I can increase the size of this ball above, to a pear shape, as soon as I think of singing higher; and, indeed, I heighten the form before I go on from the tone just sung, making it, so to speak, higher in that way, and thus keep the form, that is, the "propagation form," ready for the next higher tone, which I can now reach easily, as long as no interruption in the stream of breath against the mucous membrane can take place. For this reason the breath must never be held back, but must always be emitted in a more and more powerful stream. The higher the tone, the more numerous are the vibrations, the more rapidly the whirling currents circulate, and the more unchangeable must the form be.

Catarrh often dries up the mucous membrane; then the tones are inclined to break off. At such times one must sing with peculiar circumspection, and with an especially powerful stream of breath behind the tone: it is better to take breath frequently. In a descending scale or figure I must, on the contrary, preserve very carefully the form taken for the highest tone. I must not go higher, nor yet, under any circumstances, lower, but must imagine that I remain at the same pitch, and must suggest to myself that I am striking the same tone again. The form may gradually be a little modified at the upper end: that is, the soft palate is lowered very carefully behind the nose: keeping almost always to the form employed for the highest tone, sing the figure to its end, toward the nose, with the help of the vowel oo. (This auxiliary vowel oo means nothing more than that the larynx is slowly lowered in position.)

When this happens, the resonance of the head cavities is diminished, that of the palate increased; for the soft palate sinks, and the pillars of the fauces are raised more and more. Yet the head tone must not be entirely free from palatal resonance. Both remain to the last breath united, mutually supporting each other in ascending and descending passages, and alternately but inaudibly increasing and diminishing.

These things go to make up the form:—

The raising and lowering of the soft palate, and the corresponding lowering and raising of the pillars of the fauces.

The proper position of the tongue: the tip rests on the lower front teeth—mine even as low as the roots of the teeth.

The back of the tongue must stand high and free from the throat, ready for any movement. A furrow must be formed in the tongue, which is least prominent in the lowest tones, and in direct head tones may even completely disappear. As soon as the tone demands the palatal resonance, the furrow must be made prominent and kept so. In my case it can always be seen. This is one of the most important matters, upon which too much emphasis can hardly be laid. As soon as the furrow in the tongue shows itself, the tone must sound right; for then the mass of the tongue is kept away from the throat, and, since its sides are raised, it is kept out of the way of the tone.

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