He held her back. "No, Martha, it's not that. I'm just out, dead tired. Since I reached Earth on this mission, I've had it--and only a few hours sleep in my car, last night." She took his wrist. "Then you're going to sleep right now. I'll keep watch. This way--I have to put the light out when we leave the kitchen--" Wales, following her through the dark house, felt that he was three parts asleep by the time he reached the bedroom to which she led him. His head still ached, and the headache and the exhaustion came up over him like a drowning wave. When he woke, afternoon sunlight was slanting into the dusty bedroom. He turned, and discovered that Martha sat in a chair beside the bed, her hands folded, looking at him. She said, "I wasn't sleepy. And it's been so long since I've had anyone--" She stopped, faintly embarrassed. Wales sat up, and reached and kissed her. She clung to him, for a moment. Then she drew back. "Just propinquity," she said. "You would never even look at me, in the old days." Wales grinned. "But now you're the last girl in town." Martha's face changed and she suddenly said, with a little rush of words, "Oh, Jay, do you sometimes get the feeling that it just _can't_ happen, no matter what Lee and all the other scientists say, no matter what their instruments say, that everything we've known all our lives just can't end in flame and shock from the sky--?" He nodded soberly. "I've had that feeling. We've all had it, had to fight against it. It's that feeling, in the ignorant, that'll keep them here on Earth until it's too late--unless we convince them in time." "What'll it really be like for us, on Mars?" she asked him. "I don't mean all the cheery government talks about the splendid new life we'll all have there. I mean, _really_." "Hard," he said. "It's going to be a hard life, for us all. The mineral resources there are limitless. Out of them, with our new sciences of synthesis, we can make air, water, food. But only certain areas are really habitable. Our new cities out there are already badly crowded--and more millions still pouring in." He still held her hand, as he said, "But we'll make out. And Earth won't be completely destroyed, remember. Someday years from now--we'll be coming back." "But it won't be the same, it'll never be the same," she whispered. He had no answer for that. Packaged food made them a meal, in the kitchen. It was nearly sunset, by the time they finished. Martha asked him then, with desperate eagerness, "We're going to try to find Lee now?" Wales said, "I've been thinking. We'll get nowhere by just searching blindly. Fairlie's agents did that, and found no trace of Lee at all. I think there's only one way to find him." "What?"