"Yes, outside," said Leighton bitterly. "But first it is inside." Miranda's confident assertion was worth considering. That there might be--that there probably was--some subterranean connection between the cave and the lake--even if the former did come from fire--was a plausible theory. As he went over the matter in his own mind, Leighton's respect for Miranda's common sense jumped from zero to a comparatively high figure. But he was not convinced. "You forget; we are above the level of the lake," he argued. "That is true," agreed the doctor, who, in the meantime, bottle in hand, had been nervously walking about, peering into the darkness that surrounded them. "Yes, that is true. We come in over there; and always we walk up, up. The lake is always below. This path it never go down. But here--aha! Caramba!--is one other path--and it go down." Miranda's voice shrilled with excitement. He was elated with the importance of his discovery. And it was important. The spot they had chosen for their lunch was the furthest point they had reached in their explorations, the point where Miranda had turned back to take Mrs. Quayle out of the cave and where they had last seen Raoul Arthur. It was marked by a huge pyramidal rock rising from the floor of the cave. Along one side of this rock the path they had followed went on indefinitely, in a gradual upward incline. It was to the other side that Miranda eagerly called attention. Placing his bottle of claret down on the rock beside him, he got on his knees and, with his nose almost touching the ground, made a minute study of the floor of the cave. Even Andrew felt the contagion of the doctor's excitement. Fruits, bollos, cassavas were abandoned pell mell as one and all scrambled to their feet eager to find out what new puzzle Miranda had managed to pick up. The light from their lamps cast huge, uncertain shadows on the irregular masses of rock that everywhere blocked the view. At first there was nothing to be seen that differed essentially from what they had grown accustomed to in this subterranean world. There was the same chaos of jagged pinnacles and bowlders, the same display of irresistible energy that had been let loose and played itself out here ages ago. But in the midst of it all, zigzagging through this maze of dusty forms, there was the new path announced by Miranda. It led away from the central rock, or pillar, where they had taken their lunch, and formed an acute angle with the path they had already traversed. It was not so plainly marked as the latter, and appeared little more than a rift among the rocks that strewed the floor of the cave. But it was a path, there was no mistaking that. Among the evidences that it had been recently used was one that particularly delighted Miranda and justified his prolonged microscopic examination of the path itself--the footprints of a man wearing, not sandals, but shoes. "Raoul Arthur!" exclaimed Leighton. "Perhaps," agreed Miranda.