rough material, an expulsion of air, in greater or less force; the vocal cords in the larynx, by their approximation. and vibration, give to this material resonance and tone; while it receives its final form, its articulate character, by the modifying action of the tongue, palate, and lips. Each articulation thus represents a certain position of the shaping organs of the mouth, through which a certain kind and amount of material is emitted. A word is composed of a series of such articulations, and implies a succession of changes of position in the mouth-organs, often accompanied by changes in the action of the larynx upon the passing column of air. Thus, for example, in the word friendly. At first, the tips of the upper teeth are pressed upon the edge of the lower lip, and simple breath, not intonated in the larynx, is forced out between the two organs: the rustling thus produced is the f-sound. The teeth and lips are now released from service, and the tip of the tongue is brought near to the roof of the mouth at a point a little way behind the gums; at the same instant, the vocal cords are raised and strained, so that the escaping air sets them in vibration and becomes sonant; tone, instead of mere breath, is expelled; and the sound of r is heard. Next the tongue is moved again; its point is depressed in the mouth, and its middle raised toward the palate, yet not so near but that the sonant breath comes forth freely, giving an opener, a more sonorous and continuable tone than either of the preceding positions yielded: this we call a vowel, short e. Once more the tip of the tongue approaches the upper part of the mouth behind the teeth, and this time forms a close contact there, cutting off all exit of the breath through the oral passage; but the passage of the nose is opened for its escape, and we hear the nasal n. To produce the next sound, d, the only change needed is the closure of the nasal passage; the mouth and nose being both shut, no emission of breath is possible; yet the tone does not cease; breath enough to support for an instant the sonant vibration of the vocal cords is forced up into the closed cavity of the mouth, behind the tongue: were the vibration and tone intermitted during the instant of closure, the sound uttered would be a t, instead of a d. Before the oral cavity is so full
