This essay begins, somewhat like the form of Swinburne’s devising that is its subject, at the end, which is to say at the ‘Envoi’ concluding A Century of Roundels on its last and hundredth page (Swinburne 1883, 100; 1904, 5.193): Fly, white butterflies, out to sea, Frail pale wings for the winds to try, Small white wings that we scarce can see Fly. Here and there may a chance-caught eye Note in a score of...