In the movement cycle of the simple sounds there is a perfect uniformity of the movements of the positive and negative sets of muscles from unit group to unit group.  But in verse, the movements of the motor apparatus are very complicated.  Certain combinations require more time for execution; but if this variation in the details of the movement does not break the series of motor cues, or so delay the movements as to produce a feeling of strain, the unit groups are felt to be alike.  We have no means of judging their temporal equality, even if we cared to judge of it.  It is a mistake, however, to say that time relations (’quantity’) play no part in modern verse, for the phases of the movement cycle have certain duration relations which can be varied only within limits.

Extreme caution is necessary in drawing conclusions as to the nature of verse from work with scanned nonsense syllables or with mechanical clicks.  It is safe to say that verse is rhythmic, and, if rhythm depends on a certain regularity of movements, that verse will show such movements.  It will of course use the widest variation possible in the matter of accents, lags, dynamic forms, and lengths of sonant and element depending on emphasis.  The character of the verse as it appears on the page may not be the character of the verse as it is actually read.  The verses may be arbitrarily united or divided.  But in any simple, rhythmic series, like verse, it seems inevitable that there shall be a pause at the end of the real verse, unless some such device as rhyme is used for the larger phrasing.

There is a variety of repetitions in poetry.  There may be a vague, haunting recurrence of a word or phrase, without a definite or symmetrical place in the structure.

Repetition at once attracts attention and tends to become a structural element because of its vividness in the total effect.  There are two ways in which it may enter into the rhythmic structure.  It may become a well-defined refrain, usually of more than one word, repeated at intervals and giving a sense of recognition and possibly of completeness, or it may be so correlated that the verses are bound together and occur in groups or pairs.  Rhyme is a highly specialized form of such recurrence.

The introduction of rhyme into verse must affect the verse in two directions.

It makes one element in the time values, viz., the verse pause, much more flexible and favors ‘run on’ form of verses; it is an important factor in building larger unities; it correlates verses, and contributes definite ‘Gestaltqualitaeten’ which make possible the recognition of structure and the control of the larger movements which determine this structure.  Thus it gives plasticity and variety to the verse.