For “Porphyria’s Lover,” Browning used a rather unusual rhyme scheme: ABABB, which repeats with new A and B rhymes every five lines. Consider lines 1–5:

     The rain set early in to-night,
            The sullen wind was soon
awake,
     It tore the elm-tops down for spite,
            And did its worst to vex the
lake:
            I listened with heart fit to
break.

As indicated here, the poem’s rhymes tend to be exact and to fall on the final syllable of each line, which is very typical. But what’s atypical about the rhyme has to do with the pattern itself. That is, it has to do with the way it at once approximates the rhyme scheme of traditional ballad measure, and yet deviates from that rhyme scheme by adding a fifth rhyme. Traditionally, iambic tetrameter and an ABAB rhyme scheme work well together to form ballad lyrics. The rhyme scheme creates distinct units of meaning, even as the driving meter helps push the song’s narrative forward. But in “Porphyria’s Lover,” the extra B rhyme at the end of each stanza throws everything off, creating the impression of an off-kilter ballad that never quite settles into a comfortable rhythm. The awkwardness of this rhyme scheme has a powerful effect, since it subtly underscores the speaker’s disturbed mental state. For all that he tries to present himself as reasonable and balanced, the persistent imbalance of the poem’s rhyme scheme repeatedly undermines him.