Small an organ as is the larynx it is through it the energy of the expiratory act is transmitted effectively or the reverse to the all-important resonance chambers. This should be so done that there is no waste; in other words, that there be perfect co-ordination between the breathing and the laryngeal mechanism. The vocal bands must be so related in function to the expiratory mechanism that the outgoing blast of air shall be as effective as possible. There must be no waste of power--_i.e._, of the expiratory blast through escape of air that accomplishes no purpose. The blast must be so applied to the vocal bands, or, in other words, they must be so adapted to the blast that there is no waste of energy. If the bands approximate a little too late there is waste of breath power. The bands must further so beat the air of the resonance chambers as to get the greatest possible result with the least possible expenditure of energy. As all these co-ordinations imply the action of many muscles in a related way, it is plain that intelligent and prolonged training is necessary; and if our scientific knowledge had no other result than to establish such a conviction on a sure basis it would be well worth while; but it is a light unto the feet of the student and teacher at every step, only it must be a clear light, not one seen through a mental haze. If there be failure the fault must not be set down to science but to ourselves. It is ever to be borne in mind that when anything is done in the right way not only is there no pain, unpleasant feeling or evil after-effects, but when real skill has been attained through training, the result is accomplished with a sense of ease and all the accompanying feelings are agreeable. The singer need not know that he has a throat by any disagreeable reminder. At the same time a function may be correctly discharged but continued too long, so that weariness or positive fatigue with some evil consequences may follow. Fatigue always implies more or less poisoning of the system. Of the resonance chambers, the mouth cavity, the pharyngeal cavity and the naso-pharynx, which may both be regarded as a part of the mouth cavity, and the nasal chambers, the latter may be considered the least variable in shape; nevertheless they can, by means of the soft palate, be to a large extent shut off from the other parts of this series of chambers. The means by which the size and shape of the resonance chambers can be varied are chiefly the soft palate and the tongue, the latter being of the greatest importance. The changes in the shape of the mouth cavity necessary for the formation of vowels are due chiefly to the movements of the tongue, and the tongue is more largely concerned in the utterance of consonants than any other moveable part of the upper voice mechanism.