Tetzcatl had stepped forward, lifting his torch and peering into the gloom. Only a step or two beyond him, the floor of the cave was cut off, sharply, by one of the breaks or "faults" common to all rock formations, the token of some old-time upheaval or depression. The rugged level began again a few yards farther on, but there was no bridge across the yawning chasm which separated the corresponding edges. Three or four heavy planks which lay near indicated a possible means of crossing, if need should be, but no hand was laid upon them now. The dismal-looking companions were all leaning forward in listening attitudes, intent upon a roaring, booming sound that came up from the chasm. "They are calling," said Tetzcatl. "But we have none to give them. Well did I say that I must go." "It is too loud!" exclaimed the watcher, who had followed him most closely. "They have called my name!" Tetzcatl turned quickly, but he addressed yet another of the old men by a long, many-syllabled, vibrating invocation, and added to it, in Spanish,-- "Wilt thou go down to the gods, or shall he take thy place?" "He is gone!" was the quick but entirely unexcited rejoinder. Tetzcatl whirled again toward the gulf, but the rock-floor at his left was vacant. The withered old devotee had not hesitated for a moment, but had plunged down headlong. During a number of slow seconds no word was uttered, and all the while the booming roar from below diminished in volume until it nearly died away. "The gods are satisfied," said Tetzcatl. So seemed to think and say his associates, and they turned away to walk slowly toward the altar, as if nothing noteworthy or unusual had occurred. It is not always easy to give satisfactory explanations of the sounds which are to be heard, more or less intermittently, among the chasms and recesses of great caves. The flow of subterranean waters, the rush of air-currents, the effects of echoes, and many other agencies have been taken into account. As for Tetzcatl and his friends, they had but formed and expressed an idea which was anciently universal. This voice from the deep was but one of the oracles which have been so reverenced by the primitive heathenisms of many nations. As for the treasure, from whatever placers it had been gathered, its presence in such a place required no explanation. The Aztec kings had but exhibited commonplace prudence in choosing for it so secure a hiding. The cave was not at all more mysterious than might be the underground vault of a great city bank or a United States Sub-Treasury. It was as safe even from burglary, if the vault-entrance was well guarded. More than a score of the grisly, blanketed shapes were now gathered at the altar. Its fire was blazing high, and shed its red, wavering radiance upon their faces, while Tetzcatl stood upon the lower of the steps and addressed them. He spoke altogether in their own tongue, and they listened without reply or comment.