The gully was some forty feet deep and seemed to average considerably wider. Its sides were smooth and precipitous in some places; in others they were broken. The Very Young Man had been walking some thirty minutes when, as he came abruptly around a sharp bend, he saw before him the most terrifying object he had ever beheld. He stood stock still, fascinated with horror. On the floor of the gully, directly in front of him, lay a gigantic lizard--a reptile hideous, grotesque in its enormity. It was lying motionless, with its jaw, longer than his own body, flat on the ground as though it were sunning itself. Its tail, motionless also, wound out behind it. It was a reptile that by its size--it seemed to the Very Young Man at least thirty feet long--might have been a dinosaur reincarnated out of the dark, mysterious ages of the earth's formation. And yet, even in that moment of horror, the Very Young Man recognized it for what it was--the tiny lizard the Chemist had sent into the valley of the scratch to test his drug! At sight of the Very Young Man the reptile raised its great head. Its tongue licked out hideously; its huge eyes stared unblinking. And then, slowly, hastelessly, it began coming forward, its great feet scratching on the rocks, its tail sliding around a boulder behind it. The Very Young Man waited no longer, but turning, ran back headlong the way he had come. Curiously enough, this new danger, though it terrified, did not confuse him. It was a situation demanding physical action, and with it he found his mind working clearly. He leaped over a rock, half stumbled, recovered himself and dashed onward. A glance over his shoulder showed him the reptile coming around the bend in the gully. It slid forward, crawling over the rocks without effort, still hastelessly, as though leisurely to pick up this prey which it knew could not escape it. The gully here chanced to have smooth, almost perpendicular sides. The Very Young Man saw that he could not climb out; and even if he could, he knew that the reptile would go up the sides as easily as along the floor. It had been over a hundred feet from him when he first saw it. Now it was less than half that distance and gaining rapidly. For an instant the Very Young Man slackened his flight. To run on would be futile. The reptile would overtake him any moment; even now he knew that with a sudden spring it could land upon him. A cross rift at right angles in the wall came into sight--a break in the rock as though it had been riven apart by some gigantic wedge. It was as deep as the gully itself and just wide enough to admit the passage of the Very Young Man's body. He darted into it; and heard behind him the spring of the reptile as it landed at the entrance to the rift into which its huge size barred it from advancing.