Cautiously they crept along the canyon, pausing occasionally to listen for any sound of their foes. But the underworld might have been deserted for all they could hear. Never had the silence been more profound. The cliffs on either side rose steep and inaccessible as the wall of a house. Not a crevice or foothold of any description presented itself in the face of the towering walls. As straight were they as though the hills had been split asunder by the stroke of some giant sword. Here and there, at the base of the cliffs, grew a solitary fungus or a cluster of puff-balls, the weird, bloated forms of these latter betraying nothing of their terrible explosive power. For an hour, perhaps, the three men moved forward, plunging deeper and deeper into the heart of the hills, and still there came no sound from the wolf-men. They had almost begun to believe--incredible though it seemed--that they had shaken off their pursuers. What else could be the meaning of their inaction? Had they known of the _coup_ which, even then, the crafty Nordhu was preparing against them, they would have lost little time in making their way out of the gorge. As it was, they took their ease, resting at intervals during their journey. Their future movements they had not decided upon, their time being fully taken up with the exchange of their experiences. The loss of the _Seal_ seemed to the professor an overwhelming blow. “We are lost indeed without the vessel,” he remarked gloomily. “I guess if there’s a road out of these infernal regions, we shouldn’t ha’ struck it with the _Seal,”_ was Haverly’s sharp answer; “but that ain’t the trouble at present. You say you’ve seen nothin’ of Garth?” “Not a sign,” was the reply. “Wal, that’s a licker! Say, Seymour, what do you make of it?” “He’s either been murdered by the savages or else he has escaped,” answered the baronet. “Put your money on the last of them two; I calculate they’d hardly be likely to knock him on the head, seeing as how all prisoners are reserved for spider-meat. Anyway, we’ll assume he’s got clear, though what he’ll do now the _Seal’s_ gone, Heaven alone knows!” “What of Wilson?” asked Mervyn suddenly. “When we know his fate,” returned Seymour, “the mystery of the _Seal’s_ disappearance will be a mystery no longer.” Hereafter silence fell upon the trio. Each man’s thoughts were busy with the things of the future. Would they ever find a way out of this underworld, or were they doomed to wander in its ghostly wilds until death released them? At the moment their prospect was not an alluring one! Without any settled plan for the future, save to put as great a distance as possible between themselves and the wolf-men, they seemed helpless. Haverly’s active mind revolved all the expedients which presented themselves, yet, even to him, the case seemed almost hopeless. “Say, professor,” he cried, breaking the long silence, “ain’t you got----”