“Yes. Commander—” Brady didn’t finish. One look at Desquer’s grim face was enough. “Don’t be a fool, captain. Get your rest—and the rest of you, too. You’ll need it. You know well enough we can’t rescue Ruggiero.” That, Tony thought as he relaxed, was true; but nevertheless he had a curiously unpleasant feeling at the base of his spine. Somewhere amid these caverns a white man was being horribly sacrificed, and it was not a thought conducive to sound sleep. Yet Desquer was right. The legionnaires’ only chance was to remain hidden ... Once Tony roused sleepily to find the Commander lying down and Captain Brady on guard. Brady was wandering about the cavern, staring up at the carving of the Moon and sistrum. He was a gaunt, scarecrow figure in the dim light. As Tony drifted off again to sleep he realized that the faint chanting had grown louder— That it was different now in tone—triumphant! And then Desquer was shaking Tony’s shoulder, his hand pressed over the legionnaire’s lips. The commander’s eyes were glittering brightly. “_Sh-h!_ Not a sound! Rouse the others.” Silently Tony obeyed. There was no sign of Captain Brady, he realized. On cat feet Desquer led the three into the tunnel. Hidden by the first turn, he whispered, “Brady’s gone. When I woke up—” Jimmy asked, “What happened to him? The Copts?” “Perhaps.” “But wouldn’t they have killed us, then?” Desquer passed a hand over his shaven head. “Not necessarily. They may have other plans.” He smiled, not pleasantly. “So Brady’s gone. That leaves the four of us.” There was an oddly secretive look in the cold eyes. “Come on. We’re still heading for Alu.” “What’s the use?” Tony asked. “If the Copts have discovered us—” “They may not have. Brady may have gone off to try and save Ruggiero. I doubt that, though—but we mustn’t overlook any chances. Alu is our destination. So—_allons!_” The three brothers exchanged glances. One by one their number was being cut down. First the entire garrison of the fort; then Jacklyn; now Captain Brady. Tony felt a twinge of sympathy for the weatherbeaten old soldier. Whatever had happened to the man, Brady would have gone down fighting. “He didn’t try to warn us,” Jimmy muttered. Desquer grunted. “We don’t know all the weapons of those Copts. Where they get them God knows. Every once in a while they’ll pop up with some super-scientific device far beyond their power to manufacture. It’s a mystery. Maybe we’ll find the answer in Alu.” That, to Tony, was a strange paradox. A search amid the ruins of a forgotten past for the super-science of the future. And yet—whence had come the mighty civilization of Egypt? What mystery lay behind the cryptic powers of the Copts? There could be no answer, as yet. The four men marched on, down into the depths. They were beneath the Midnight Sea now, Tony decided, since the tunnel had curved in a long loop. Not only beneath the Sahara Desert, but under a sunken sea as well.