The massive span, which had seemed so solid a structure viewed from the gorge, now appeared a very flimsy affair, dwarfed to nothingness by the stupendous dimensions of the great fire gulf. With their eyes fixed upon the giant form of their guide, the three comrades moved on as steadfastly as possible. Over the vast, vibrating sheet of metal that formed the drawbridge they tramped, and glad indeed were they when they had crossed the last span, and their feet touched solid ground. Here the Ayuti dismounted and strode to where a great lever projected from the masonry of the bridge. This he pulled over, and instantly, with a clanging rattle, the drawbridge swung upward into place. “Now that your foes are all destroyed,” he remarked, turning to the baronet, “Nordhu, the priest, will not know whether ye have escaped or no.” But he was wrong; for, as the party once more moved on, a wolf-man crept from his hiding place amid the rocks on the opposite side of the gorge. A moment he stood there in the glare, shaking his spear menacingly towards the retreating figures of the fugitives, then turned and vanished into the gloom of the defile. Forward went the adventurers, the glow from the fire gulf growing fainter as they advanced, until the towers and walls of a city loomed before them through the twilight. The sight aroused the interest of the scientist. Hitherto he had moved in an apathetic manner, very different from his usual brisk style. His nerves had received so rude a shock that he was as yet scarcely himself. Even the sight of Chenobi’s monstrous steed--rare though the creature was--had failed to arouse him. But now, with the walls of the mysterious subterranean city within sight, his scientific zeal revived. Instinctively he felt for his note-book, forgetting for the moment that he had lost it in his adventure with the Triceratops. “Don’t worry,” Seymour said, noting his look of disappointment; “I happen to have one on me that will suit you down to the ground.” Forthwith he produced a bulky pocket-book, at sight of which Mervyn’s eyes glistened. “Many thanks!” he cried, taking it, and at once commenced to scribble down a graphic description of the giant elk. Ere long the party passed through a great gateway, the stone gate of which had fallen from its hinges, and now lay crumbling in the dust. On either hand towered the palaces of the Ayutis, now, alas, tottering to decay. Built of some dazzling white stone, they gleamed through the twilight as though bathed in a flood of moonlight; the effect--accentuated by the silence of the whole place--being indescribably weird. The footsteps of the adventurers raised a volley of echoes from the deserted streets as they moved over the pavement, and from ahead at intervals came the muffled baying of hounds.