Rees, shaking and shivering with an odd feeling of having been very near the Great End, peered down. He could see nothing. There was a cavernous depth of blackness below, but he could tell neither its width nor its height, for his light was waning rapidly. Suddenly he caught sight of something which roused him again to a frantic pitch of do-all, dare-all curiosity. It was a rope attached to an iron staple at his feet, and hanging down. The temptation to go further was now irresistible. Throwing himself first into a sitting position, with his legs hanging over the rock, he tried the rope, giving it a tug with his disengaged hand. It seemed firm. That decided him. He fastened his lantern to the rope which was tied round his waist, and seizing the other, swung himself over and began descending, hand under hand. He had not gone down more than a couple of yards, however, when the rope, which was old and rotten, gave way, and he was thrown to the ground. Luckily, this was only a couple of feet or so below him, and he picked himself up at once, unhurt, with his lantern unextinguished. As he did so, he noticed a strange sound like heavy hailstones falling. Beginning as he touched the ground, it continued for a few moments after, growing gradually fainter. This, he found, proceeded from the walls, which were here only just far enough apart to allow him to pass without touching them. The disturbance he made in the still air had caused hundreds of little flat flakes of stone to crumble off the rocky sides and to fall to the ground. He was now, he felt sure, going under the river; for the passage went straight forward without slope or curve. He was conscious, as he hurried on, of a strange acrid smell, quite unlike the damp heavy fumes which, in spite of his precautions, had faintly reached his nostrils in the stage above. Here it was dry--strangely dry--with an atmosphere which, although not hot, seemed to parch the flesh as he passed. But, in the meantime, breathing through the tube was becoming difficult, and a mad impatience seized him when he found that there was a sudden turn in the passage just in front of him, while he had come so close to the end of the tubing that the length left would not allow him to pass the corner. If he went carefully, however, he thought he could, by the last rays of his dying candle, manage to look round. Very cautiously he now moved; two steps more; yes, he could just do it. The tube was stretched to its utmost length; already he felt himself half suffocated, as if it had caught on something. But as he reached the corner, and held the little flickering light up to see what it led to, his eyes fell on a sight which would have stopped his breath with horror even if he had been breathing free air. Seated on a chest against the wall, leaning his head back, and meeting Rees Pennant’s stare of dismay with eyes wide open and horror-struck as his own, was a lean and shrivelled man. CHAPTER XI.