"We'd better keep a sharp lookout," I said suddenly. "Remember, a demon doesn't have to come along the ledge to get at us." "I have not forgotten that, Bill; but we are armed." As I believe was made sufficiently obvious, the crossing of those places where the ledge narrowed to the width of but a yard or so had been no pleasant matter; but, during this the return, the thing assumed (in my imagination, at any rate) an aspect truly sinister. That we were being watched both of us regarded as certain. That we might at any moment find a demon or a dozen demons driving at us--well, that was a possibility which never left our thoughts for one single second. And, in those narrow places, where the ledge contracted to a mere ribbon of rock, it was all that one wanted to do to hug the wall and make sure of his footing. A frightful place truly in which to meet, even with a revolver, the attack of but one of those winged monsters; and we might find ourselves attacked by a dozen. It can easily be imagined, then, the relief which I felt when we had passed the last narrow spot, though, forsooth, we might be going towards something far more dangerous than anything that we had left behind us. But the angel had gone down, and where a woman could go, there, I told myself in masculine pride, could we also. "That is," I subjoined, "supposing that we do not meet ape-bats or something more terrible." At length we stood once more at the mouth of the gallery. And scarcely had we stopped there when an unpleasant thing flashed into my thoughts--which, as it was, resembled anything but the rainbow. "Great Heavens!" I cried, peering into the tunnel, which, at the distance of only thirty feet or so, gave a sudden turn to the right. Something could be in there, very close to us and yet unseen. "What is it, Bill?" "Could those lights that we saw have been _here_? Are they waiting in there to dog our steps or to do something worse?" Rhodes, peering into the gallery with a curious, half-vacuous expression on his face, made no reply. "Well," I queried, "what do you think of it? We could not tell where those lights were, how far away--anything." "I don't think that they were here," Milton Rhodes returned. "I think that they were much farther down and _on the other side_." "On the other side? How on earth could any one cross that chasm?" "We don't know what it is like down there. And, of course, I don't _know_ that the lights were on the other side. But I believe that they were." A silence ensued, which at length I broke: "What is the next thing on the programme?" "Make our way down the ledge. That is the only way there is for us to go. But first we'll try a little finesse." He took a position in the mouth of the tunnel, one that permitted him to look down the great cavern. He signed to me to follow suit, and, when I stood at his side, he said: "Off go the lights."