file room and turned the knob. He slipped out, and ran on his toes down the empty corridor. Quickly, without thought of the consequence, Ron opened still another door and closed it behind him. He looked at the shining brass fixtures and ultra-modern appliances, and wondered what a kitchen was doing in a government medical building. Then, when he heard a sound in the adjoining room, he reasoned that he had stumbled into someone's living quarters. He went to a brown mahogany door and pushed against it gently until he widened the crack sufficiently to make out the figure walking up and down in the other room. When the man crossed his line of vision, Ron's breath tumbled out in a gasp. It was his own body. His thirty-year-old body, with its six-foot-two frame of big bones and long muscles, its sandy, close-cropped hair, its brooding eyes and full mouth. It was Ron Carver. It was himself as he had been before. "Here's the little rascal," a voice said behind him. The crinkly-haired man took his arm roughly. "Okay, kid. Let's hear it." "Hear what?" Ron said plaintively. "I wasn't doing anything!" "Sure," the guard sneered. "He wasn't doin' a thing. Just snoopin' around, that's all." The swinging door opened. "What's going on here?" Ron Carver looked at himself; at his own face, now strange and stony; at his own eyes, now bright and disinterested; at his own mouth, now a thin line of discontent. He heard his own voice, in a dangerous inflection he had never known before. "Sorry, sir," the guard said, reddening. "Didn't know you were inside. Wouldn't have disturbed you--" "How did he get here?" "Gosh, sir, I really don't know. He says he was lookin' for Dr. Minton--" "Minton," Ron Carver's voice said. "Yes, of course. He would be looking for Minton, wouldn't he?" "Sir?" "Never mind. Bring the boy into my quarters. Then get Dr. Minton up here at once."