Suddenly flashed on her a wild desire.
Tennyson, Lancelot and Elaine, 355.
And the following line (Comus, 8) contains an extra syllable at the end, one in the middle, and also a trisyllabic effect at the beginning—
Strive to keep up a frail and feverish being.
This last phenomenon, the trisyllabic (or dactylic, or anapestic) effect, is commonly described as an inversion—the 'rule' being given that in certain parts of the line the iamb is inverted and becomes a trochee. This explanation is convenient, but it is open to the objection of inaccuracy. It almost stands to reason that when a rising rhythm is established the sudden reversal of it would produce a harsh discordant effect, would practically destroy the rhythmic movement for the time being. So it is in music, at any rate,[95] whereas it is not so with these 'inverted feet' of verse. Therefore it seems more reasonable to scan such a line as that of Tennyson thus:
‸ Sud | denly flashed | on her | a wild | desire,
and the substitution is simply that of a triple rising (anapestic) for a duple rising (iambic) rhythm in the same time. Sud-is a monosyllabic foot, and the preceding rest is easily accounted for by the pause at the end of the previous line. In fact, this phenomenon is nearly always in immediate proximity to a pause either at the beginning of a line or in the middle. Very common is the movement—
Flashing thick flames, wheel within wheel withdrawn.
Milton, Paradise Lost, VI, 751.
Thou on whose stream, 'mid the steep sky's commotion.
Shelley, Ode to the West Wind.
Or if they sing, 'tis with so dull a cheer
That leaves look pale, dreading the Winter's near.
Shakespeare, Sonnet 97.
Less simple are the following lines from Samson Agonistes—