Later that afternoon Barry sent for Andrew, who had asked to be present when Mark began to talk. They sat on either side of the bed and watched the boy stir, rousing from the deep sleep that had quieted him so thoroughly that he had appeared dead.

Mark opened his eyes and saw Barry. "Don't put me in the hospital," he said faintly, and closed his eyes again. Presently he opened his eyes and looked about the room, then back to Barry. "I'm in the hospital, aren't I? Is anything wrong with me?"

"Not a thing," Barry said. "You passed out from exhaustion and hunger, that's all."

"I would like to go to my own room then," Mark said, and tried to rise.

Barry gently restrained him. "Mark, don't be afraid of me, please. I promise you I won't hurt you now or ever. I promise that." For a moment the boy resisted the pressure of his hands, then he relaxed. "Thank you, Mark," Barry said. "Do you feel like talking yet?"

Mark nodded. "I'm thirsty," he said. He drank deeply. He began to describe his trip north. He told it completely, even how he had frightened Gary and his brothers and routed the expedition to Philadelphia. He was aware that Andrew tightened his lips at that part of the story, but he kept his eyes on Barry and told them everything.

"And then you came back," Barry said. "How?"

" 'Through the woods. I made a raft to cross the river." Barry nodded. He wanted to weep, and didn't know why. He patted Mark's arm. "Rest now," he said. "We'll get word to them to stay in Washington until we dig up some radiation detectors."

"Impossible!" Andrew said angrily outside the door. "Gary was exactly right in pressing on to Philadelphia. That boy destroyed a year's training in one night."

"I'm going too," Barry had said, and he was with Mark now in Washington. Two of the younger doctors were also with them. The young expedition members were frightened and disorganized; the work had come to a stop, and they had been waiting in the main building for someone to come give them new instructions.

"When did they start out again?" Barry demanded.

'The day after they got back here," one of the young boys said.

"Forty boys!" Barry muttered. "And six fools." He turned to Mark. "Would we accomplish anything by starting after them this afternoon?"

Mark shrugged. "I could alone. Do you want me to go after them?"

"No, not by yourself. Anthony and I will go, and Alistair will stay here and see that things get moving again."

Mark looked at the two doctors doubtfully. Anthony was pale, and Barry looked uncomfortable.

"They've had about ten days," Mark said. "They should be in the city by now, if they didn't get lost. I don't think it would make much difference if we leave now or wait until morning."

"Morning, then," Barry said shortly. "You could use another