"It once might have been, once only," is the refrain of the lover's regret in Browning, as "once and only once and for one only" is the keynote of his triumph. In the contours of event and circumstance, as in those of material objects, he loves jagged angularity, not harmonious curve. "Our interest's in the dangerous edge of things,"-- "The honest thief, the tender murderer, The superstitious atheist;" where an alien strain violently crosses the natural course of kind; and these are only extreme examples of the abnormal nature which always allured and detained Browning's imagination, though it was not always the source of its highest achievement. Ivánovitch, executing justice under the forms of murder, Caponsacchi, executing mercy under the forms of an elopement, the savagery of Halbert and Hob unnerved by an abrupt reminiscence,--it is in these suggestive and pregnant situations, at the meeting-points of apparently irreconcilable classes and kinds, that Browning habitually found or placed those of his characters who represent any class or kind at all. [Footnote 117: _By the Fireside_.] The exploring, in-and-out scrutinising instincts of Browning's imagination equally left their vivid impress upon his treatment of character. If the sharp nodosities of character caught his eye, its mysterious recesses and labyrinthine alleys allured his curiosity; this lover of "clefts," this pryer among tangled locks and into the depths of flower-bells, peered into all the nooks and chambers of the soul with inexhaustible enterprise. It is hard to deny that even _The Ring and the Book_ itself suffers something from the unflagging zest with which the poet pursues all the windings of popular speculation, all the fretwork of Angelo de Hyacinthis's forensic and domestic futilities. The poem is a great poetic Mansion, with many chambers, and he will lead us sooner or later to its inner shrine; but on the way there are "closets to search and alcoves to importune,"-- "The day wears, And door succeeds door, We try the fresh fortune, Range the wide house from the wing to the centre."