The Commander spoke to him slowly, with desperate emphasis; reaching into a pocket of her suit, she brought out another package of powdered metal which Vulc promptly stuffed into his mouth. "He understands," she said at last. "But I'll leave one of you here with him, to be certain he does." For a while they rested, lying prone, helmets thrown back, luxuriating in the comparative coolness and the draughts of pure air. All were thirsty, their throats parched and aching. But the nightmare was over. Presently the Commander rose to her feet and gave the order to march. She was almost her usual self again, detached, impersonal. But she was white to the lips and her eyes were electric as she said: "Luhor will pay for this!" She barely breathed it, but Mark heard her. And he knew what she meant. It was Luhor who had prepared the units of oxygen for the suits. VII Under the dim illumination maintained even as far as these outlying caves, the group went grimly on. Their passage through the tortuous corridors was dotted by discarded vacuum suits. But no echoes drifted back to them from the activity of the Base. Twice they lost their way, ending up against blank rock walls and retracing their steps. But at last the inter-connecting tunnel chain became familiar to the Commander. "She blames Luhor for the oxygen business!" Mark murmured to Carston walking beside him. "Should!" Carston exclaimed laconically, grimly. "Aladdian warned us against Luhor, remember? There'll be hell to pay when we get back! Any monkey-wrench thrown into the machinery of their plans, helps the Earth. I hope...." He broke off, staring moodily ahead. "She's far more human than you think," Mark Denning said softly. "Yes, I noticed that today." Carston's voice sounded glad. "It's only the Spartan training she learned while cruising the spacelanes with her piratical father that keeps her up--that, and the old man's insane will, driving her on through a sense of loyalty to him." They were so near to the Base now that Mark expected momentarily to hear the clang of metal in the factories, the voices of workmen. His heart quickened at the thought of seeing Aladdian, and he forgot his weariness in embroidering upon that thought. But the ominous stillness remained unbroken. They entered the final corridor leading to the vast central chamber. The Commander ran forward, with the anxious men close behind her. They entered the grotto. The subterranean Base extended into the distance before their startled, unbelieving eyes. "What--" Cynthia began bewilderedly. It was a dead city, soundless and inert. Under the distant cavern roof it had the air of a ghost town drained of all life. Mark's heart leaped into his mouth. "Aladdian!" he cried involuntarily, and his hands clenched in an agony of anxiety of helpless rage. Commander Cynthia was already running toward the palace, a deathly fear mirrored in her eyes.