In another second the flood of ape-men had burst in all its fury over him. Crashing, thundering shots were dinning in his ears, animal death screams and the Valkyrie battle cries of the girls filled the temple. He could not tell how many of the apes were fighting him. As a cave-man's club whizzed past his head, he drove his knife once, and yanked it dripping from hairy, yielding flesh to plunge it again. A sudden side-step carried him away from another assailant. He dropped the knife to snatch the gigantic club of one of the creatures he had killed. Quicker in every movement than the ape-men, he laid on, right and left, with such power that blood spurted in a dozen places, and heads were split open on every side. And because of his speed, the frantic, clumsy blows and knife thrusts which were directed at him proved harmless. A terrific drive which smashed a snarling face into pulp, left Kirby free for a second, and he emerged from the first round of battle ready to cut in and help the girls. But then he saw that he had gotten separated from the main body. "Naida!" he called. "Naida!" A series of shots answered him, and as several apes fell, a gap was opened through which he saw her conducting a well ordered retreat of all the girls toward the dark corridors surrounding the temple. Again Kirby fell to with his club, swinging, hacking, fighting with his whole strength to catch up. He made headway, and hope began to come again. The ape-men would not kill, or even harm, the girls. What they wanted was to carry them off. If he and Naida together could get their party rounded up in the corridors, the chances were good. "Naida!" he shouted again. "Coming!" Battering down an ape in front of him, he jumped up on the corpse, and saw that already the vanguard of girls had reached the first sheltering corridor. Naida had been cut off from the others by eight or ten apes. But even so her fire made her mistress of the situation, and she seemed all right. It was just as Kirby started to jump down from the corpse that he saw something which put another complexion on the matter, and left him frozen where he was. * * * * * Behind Naida, directly in the path in which her slavering aggressors were slowly forcing her, a huge stone slab in the temple floor had begun to tilt up as if it were a trapdoor raised by an invisible hand. Within the yawning opening, Kirby caught a glimpse of stone steps winding down into blackness. In a flash he saw that it was Naida, and her alone, that the ape-men were after. The Duca's determination was to capture her, and it was the presence of this trapdoor, making capture possible, which had brought on the second charge of the apes.