The passing air no longer shrieked insanely. Above its soft rushing sound he heard the girl's voice; it was clear, vibrant with happiness. Her hand closed convulsively over his; her eyes beneath their long lashes smiled unspoken words of welcome, of comradeship, and of something more. Within their room her light, which at close range seemed only a slender bar of metal with a brilliantly glowing end, had been clamped in a bracket against the wall. The illumination had seemed brilliant, now suddenly it was pale and dim. Through the bull's-eyes above, a brighter light was shining, clear and golden, like the light of the sun on a brilliant and cloudless day. And to Rawson, who felt that he had spent a lifetime in the gloomy dungeons of that inner world, that flooding brilliance was more than mere light. It was the promise of release, the very essence of hope. His eyes clung to these little round windows; then the larger glass beside him blazed forth with the bright sunlight of an open world that was unbearable to one who had lived so long in darkness. He held tightly to that slim hand that remained so confidingly within his own. "It isn't true," Rawson was telling himself frantically. "It can't be true. It must be a delusion, another dream." He gripped the girl's hand in what must have been a painful clasp. He told himself that she at least was real. Her lovely face was before him when at last he could bear to open his eyes. * * * * * About him were the others. The cylinder rested firmly upon a surface of pale-rose quartz. Inside the shell he saw the floor where he had stood, and with that he added one more fact to the few he had gotten together. There was no dent in the floor. The shell's position was reversed. What had been up was now down. Rawson knew he was standing firmly, with what seemed his normal earth weight, upon a smooth surface of rock; he knew that he was standing head down as compared with his position at the beginning of their flight--as compared, too, with the way he had stood in the mole-men's world and in his own world up above. "I've passed the center of the world." The words were ringing in his brain. And then reason shot in a quick denial. "You're as heavy as you were on earth," he told himself. "You'd have to go through and on to the other side, the opposite surface of the world, before your weight would come back like that!" "What could it mean?" he was demanding as his eyes came back from the machine and swept around over a gorgeous, glittering panorama of crystal mountains, rose and white. Fields of strange plants, vividly green; a whole world that rioted madly in a luxury of color. Before him the girl stood smiling. Every line of her quivering figure spoke eloquently of her joy in seeing this world through Rawson's eyes. * * * * *