Burnt after them to the bottomless pit.
Paradise Lost, VI, 866.
In all of these examples the metrical pattern is the same: five consecutive iambs. The modifications illustrate plainly the extraordinary flexibility of language.
Time and Stress. Probably the most disputed point in all prosodic theory is the relative importance of time (duration, syllabic length) and stress (accent) in English verse. Some writers have attempted to explain all the phenomena entirely by stress; others entirely by time. Neither side, of course, has been very successful.[25] The difficulty is partly one of theory and partly one of correct analysis of the facts. Thanks, now, to the attention paid in recent decades by the experimental psychologists to rhythm and metre, we are in a position to reach at least approximate clearness on this vexed point. Since the older theorists have mostly started either from the traditional conceptions of classical prosody or from examination of but a part of the phenomena, their work may be left out of account here. Certainly no great blame attaches to them; they are the Bacons and Harveys and Newtons of metrical science. A more nearly correct analysis of the facts is possible now because with the minutely accurate instruments of the scientists to aid us we need no longer trust to the uncertainties of perception and statement of separate individuals. Of course no one today holds the extreme belief that science explains everything; and of course the scientific experiments on the nature and effect of rhythm must have a starting point in the personal equations of those who have submitted themselves to the scientific tests. With all its patience and thoroughness of investigation, experimental psychology is only now establishing itself. But it does offer, on this one mooted point of versification, invaluable help.
The theory presented in the previous pages states that sound rhythm consists of a succession of points of emphasis separated by equal time divisions. This is the ideal rhythm. When subjected to the conditions of metrical language it suffers two alterations. In the first place, our notions of time are extremely untrustworthy. Days vanish in a moment and they drag like years. Very few of us can estimate correctly the passage of five minutes: syllables are uttered in a few hundredths of a second. We are satisfied with the accuracy shown by an orchestra in keeping time; but if we took a metronome to the concert we should find the orchestra very deficient in its sense of time. The fact is that the orchestra knows better than the metronome, that perfectly accurate time intervals become unpleasantly monotonous, that we rebel at 'mechanical' music. Thus the time divisions of pleasurable rhythm are not mathematically equal, nor even necessarily approximately equal, but are such as are felt to be equal. The second alteration of ideal rhythm is that which results from the conformity of fluid language to its metrical mould. This metrical scheme, based theoretically on equal time units marked by equal stresses, becomes a compromise of uneven stresses and apparently equal time divisions.
Almost every line of verse is a proof of this: both the fact and the explanation are clear when approached from the right angle, and may be tested by carefully prepared statistics. In the following examples the figures beneath each syllable give the time of utterance in tenths and one-hundredths of a second; the figures in parentheses represent pauses.[26] The first, from Paradise Lost, II, 604-614, is in blank verse, with five iambic feet to a line; the second, from Shelley's The Cloud, is apparently irregular, but the basis is clearly anapestic. The ideal rhythm or metrical pattern of the first is
◡ _̷ ◡ _̷ ◡ _̷ ◡ _̷ ◡ _̷
regularly repeated. The ideal rhythm of the second is
◡ ◡ _̷ ◡ ◡ _̷ ◡ ◡ _̷ ◡ ◡ _̷
◡ ◡ _̷ ◡ ◡ _̷ (◡ ◡ _̷)
six times repeated.[27]