Try to sing a scale upward on _ah_, placing the tongue and muscles of speech at the same time on _[=a]_, and you will be surprised at the agreeable effect. Even the thought of it alone is often enough, because the tongue involuntarily takes the position of its own accord.
I remember very well how Mme. Désirée Artot-Padilla, who had a low mezzo-soprano voice, used to toss off great coloratura pieces, beginning on the vowel-sound _ah_, and then going up and down on _a_, _ee_, _aüoah_. At the time I could not understand why she did it; now I know perfectly,--because it was easier for her. The breath is impelled against the cavities of the head, the head tones are set into action.
Behind the _a_ position there must be as much room provided as is needed for all the vowels, with such modifications as each one requires for itself. The matter of chief importance is the position of the tongue _in_ the throat, that it shall not be in the way of the larynx, which must be able to move up and down, even though very slightly, without hindrance.
All vowels must be able to flow into each other; the singer must be able to pass from one to another without perceptible alteration, and back again.
How easy it is for the Italians, who have by nature, through the characteristics of their native language, all these things which others must gain by long years of practice! A single syllable often unites three vowels; for instance, "tuoi" (tuoy[=e]), "miei" (myeay[=e]), "muoja," etc.
The Italians mingle all their vowels. They rub them into and color them with each other. This includes a great portion of the art of song, which in every language, with due regard to its peculiar characteristics, must be learned by practice.
To give only a single example of the difficulty of the German words, with the everlasting consonant endings to the syllables, take the recitative at the entrance of Norma:--
"Wer lässt hier Aufruhrstimme_n_, Kriegsruf ertöne_n_, wollt Ihr die Götter zwinge_n_, Eurem Wahnwitz zu fröhne_n_? Wer wagt vermesse_n_, gleich der Propheti_n_ der Zukunft Nacht zu lichte_n_, wollt Ihr der Götter Pla_n_ vorschnell vernichte_n_? Nicht Menschenkraft Könne_n_ die Wirre_n_ dieses Landes schlichte_n_."