The stresses are nearly even throughout; the meter cannot be accurately described as iambic, trochaic, or anapestic; yet there is a rhythm in the approximate temporal equality of the thought-moments. These verses are, however, rather songs than poems. The failure to distinguish between verses which are songs and those which are poems accounts, I believe, for the extremes to which the musical theory of verse has been carried. Still another element of poetry which allies it to music is the repetition of the thought-content. Why repetition should be musical we already know: music is an art which seeks to draw out and elaborate pure emotion; repetition serves this end by constantly bringing the mind back to dwell upon the same theme. Moreover, repetition involves retardation; for a movement cannot progress rapidly if it has to return upon itself; and this slowness gives time for the full value of a feeling to be worked out. In all the more emotional and lyric poetry we find, therefore, recurrence of theme: the thought is repeated again and again; in new forms, perhaps, yet still the same in essence, successive lines or stanzas taking up the same burden; sometimes there is exact recurrence of thought, as in the refrain. And this repetition in the thought is embodied in a repetition of the elements of the sound-pattern; the wave type is repeated from verse to verse or recurs again and again; there is recurrence of melodic form or parallelism between contrasted melodies in different stanzas; there is tonality of vowel and consonant sounds in rime and assonance and alliteration; there may be an approach to identity in the time-duration of the various units. Parallelism or repetition is the fundamental scheme of such poetry. But between repetition with its retardation of movement and progress towards a goal there is a necessary antagonism; hence in the more dramatic and narrative forms of poetry, although recurrence is never entirely absent, there is less of it, and the movement approximates to that of prose. Emotion demands repetition, but action demands progression. After our analysis of the rhythm of poetry, we are in a position to inquire into what can be expressed through it, and how psychologically this expression can be explained.