It has already been observed that Mr. Lanier did good service in emphasizing the analogy between music and poetry, but that he carried the analogy too far. It may, therefore, be worth while to consider at just this point the elements of likeness and of difference in the two forms of art. Both are forms of _rhythmical_ art: music and verse are alike rhythmical sound. Lanier showed with sufficient certainty that rhythm is dependent upon both _time_ and _accent_. He said, to be sure, that "time is _the_ essential" element;[50] but this does not seem to have been altogether what he meant, for he himself pointed out that the ear insistently marks off time-elements by the sense of variation of stress, even when there is no real variation, as in the tick-tack of the clock. He also pointed out that accent marks the rhythm of music quite as truly as that of verse, the rule being that ordinarily the first note of each measure shall receive a special stress. It seems, then, that the rhythm of music is based on the recurrence of accented sounds at equal time-intervals. The same thing is true of the rhythm of verse. For every kind of metre there is a normal verse-rhythm which is present in the mind as the basis on which the verse is built up, no matter how many variations may constantly occur. This normal rhythm is formed by a succession of accents at exactly equal time-intervals,[51] such as can be marked off by a metronome, or by the mechanical beating of the foot on the floor. We realize that the verse as commonly read frequently departs from this regularity of intervals; but without the regularity as a norm to which to refer it, we should not recognize it as verse. The normal accent-interval we call a "foot."