Day and night Tarzan of the Apes raced through the primeval forest toward the ruined city in which he was positive the woman he loved lay either a prisoner or dead.

In a day and a night he covered the same distance that the fifty frightful men had taken the better part of a week to traverse, for Tarzan of the Apes traveled along the middle terrace high above the tangled obstacles that impede progress upon the ground.

The story the young bull ape had told made it clear to him that the girl captive had been Jane Porter, for there was not another small white “she” in all the jungle. The “bulls” he had recognized from the ape’s crude description as the grotesque parodies upon humanity who inhabit the ruins of Opar. And the girl’s fate he could picture as plainly as though he were an eyewitness to it. When they would lay her across that trim altar he could not guess, but that her dear, frail body would eventually find its way there he was confident.

But, finally, after what seemed long ages to the impatient ape-man, he topped the barrier cliffs that hemmed the desolate valley, and below him lay the grim and awful ruins of the now hideous city of Opar. At a rapid trot he started across the dry and dusty, bowlder-strewn ground toward the goal of his desires.

Would he be in time to rescue? He hoped against hope. At least he could be revenged, and in his wrath it seemed to him that he was equal to the task of wiping out the entire population of that terrible city. It was nearly noon when he reached the great bowlder at the top of which terminated the secret passage to the pits beneath the city. Like a cat he scaled the precipitous sides of the frowning granite kopje. A moment later he was running through the darkness of the long, straight tunnel that led to the treasure vault. Through this he passed, then on and on until at last he came to the well-like shaft upon the opposite side of which lay the dungeon with the false wall.

As he paused a moment upon the brink of the well a faint sound came to him through the opening above. His quick ears caught and translated it—it was the dance of death that preceded a sacrifice, and the singsong ritual of the high priestess. He could even recognize the woman’s voice. Could it be that the ceremony marked the very thing he had so hastened to prevent? A wave of horror swept over him. Was he, after all, to be just a moment too late? Like a frightened deer he leaped across the narrow chasm to the continuation of the passage beyond. At the false wall he tore like one possessed to demolish the barrier that confronted him—with giant muscles he forced the opening, thrusting his head and shoulders through the first small hole he made, and carrying the balance of the wall with him, to clatter resoundingly upon the cement floor of the dungeon.

With a single leap he cleared the length of the chamber and threw himself against the ancient door. But here he stopped. The mighty bars upon the other side were proof even against such muscles as his. It needed but a moment’s effort to convince him of the futility of endeavoring to force that impregnable barrier. There was but one other way, and that led back through the long tunnels to the bowlder a mile beyond the city’s walls, and then back across the open as he had come to the city first with his Waziri.

He realized that to retrace his steps and enter the city from above ground would mean that he would be too late to save the girl, if it were indeed she who lay upon the sacrificial altar above him. But there seemed no other way, and so he turned and ran swiftly back into the passageway beyond the broken wall. At the well he heard again the monotonous voice of the high priestess, and, as he glanced aloft, the opening, twenty feet above, seemed so near that he was tempted to leap for it in a mad endeavor to reach the inner courtyard that lay so near.

If he could but get one end of his grass rope caught upon some projection at the top of that tantalizing aperture! In the instant’s pause and thought an idea occurred to him. He would attempt it. Turning back to the tumbled wall, he seized one of the large, flat slabs that had composed it. Hastily making one end of his rope fast to the piece of granite, he returned to the shaft, and, coiling the balance of the rope on the floor beside him, the ape-man took the heavy slab in both hands, and, swinging it several times to get the distance and the direction fixed, he let the weight fly up at a slight angle, so that, instead of falling straight back into the shaft again, it grazed the far edge, tumbling over into the court beyond.

Tarzan dragged for a moment upon the slack end of the rope until he felt that the stone was lodged with fair security at the shaft’s top, then he swung out over the black depths beneath. The moment his full weight came upon the rope he felt it slip from above. He waited there in awful suspense as it dropped in little jerks, inch by inch. The stone was being dragged up the outside of the masonry surrounding the top of the shaft—would it catch at the very edge, or would his weight drag it over to fall upon him as he hurtled into the unknown depths below?