Begin with the nares or humming tone, giving it on as many different notes of the scale as can be easily reached. Practise the scale gliding from one note to another while maintaining the pure tone. Practise gliding in the form of inflection, or slide, from one extreme of pitch to another. This may be given with variations, according to the ability of the student to control his voice with evenness and to maintain that pure smoothness of gradation in quality which permits no break or interruption in gliding from one pitch to another. These varieties of practice in slides and scales should be introduced with the practice of various elements of speech, as well as with the humming tone. The different vowels should be so used. Selections for practice should be chosen which contain much variety of thought and feeling and are smooth in movement. For instance, Tennyson's "Song of the Brook," "The Bugle Song," practised with the introduction of the bugle notes and their echoes, and various other selections of a musical and attractive nature, may be adapted to this practice by simply exaggerating the slides which one would naturally make in bringing out the meaning. No extravagant or unwarrantable inflections which will mar the expression of the thought should be permitted, but it is quite desirable to gradually extend the range of the inflections, if one still maintains in the practice that common sense which will leave the expression in perfect symmetry when the extra effort made for inflection shall have been withdrawn. Though it is sometimes desirable to exaggerate one element, even to the sacrifice of others, it is never necessary to introduce false notes, the effect of which may remain as a limitation upon the expression of the selection used.
Other things being equal, the volume of voice used measures the value that the mind puts upon the thought. Of course the expression of this value is modified and characterized by the nature of the thing spoken of. For example, one would express the value of the ocean with a different quality from that which would be used in expressing the value of something exquisitely delicate. All elements of expression modify each other, so that no mere rule can cover all cases. Volume is not always expressed in the form of extension of power, but is frequently manifested in the form of intensity or compressed volume. It is scarcely necessary to explain the difference between the expression of mere vital power in the voice and that manifestation of the will which gives the impression of directed energy. The will determines, and the impetus of the thought is measured by, the adjustment of volume. Vitality is expressed in radiation; will is expressed in focus.