous mass, or the rudiments of a cartilage, in the place indicated.
For anatomical investigations the male larynx is commonly used, its muscles being more powerful and its cartilages firmer than in the female larynx, and this explains why anatomists in Germany have been reluctant to admit the existence of the cuneiform cartilages. It was, therefore, a great satisfaction to me to find them described under the name of cuneiform cartilages in Wilson’s Human Anatomy, with the remark that they are sometimes wanting.[ 4 ]
The head register possesses a very great capacity of expansion, which, without the slightest straining, may be gradually extended, with some practice, a whole octave, and often even still farther upwards. When the transition is made from the highest tones of the falsetto register to the head register, there is experienced the same sense of relief in the organs of singing as in passing from the chest to the falsetto register. And this is very easy to be understood, because the ligaments by this repeated partial closure of the glottis are much less stretched than in the highest tones of the preceding lower register. The difference in sound between the highest tones of the falsetto and head registers is often slight, on which account these two registers, so different in their mechanism, are easily confounded. Only in entirely healthy vocal organs can the head tones be observed. A too great secretion of mucus, or any inflammation of the mucous membrane, embarrasses the formation of head and falsetto tones, while the vibrations of the fine edges of the vocal ligaments are thereby obstructed. The character of the vocal organ fully explains why in the case of sick or of worn-out voices it is always the high tones that are first lost. When I have observed, in the sick, irritation of the mucous membrane, I have often found the oval orifice which is formed in the production of the head tones entirely covered with mucus. In my own case, when by repeated effort this bubble of mucus broke, instead of the a2
, which I meant to be sounded, there came the a3, an octave higher, which in perfect health it was never possible for me to reach. I have observed the same phenomenon sometimes in my pupils.
When one sings the scale, note by note downwards, one can sing with the action of the higher register many of the tones of the lower, without any observable straining of the organ; indeed, there is a perceptible feeling of relief; only these tones are not so full as when sung in their natural register.
ABNORMAL MOVEMENTS OF THE GLOTTIS
Garcia states, in his observations, that sometimes when the rims of the vocal ligaments have come together, there remains between the arytenoid cartilages a triangular space, which does not close until the tone is produced. Czermak likewise describes this process in his pathological investigations, and also a similar one with the laryngoscope. While, namely, the arytenoid cartilages seem to be wholly closed, one sees just before the beginning of the tone the vocal ligaments standing apart in a square-shaped form, and only closing together with the tone. At first, before I had attained to much practice in observation, I often saw these processes in myself, and later often in others.
That these accidental forms of the glottis bear no relation to the generation of sounds, as Funke truly says, is made evident by an irregularity in the combined action of the muscles of the larynx, by which the coming together of the arytenoid cartilages takes place later than that of the ligaments, or that of the ligaments later than that of the arytenoid cartilages.