That thought was enough for Og. He must find his father. He must risk any dangers or any of the night terrors to find Wab. Hastily he made two fire brands and ignited them. Then, arming himself also with stone hammer and a long flint knife, he called to the wolf dogs. The animals he quickly made to understand just what was wanted of them, and when they did know their mission they bounded forward despite the fact that they were tired, and with noses to the ground followed the trail of Wab and Gog, while Og swung along behind them at a remarkably swift pace despite the fact that he too was tired from his day’s efforts.

Into the black fastness of the forest they plunged, their only light being the glimmer from Og’s torches. Despite his courage and the importance of his mission, Og could not stifle the natural, instinctive fear that possessed him as he dodged in and out among the trees, his eyes and ears alert for any signs of danger.

Southward they swung toward the mountain range that cut their valley off from the valley of the warm lands beyond, and presently they began to mount the thickly wooded slopes. Strange night noises they heard aplenty. To most of these the wolf dogs paid little heed, but when from afar they heard the terrifying roar of a cave tiger and the answering challenge of some wandering cave leopard, the hair on their backs bristled. So did that of Og, and he actually trembled with fear despite the stoutness of his heart. This traveling at night through the forest was a fearsome thing to do, and time and again he was tempted to seek the shelter of some huge bowlder, and build a great fire beside which to spend the remainder of the night.

But the thoughts of his father somewhere here in the terrible forest, and without fire (for Og knew that Wab, or Gog either, would never travel with a fire in his hand the way he did), spurred the hairy boy on to move faster and put aside the desire to build a big protective fire at least until he had found his father.

Upward on the mountain side they climbed, the wolf dogs following closely the trail that Gog and Wab had taken. On and on they pushed, soon panting and out of breath. Og’s lungs were pumping, too, and he sucked in air in great gasps; but still he climbed and kept pace with the hurrying dogs.

Soon they reached the gently rolling summit, where if it had been daylight they could have looked into the valley below. But as they halted there a brief space to catch their breaths, Og gave a loud and startled grunt, for from below him, and in the direction the wolf dogs were straining to go, rolled up to him a loud, booming sound. Og had little difficulty in recognizing it as the war noise of his old captors, the tree people. And this all added to his feeling of alarm, for he could tell by the volume of the sound that there were many ape-like men below there in the valley and they were very angry.

If Og and the wolf dogs had hurried before now, they fairly raced through the blackness of the forest. Down the slope they crashed, the booming noise growing louder and nearer at every step. And as they plunged forward both Og and the wolf dogs grew more and more excited, until presently the hairy boy found himself beating his chest with one clenched hand and roaring at the top of his voice while the dogs set up a fierce barking that added to the general din of the occasion.

Suddenly the booming sound, which now seemed close at hand, stopped and Og became aware of big forms swinging among the branches of the trees. Sticks came pelting down out of the blackness, too, and he could see myriads of green eyes glowing at him and he could hear teeth gnashed and clicked together. Still he rushed forward until presently he broke into a clearing where was massed a horde of milling, chattering tree people.

His coming, however, caused panic and consternation among them. They saw his flaming firebrand and they scattered and fell back. And the parting of the mass left a lane open that extended to a huge rock where, with their backs to this wall, stood Gog and Wab, each with a blood-smeared stone hammer clutched in his hand while before them laid a pile of writhing bodies of tree people. Og could see at a glance that it had been a terrible battle and that Gog and Wab were all but done for. Indeed, Gog, dripping blood from a hundred terrible wounds, staggered and swayed as he stood there, and Wab had to lean against the rock for support.