ECONOMY OF BREATH
The quantity of air taken in with a single inspiration is, in quiet breathing, according to Prof. Mills,[3] from twenty to thirty cubic inches, but this may be increased in the deepest inspiration to about one hundred cubic inches. In forcible expiration about one hundred cubic inches may be expelled, but even then the residual air that cannot be expelled is about one hundred cubic inches.
It is not, however, the quantity of breath inhaled that is significant, it is the amount controlled. Get, therefore, all the breath necessary, and keep it, but without undue effort and without rigidity.
To test the amount of breath used in prolonged vocalization, a person skilled in the art of breathing, after an ordinary inspiration, closed his lips, stopped his nostrils, and began to vocalize. He found that the mouth with distended cheeks held sufficient breath to continue a substantial tone for twenty-three seconds.
While these experiments show that very little amount or force of breath is needed to produce effective tones, the impression must exist in the mind of the performer that there is a free flow of breath through the larynx; otherwise the tone will seem restricted and will be weak. The forced holding back of the breath begets a restraint that has a bad effect on the singer's delivery. While the breath must be controlled, there is such a thing as an exaggerated "breath control" that makes free delivery of the voice impossible.
It is quite possible to overcrowd the lungs with air. Do not, therefore, make the mistake of always taking the largest possible breath. Reserve this for the climaxes, and inhale according to the requirements of the phrase and its dynamics. The constant taking of too much breath is a common mistake, but trying to sing too long on one breath is another.
THE INITIAL USE OF BREATH FORCE
The breath force when properly employed seems to be expended in starting the vibrations in the larynx; the vibrations are then transmitted to the air in the resonance cavities, and there the perfected tone sets the outer air in motion, through which the tone vibrations are conveyed to the ear of the listener.
RESERVE BREATH POWER
The correctly trained singer or speaker will never allow the breath power to be exhausted. Some breath should be taken in at every convenient interval between the words, according to the punctuation, but never between syllables of a word;, this is correct phrasing. In this way the lungs are kept nearly full, and breathing is at its best.