There is no reason why a metrically 5-stress line should not contain only two prose stresses, but examples are of course rare. Such an unusual rhythm would be seldom demanded. The phrase "acidulation of perversity" might do, for it is easily modulated to the metrical form. Occasionally, as in the last line of Christina Rossetti's sonnet quoted on pages 120 f., a series of monosyllables with almost level inflection will reduce the prose emphasis of a line and force attention on the important words—
Than that you should remember and be sad.
A better example is Shelley's
A sepulchre for its eternity.
Epipsychidion, 173.
In direct contrast to these lines whose effectiveness springs from a lack of the normal quantity of stress are those which are metrically overweighted. A single stressed monosyllable, supported or unsupported by a pause, may occupy the place of a whole rhythmic beat, or it may be compressed to the value of a theoretically unstressed element. Thus Milton's well-known line—
Rocks, caves, lakes, fens, bogs, dens, and shades of death.
Paradise Lost, II, 621.
might if it stood by itself equally well be taken as an 8-stress or as a 5-stress line; and obviously in a blank verse context it produces a very marked retardation of the tempo. No one would dream of reading it in the same space of time as the rapid line which just precedes it and to which it stands in such striking contrast—
O'er many a frozen, many a fiery Alp.
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