While the wall, the gate, and the palace itself, suggested in many ways almost unbelievable age, yet they were in such an excellent state of repair that it was evident that they were still inhabited by rational and intelligent creatures; while upon the south side Tarzan had seen a new tower in process of construction, where a number of blacks working under the direction of Bolgani were cutting and shaping granite blocks and putting them in place.
Tarzan had halted in a tree near the east gate to watch the life passing in and out of the palace grounds beneath the ancient portal, and as he watched, a long cavalcade of powerful Gomangani emerged from the forest and entered the enclosure. Swung in hides between two poles, this party was carrying rough- hewn blocks of granite, four men to a block. Two or three Bolgani accompanied the long line of carriers, which was preceded and followed by a detachment of black warriors, armed with battle-axes and spears. The demeanor and attitude of the black porters, as well as of the Bolgani, suggested to the ape-man nothing more nor less than a caravan of donkeys, plodding their stupid way at the behest of their drivers. If one lagged he was prodded with the point of a spear or struck with its haft. There was no greater brutality shown than in the ordinary handling of beasts of burden the world around, nor in the demeanor of the blacks was there any more indication of objection or revolt than you see depicted upon the faces of a long line of burden-bearing mules; to all intents and purposes they were dumb, driven cattle. Slowly they filed through the gate way and disappeared from sight.
A few moments later another party came out of the forest and passed into the palace grounds. This consisted of fully fifty armed Bolgani and twice as many black warriors with spears and axes. Entirely surrounded by these armed creatures were four brawny porters, carrying a small litter, upon which was fastened an ornate chest about two feet wide by four feet long, with a depth of approximately two feet. The chest itself was of some dark, weather- worn wood, and was reinforced by bands and corners of what appeared to be virgin gold in which were set many diamonds. What the chest contained Tarzan could not, of course, conceive, but that it was considered of great value was evidenced by the precautions for safety with which it had been surrounded. The chest was borne directly into the huge, ivy-covered tower at the northeast corner of the palace, the entrance to which, Tarzan now first observed, was secured by doors as large and heavy as the east gate itself.
At the first opportunity that he could seize to accomplish it undiscovered, Tarzan swung across the jungle trail and continued through the trees to that one in which he had left the body of the Bolgani. Throwing this across his shoulder he returned to a point close above the trail near the east gate, and seizing upon a moment when there was a lull in the traffic he hurled the body as close to the portal as possible.
"Now," thought the ape-man, "let them guess who slew their fellow if they can."
Making his way toward the southeast, Tarzan approached the mountains which lie back of the Valley of the Palace of Diamonds. He had often to make detours to avoid native villages and to keep out of sight of the numerous parties of Bolgani that seemed to be moving in all directions through the forest. Late in the afternoon he came out of the hills into full view of the mountains beyond—rough, granite hills they were, whose precipitous peaks arose far above the timber line. Directly before him a well-marked trail led into a canyon, which he could see wound far upward toward the summit. This, then, would be as good a place to commence his investigations as another. And so, seeing that the coast was clear, the ape-man descended from the trees, and taking advantage of the underbrush bordering the trail, made his way silently, yet swiftly, into the hills. For the most part he was compelled to worm his way through thickets, for the trail was in constant use by Gomangani and Bolgani, parties passing up it empty-handed and, returning, bearing blocks of granite. As he advanced more deeply into the hills the heavy underbrush gave way to a lighter growth of scrub, through which he could pass with far greater ease though with considerable more risk of discovery. However, the instinct of the beast that dominated Tarzan's jungle craft permitted him to find cover where another would have been in full view of every enemy. Half way up the mountain the trail passed through a narrow gorge, not more than twenty feet wide and eroded from solid granite cliffs. Here there was no concealment whatsoever, and the ape-man realized that to enter it would mean almost immediate discovery. Glancing about, he saw that by making a slight detour he could reach the summit of the gorge, where, amid tumbled, granite boulders and stunted trees and shrubs, he knew that he could find sufficient concealment, and perhaps a plainer view of the trail beyond.
Nor was he mistaken, for, when he had reached a vantage point far above the trail, he saw ahead an open pocket in the mountain, the cliffs surrounding which were honeycombed with numerous openings, which, it seemed to Tarzan, could be naught else than the mouths of tunnels. Rough wooden ladders reached to some of them, closer to the base of the cliffs, while from others knotted ropes dangled to the ground below. Out of these tunnels emerged men carrying little sacks of earth, which they dumped in a common pile beside a rivulet which ran through the gorge. Here other blacks, supervised by Bolgani, were engaged in washing the dirt, but what they hoped to find or what they did find, Tarzan could not guess.
Along one side of the rocky basin many other blacks were engaged in quarrying the granite from the cliffs, which had been cut away through similar operations into a series of terraces running from the floor of the basin to the summit of the cliff. Here naked blacks toiled with primitive tools under the supervision of savage Bolgani. The activities of the quarrymen were obvious enough, but what the others were bringing from the mouths of the tunnels Tarzan could not be positive, though the natural assumption was that it was gold. Where, then, did they obtain their diamonds? Certainly not from these solid granite cliffs.
A few minutes' observation convinced Tarzan that the trail he had followed from the forest ended in this little cul-de-sac, and so he sought a way upward and around it, in search of a pass across the range.
The balance of that day and nearly all the next he devoted to his efforts in this direction, only in the end to be forced to admit that there was no egress from the valley upon this side. To points far above the timber line he made his way, but there, always, he came face to face with sheer, perpendicular cliffs of granite towering high above him, upon the face of which not even the ape-man could find foothold. Along the southern and eastern sides of the basin he carried his investigation, but with similar disappointing results, and then at last he turned his steps back toward the forest with the intention of seeking a way out through the valley of Opar with La, after darkness had fallen.
The sun had just risen when Tarzan arrived at the native village in which he had left La, and no sooner did his eyes rest upon it than he became apprehensive that something was amiss, for, not only was the gate wide open but there was no sign of life within the palisade, nor was there any movement of the swinging huts that would indicate that they were occupied. Always wary of ambush, Tarzan reconnoitered carefully before descending into the village. To his trained observation it became evident that the village had been deserted for at least twenty-four hours. Running to the hut in which La had been hidden he hastily ascended the rope and examined the interior—it was vacant, nor was there any sign of the High Priestess. Descending to the ground, the ape-man started to make a thorough investigation of the village in search of news to the fate of its inhabitants and of La. He had examined the interiors of several huts when his keen eyes noted a slight movement of one of the swinging, cage-like habitations some distance from him. Quickly he crossed the intervening space, and as he approached the hut he saw that no rope trailed from its doorway. Halting beneath, Tarzan raised his face to the aperture, through which nothing but the roof of the hut was visible.