y 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 o