Sophistry suggested that it might be the missing girl, Esmay, and certainly she who had walked here was the veiled woman of the temple worshippers; there were the footprints, broader and heavier in appearance, of her companion, and the halting progress of the black-chapped ruffian, who had accompanied them, was also plainly visible. Constans followed the trail at a smart pace, for it was snowing harder than ever, and it would not take long to obliterate the marks. But three blocks farther on the three sets of footprints suddenly turned at right angles to the sidewalk and disappeared. A mystery whose solution should have been apparent at once from the wheel-tracks parallel with the curb, but for a minute or two Constans did not realize their true nature. The ordinary vehicle in use among the House People was a springless cart, whose wheels were simply sections of an elm-tree butt, and these primitive constructions creaked horribly upon their axles, unless liberally greased, and left a track six inches or more in width. It is not surprising, then, that Constans was momentarily puzzled by the narrow, delicately lined marks that betokened the passage of a real carriage. For while Doom contained many examples of the ancient coach-builder's skill, they were not in general use. The old Dom Gillian occasionally employed a carriage in taking the air--at least, so Ulick had told him, but Constans had never seen it. For all that the check was but a momentary one; his wits had been sharpened by use, and now they helped him to the truth. He ran on at top speed. A course of a mile or more and he was entering a poorer part of the city a little north of east and close to the shore of the Lesser river. It was a region of tenement dwellings, a huddle of nondescript buildings, flanked by huge factories and sprawling coal and lumber yards--an unpromising region, surely, in which to look for Master Quinton Edge's particular retreat. And yet it would have marked the subtlety of the man to have set his secret here, where it would have been at once so easily seen and overlooked. Every labyrinth has its clew, but the fugitive walks safely in a crowd. The wheel-tracks turned sharply to the right, going straight down a side street to the river-front. On the left were the ruins of one of the ancient plants for the manufacture of illuminating gas. The yard was but a wilderness of rusty iron tanks and fallen bricks; surely there was nothing here to interest.