That its few inhabitants were direct descendants of its once powerful builders seemed not unlikely in view of the rites and ceremonies of the ancient religion which they practiced, as well as by the fact that by scarcely any other hypothesis could the presence of a white-skinned people be accounted for in this remote and inaccessible African fastness.
The peculiar laws of heredity, which seemed operative in Opar as in no other portion of the world, suggested an origin differing materially from that of other men; for it is a peculiar fact that the men of Opar bear little or no resemblance to the females of their kind. The former are short, heavy set, hairy, almost ape-like in their conformation and appearance, while the women are slender, smooth skinned and often beautiful. There were certain physical and mental attributes of the men that had suggested to Tarzan the possibility that at some time in the past the colonists had, either by choice or necessity, interbred with the great apes of the district; and he also was aware that owing to the scarcity of victims for the human sacrifice which their rigid worship demanded that it was common practice among them to use for this purpose either males or females who deviated considerably from the standard time had established for each sex, with the result that through the laws of natural selection an overwhelming majority of the males would be grotesque and the females normal and beautiful.
It was with such reveries that the mind of the ape-man was occupied as he crossed the desolate valley of Opar, which lay shimmering in the bright sunlight that was relieved only by the shade of an occasional gnarled and stunted tree. Ahead of him and to his right was the small rocky hillock, upon the summit of which was located the outer entrance to the treasure vaults of Opar. But with this he was not now interested, his sole object being to fore-warn La of the approach of the invaders that she might prepare her defense.
It had been long since Tarzan had visited Opar; but upon that last occasion, when he had restored La to her loyal people and re-established her supremacy following the defeat of the forces of Cadj, the high priest, and the death of the latter beneath the fangs and talons of Jad-bal-ja, he had carried away with him for the first time a conviction of the friendliness of all of the people of Opar. He had for years known that La was secretly his friend, but her savage, grotesque retainers always heretofore had feared and hated him; and so it was now that he approached Opar as one might approach any citadel of one's friends, without stealth and without any doubt but that he would be received in friendship.
Nkima, however, was not so sure. The gloomy ruins terrified him. He scolded and pleaded, but all to no avail; and at last terror overcame his love and loyalty so that, as they were approaching the outer wall, which loomed high above them, he leaped from his master's shoulder and scampered away from the ruins that confronted him, for deep in his little heart was an abiding fear of strange and unfamiliar places, that not even his confidence in Tarzan could overcome.
Nkima's keen eyes had noted the rocky hillock which they had passed a short time before, and to the summit of this he scampered as a comparatively safe haven from which to await the return of his master from Opar.
As Tarzan approached the narrow fissure which alone gave entrance through the massive outer walls of Opar, he was conscious, as he had been years before on the occasion of his first approach to the city, of unseen eyes upon him, and at any moment he expected to hear a greeting when the watchers recognized him.
Without hesitation, however, and with no apprehensiveness, Tarzan entered the narrow cleft and descended a flight of concrete steps that led to the winding passage through the thick outer wall. The narrow court, beyond which loomed the inner wall, was silent and deserted; nor was the silence broken as he crossed it to another narrow passage which led through it; at the end of this he came to a broad avenue, upon the opposite side of which stood the crumbling ruins of the great temple of Opar.
In silence and solitude he entered the frowning portal, flanked by its rows of stately pillars, from the capitals of which grotesque birds glared down upon him as they had stared through all the countless ages since forgotten hands had carved them from the solid rock of the monoliths. On through the temple toward the inner courtyard, where he knew the activities of the city were carried on, Tarzan made his way in silence. Perhaps another man would have given notice of his coming, voicing a greeting to apprise them of his approach; but Tarzan of the Apes in many respects is less man than beast. He goes the silent way of most beasts, wasting no breath in useless mouthing. He had not sought to approach Opar stealthily, and he knew that he had not arrived unseen. Why a greeting was delayed he did not know, unless it was that, after carrying word of his coming to La, they were waiting for her instructions.
Through the main corridor Tarzan made his way, noting again the tablets of gold with their ancient and long undeciphered hieroglyphics. Through the chamber of the seven golden pillars he passed and across the golden floor of an adjoining room, and still only silence and emptiness, yet with vague suggestions of figures moving in the galleries that overlooked the apartment through which he was passing; and then at last he came to a heavy door beyond which he was sure he would find either priests or priestesses of this great temple of the Flaming God. Fearlessly he pushed it open and stepped across the threshold, and in the same instant a knotted club descended heavily upon his head, felling him senseless to the floor.