It has been suggested to me that the usefulness of my little book would be enlarged if I were to add an appendix containing some application to practical work of the physiological laws already explained. This I have endeavoured to do in the following chapter, and I trust the simplicity of the directions will enable the reader to carry out my instructions, to vary them, and to enlarge upon them according to circumstances. HINTS ON TEACHING. One of the most important lessons taught us by the study of Vocal Physiology is the correct method of breathing and of obtaining control over the respiratory muscles. I will now give a few exercises for this purpose. Divest yourself of any article of clothing which at all interferes with the freedom of the waist. Lie down flat on your back. Place one hand lightly on the abdomen and the other upon the lower ribs. Inhale, through the nostrils, slowly, deeply, and evenly, without interruption or jerking. If this is done properly the abdomen will, gradually and without any trembling movement, increase in size, and the lower ribs will expand sideways, while the upper part of the chest and the collar-bones remain undisturbed. Now hold the breath, _not_ by shutting the glottis, but by keeping the midriff down and the chest walls extended, and count four mentally, at the rate of sixty per minute. Then let the breath go _suddenly_. The result of this will be a flying up of the midriff, and a falling down of the ribs; in other words, there will be a collapse of the lower part of the body. This collapse may not at first be very distinct, as the extension has probably been insufficient; but both will become more and more perfect as the result of continued practice. Let it be clearly understood: The _in_spiration is to be slow and deep, the _ex_piration sudden and complete. In _in_spiration the abdomen and the lower part of the chest expand, and in _ex_piration they collapse. The time of holding the breath is not, at the outset, to exceed four seconds, and the student must never, on any account, fatigue himself with these exercises; they may, however, be frequently repeated at intervals. It will be found by occasional trials upon the spirometer that the breathing capacity increases with these exercises. The process of abdominal respiration becomes easy and no longer requires constant watchfulness, and the student will soon be able to carry it on, not only lying down, but while he is standing or walking, though not at once with the same ease. He must now, for a time, be careful to see that he has the same physical sensations in breathing which he noticed while making his first experiment when lying down; and he must exercise special care when running, going upstairs, &c., and, of course, in speaking or singing.