When he spoke it was evidently after some little effort to muster his courage. "I knew you of old," he said, "when you ranged the jungle in the country of Mbonga, the chief. I was already a witch-doctor when you slew Kulonga and the others, and when you robbed our huts and our poison pot. At first I did not remember you; but at last I did—the white-skinned ape that lived with the hairy apes and made life miserable in the village of Mbonga, the chief—the forest god—the Munango-Keewati for whom we set food outside our gates and who came and ate it. Tell me before I die—are you man or devil?"

Tarzan laughed. "I am a man," he said.

The old fellow sighed and shook his head. "You have tried to save me from Simba," he said. "For that I shall reward you. I am a great witch-doctor. Listen to me, white man! I see bad days ahead of you. It is writ in my own blood which I have smeared upon my palm. A god greater even than you will rise up and strike you down. Turn back, Munango-Keewati! Turn back before it is too late. Danger lies ahead of you and danger lurks behind; but greater is the danger before. I see—" He paused and drew a long, gasping breath. Then he crumpled into a little, wrinkled heap and died. Tarzan wondered what else he had seen.

It was very late when the ape-man re-entered the boma and lay down among his black warriors. None had seen him go and none saw him return. He thought about the warning of the old witch-doctor before he fell asleep and he thought of it again after he awoke; but he did not turn back for he was unafraid, though had he known what lay in store for one he loved most in all the world he would have flown through the trees to her side and allowed the gold of Opar to remain forever hidden in its forgotten storehouse.

Behind him that morning another white man pondered something he had heard during the night and very nearly did he give up his project and turn back upon his trail. It was Werper, the murderer, who in the still of the night had heard far away upon the trail ahead of him a sound that had filled his cowardly soul with terror—a sound such as he never before had heard in all his life, nor dreamed that such a frightful thing could emanate from the lungs of a God-created creature. He had heard the victory cry of the bull ape as Tarzan had screamed it forth into the face of Goro, the moon, and he had trembled then and hidden his face; and now in the broad light of a new day he trembled again as he recalled it, and would have turned back from the nameless danger the echo of that frightful sound seemed to portend, had he not stood in even greater fear of Achmet Zek, his master.

And so Tarzan of the Apes forged steadily ahead toward Opar's ruined ramparts and behind him slunk Werper, jackal-like, and only God knew what lay in store for each.

At the edge of the desolate valley, overlooking the golden domes and minarets of Opar, Tarzan halted. By night he would go alone to the treasure vault, reconnoitering, for he had determined that caution should mark his every move upon this expedition.

With the coming of night he set forth, and Werper, who had scaled the cliffs alone behind the ape-man's party, and hidden through the day among the rough boulders of the mountain top, slunk stealthily after him. The boulder-strewn plain between the valley's edge and the mighty granite kopje, outside the city's walls, where lay the entrance to the passage-way leading to the treasure vault, gave the Belgian ample cover as he followed Tarzan toward Opar.

He saw the giant ape-man swing himself nimbly up the face of the great rock. Werper, clawing fearfully during the perilous ascent, sweating in terror, almost palsied by fear, but spurred on by avarice, following upward, until at last he stood upon the summit of the rocky hill.

Tarzan was nowhere in sight. For a time Werper hid behind one of the lesser boulders that were scattered over the top of the hill, but, seeing or hearing nothing of the Englishman, he crept from his place of concealment to undertake a systematic search of his surroundings, in the hope that he might discover the location of the treasure in ample time to make his escape before Tarzan returned, for it was the Belgian's desire merely to locate the gold, that, after Tarzan had departed, he might come in safety with his followers and carry away as much as he could transport.

He found the narrow cleft leading downward into the heart of the kopje along well-worn, granite steps. He advanced quite to the dark mouth of the tunnel into which the runway disappeared; but here he halted, fearing to enter, lest he meet Tarzan returning.

The ape-man, far ahead of him, groped his way along the rocky passage, until he came to the ancient wooden door. A moment later he stood within the treasure chamber, where, ages since, long-dead hands had ranged the lofty rows of precious ingots for the rulers of that great continent which now lies submerged beneath the waters of the Atlantic.

No sound broke the stillness of the subterranean vault. There was no evidence that another had discovered the forgotten wealth since last the ape-man had visited its hiding place.

Satisfied, Tarzan turned and retraced his steps toward the summit of the kopje. Werper, from the concealment of a jutting, granite shoulder, watched him pass up from the shadows of the stairway and advance toward the edge of the hill which faced the rim of the valley where the Waziri awaited the signal of their master. Then Werper, slipping stealthily from his hiding place, dropped into the somber darkness of the entrance and disappeared.

Tarzan, halting upon the kopje's edge, raised his voice in the thunderous roar of a lion.