tone that is not sweeter when it embodies a lovely melody; there is no emotion that is not apotheosized by association with others in a harmonious whole, or that does not defeat itself when it stands out single, and will not merge itself in the organism. No music is wholly devoid of any one of the three values; but the greatest music uses the first two only as the materials of the third. It is easy to see, however, that supreme as the æsthetic value of music may be, men could arrive at an appreciation of it only after a long novitiate and training. To enjoy the sensuous beauty of sweet sounds one needs only ears; to be moved by melodies and rhythms that strongly suggest those vocal utterances and bodily motions which are the natural avenues of emotion, requires but a slightly more complex appreciative mechanism, the mechanism of organic sensations and their associations in the regions of naïve feeling; but to perceive the manifold inter-relationship, and the final unity, of groups of tones combined together by relations in pitch and in time, one needs a keen ear, an awakened memory, a capacity for tracing unity under the mask of variety,--in a word, a thoroughly trained and concentrated mind. Musical art could reach a stage in which all three of its values were associated in due proportion and proper adjustment, only through a gradual progress beginning with stages in which it was but the embodiment of sensuous, or at most of sensuous and emotional, values. That it did, as a matter of fact, go through these evolutionary phases, can be demonstrated by a brief and summary account of the actual periods in its history.