IN THE TEMPLE of Brulor all was confusion and excitement. Priests and warriors filled the throne room, investigating the mysterious disappearance of two prisoners. The locks of their cages were intact, and only d’Arnot guessed the truth as he noted a slight bend in two of the bars of Tarzan’s cage.
“Once again there is hope,” he whispered to Brian.
An excited ptome ran into the throne room; and, tearing off his helmet, hurried to the foot of Brulor’s throne. “O Father of Diamonds,” he cried, “I went to the little chamber in the lake. The woman is gone!”
“Gone? Where?” demanded Brulor.
“Who knows?” replied the ptome. “All that I know is that she is not there and that scattered over the bottom of Horus are the bodies of six ptomes, their water suits stripped from three. A demon is in our midst, O Father!”
Brulor leaped to his feet, trembling with rage. “They are not demons,” he cried, “but mortal men who may die. One is that renegade, Herkuf; the other is the man called Tarzan. Whoever brings them to me, dead or alive, may name his own reward; but bring them alive if you can. Whoever profanes the temple of Brulor must die. So it is written.”
And while Brulor raged, the objects of his wrath, led by Herkuf, were far out on the bottom of Horus. Having stripped the water suits from three of the dead ptomes, they had followed Herkuf, who was bent on leading them across the lake in accordance with the plan that he and Tarzan had decided upon before their escape from the temple. Good fortune had given them possession of three extra water suits, which would fit in nicely with the plan they had in mind, a mad plan; but the only one that seemed at all likely to succeed.
As they approached deeper water, they descended into a valley of huge marine plants; and here they encountered the larger denizens of the deep; so that they were constantly compelled to fight off attacks, as monstrous, shadowy shapes glided about them. Mighty, grotesque plants waved their fronds above them in the dim light of the fading stars.
Helen was frankly terrified. She had no idea who these men were, nor where they were taking her, nor what their intentions toward her; and in addition to these, she did not see how they could escape the terrifying dangers that surrounded them, made doubly terrifying by the darkness and the strangeness of the scene. She felt that she could endure no more, and then a huge sea serpent swam from among the giant trees and rushed to attack them.
The men faced its horrible jaws with their puny tridents, while its long, sinous tail wreathed in spirals above them, like a sentient Damoclean sword that might destroy them at any moment. Its protruding eyes glaring, its forked tongue darting from its fanged jaws, the serpent suddenly wrapped its tail about Helen and swam off. Instantly Tarzan dropped the extra water suit and helmet he had been carrying and sprang up in an effort to reach them, as Herkuf stood helpless on the lake bottom below.
Just by chance, the ape-man succeeded in seizing one of Helen’s ankles; but he could not wrest her from the grip of that powerful tail. Slowly he drew himself up over the body of the girl in an effort to reach the body of the serpent. At the same time he tried to wrest her free; but the coils only tightened about her; and as the angry saurian turned and twisted, he had difficulty in holding on at all. It was only his great strength and agility that, despite his encumbering water suit, permitted him, finally, to climb to the monster’s back. Again and again he drove his knife into the cold body, while Helen marvelled at the courage and strength of her unknown paladin.
Painfully, but not seriously wounded, the saurian dropped the girl and turned upon the man-thing that dared thus to question its supremacy. Bleeding, hurt, infuriated, a creature of demoniacal fury, its one thought now was to destroy this rash thing that threatened its right to self-preservation. Fending off the jaws with his sharp knife that inflicted hurts which caused the serpent to recoil, Tarzan climbed steadily toward the great throat. Numa, the lion; Sheeta, the leopard; Wappi, the antelope; and man he had killed by severing the jugular. Why not this creature, too, in which blood flowed?
At last he reached his goal; and here, beneath the great throat, he found the tenderest skin his blade had yet pierced; and with a single stroke he severed the vein he had been seeking. There was a gush of blood, the creature writhed convulsively for a few moments; and then, as Tarzan slipped from its back, it turned belly up and floated away; while the ape-man sank gently toward the floor of the lake, where Helen stood, wide-eyed and wondering, looking up at him.
Dawn was breaking; and the increasing light made it possible for them to see to greater distances than before, and as Tarzan looked about for Herkuf, he saw him approaching, bringing along the water suit and helmet that Tarzan had discarded.
From this point on, the lake bottom rose steeply, taxing Helen’s energies to such an extent that Tarzan had to help her for the remainder of the way to shore. Herkuf was not much better off than Helen, but he managed to stagger out of the water to fall exhausted on the bank. Only Tarzan seemed fresh and untired.
They lost no time in removing the uncomfortable helmets, and when Helen saw Tarzan’s face she cried out in astonishment. “Tarzan!” she exclaimed. “But I might have known that it was you, for who else could have done for me what you have?”
“Paul,” he said, with a smile.
“You’re sweet,” she said. “Oh, what a relief to feel safe once more. How wonderful to be alive after all that we have gone through, after that terrible chamber where they would have drowned me. I can’t believe yet that I have escaped.”
Close to shore, Herkuf had speared a fish; and now he led them to a cave he knew of; and while Helen and Tarzan lay on the ground, he built a fire and broiled his catch.
“What are your plans?” Helen asked Tarzan.
“Herkuf knows where a boat is hidden on this side of the lake. We thought it safer to come here rather than to attempt to steal one from the quay at Ashair, knowing that after our escape was discovered there would be sentries everywhere. Tonight, we shall row across the lake; and Herkuf and I will go down in water suits and try to get past the ptomes again and bring out d’Arnot, Brian, and Lavac. That is why we took the three suits from the ptomes we killed. We were going to try to steal them from the ptomes’ room. Now we won’t have to go through that room, as we did before to steal suits, as Herkuf says there is a way around it.”
“After we have eaten and rested,” said Herkuf, “I’ll go and see if the boat is still where I hid it. That was many years ago; but it was well hidden, and it is seldom that anyone comes to this part of the valley. I sank it in a tiny inlet beneath bushes that overhung the water.”
“It has probably rotted away by this time,” suggested Helen.
“No, I think not,” replied Herkuf. “It would only rot if exposed to the air.”
As they ate the broiled fish, they discussed their plans and recalled the adventures through which they had passed; and Helen asked Herkuf how it had been possible to construct the temple at the bottom of the lake. “That seems to me,” she said, “an engineering feat far beyond the capabilities of the Asharians, for nothing else that they have accomplished, as far as I have seen, suggests more than a primitive knowledge of engineering. With the exception of these diving helmets, I have seen nothing that indicates great inventive genius, either.”
“It was the invention of the diving helmet, coupled with a natural phenomenon, that made it possible to build the temple,” explained Herkuf. “We are a very ancient race. We have occupied the valley of Tuen-Baka for perhaps three thousand years. Our origin is legendary, but it is believed that our early ancestors came down from the north, bringing with them a well developed civilization and considerable engineering knowledge. There were two factions or tribes. One settled at what is now Thobos, the other at Ashair. It was an Asharian who invented the diving helmet. He was always puttering around with metals and chemicals, trying to make gold from common substances; and during his experiments, he accidentally discovered a combination of chemicals that, when water was poured on them, generated air that could be breathed; but he had a sad end just as he was about to transmute a black powder he had compounded into gold. All that was necessary, he believed, was to apply great pressure suddenly; so he placed a little of it on a piece of lava and struck it with a hammer. There was a terrific noise and much smoke; and the roof blew off the inventor’s house, and he went with it. One of his assistants, who miraculously escaped death, saw it all. But, though he did not succeed in making gold, he left behind him a great invention in the form of the diving helmet, which was thoroughly perfected and in common use, though more for sport than for any practical purpose.”
“But what had that to do with the building of the temple?” asked Helen.
“I am coming to that. Off shore from Ashair, at the point above where the temple now stands, the water was always in constant turmoil, a jet of it often flying into the air fifty or a hundred feet with a great hissing sound. The origin of this phenomenon was a mystery which the Asharians would have liked to solve; so, one day, a venturesome youth donned a water suit and helmet and set forth on the bottom of the lake to investigate. He was gone about half an hour, when watchers on the shore saw him shoot up, above the surface of the water at the spot where the phenomenon occurred. By a miracle, he was not killed; and when he finally came back to shore, he reported that a great geyser of air was shooting up from a hole in the bottom of the lake.
“It was many years later that some one conceived the idea of building a temple around the air geyser to house the priesthood and holy of holies. Thousands of slaves were captured and set to cutting the lava blocks that were to form the temple walls. Innumerable water suits and helmets were made. The most difficult part of the work was the capping of the air geyser, but this was finally accomplished; then the building of the temple commenced. It took a thousand years and cost twice that many lives. When it was completed and tightly sealed, it was, of course, entirely filled with water; but when the valve that had been installed in the geyser cap was opened, the water was forced out of the temple through a one-way valve. Today, the geyser furnishes pure air for the temple and actuates the doors of the air chambers.”
“How wonderful!” commented Helen. “But where does this air supply come from?”
“It is, of course, mere conjecture,” replied Herkuf; “but the theory is that during a great eruption, when Tuen-Baka was an active volcano, the entire top of the mountain was blown off and that when a great portion of it fell back into the crater it imprisoned a vast quantity of air, under great pressure, in a subterranean reservoir.”
“And when that supply is exhausted?” inquired the girl.
Herkuf shrugged. “Horus will reclaim the temple. But there is yet a second theory. It is possible that there exists beneath the temple an immense deposit of the very chemicals that we use in our helmets, and that the trickling of water from the lake into this deposit is constantly generating fresh air.”
“What a world of thought and labor and lives must have gone into the building of that structure!” exclaimed Helen, “and to what purpose? Why do men so waste their energies?”
“Does your race build no temples to its gods?” asked Herkuf.