Soon to the runner the scene changed. The trees crowded each other less closely and there was less of denned pathway. There came something of an ascent and he breasted it, though less swiftly, for, despite the impelling force, nature had claims, and muscles were wearying of their work. Fewer and fewer grew the trees. He knew that he was where there was now a sweep of rocky highlands and that he was not far from the Fire Country, of which Old Mok had so often told him. He burst into the open, and as he came out under the stars, which he could see again, he heard an ominous whine, too near, and a distant howl behind him. A wolf pack wanted him. He shuddered as he ran. The life instinct was fully awakened in him now, as the dread from which he had run became more distant. Had he heard that close whine and distant howl before he fairly reached the open he would have sought a treetop for refuge. Now it was too late. He must run ahead blindly across the treeless space for such harborage as might come. Far ahead of him he could see light, the light of fire, reaching out toward him through the darkness. He was panting and wearied, but the sounds behind him were spur enough to bring the nearly dead to life. He bowed his head and ran with such effort as he had never made before in all his wild and daring existence. The wolves of the time, greater, swifter and fiercer than the gaunt gray wolves of northern latitudes and historic times, ran well, but so did contemporaneous man run well, and the chase was hard. With his life to save, Ab swept panting over the rocky ground with a swiftness begotten of the grand last effort of remaining strength, running straight toward the light, while the wolf pack, now gathered, hurled itself from the wood behind and followed swiftly and relentlessly. Ever before the man shone the light more brightly; ever behind him became more distinct the sound made by the following pack. It was a dire strait for the running man. He was no longer thinking of what he had lately done. He ran. [Illustration: WITH A GREAT LEAP HE WENT AT AND THROUGH THE CURLING CREST OF THE YELLOW FLAME] The light he had seen extended as he neared it into what looked like a great fence of flame lying across his way. There were gaps in the fence where the flame, still continuous, was not so high as elsewhere. He did not hesitate. He ran straight ahead. Closer and closer behind him crowded the pursuing wolves, and straight at the flame he ran. There was one chance in many, he thought, and he took it without hesitation. Close before him now loomed the wall of flame. Close behind him slavering jaws were working in anticipation, and there was a strain for the last rush. There was no alternative. Straight at the fire wall where it was lowest rushed Ab, and with a great leap he went at and through the curling crest of the yellow flame!