If you let a man learn, and study, and work—and clamp a lid on so that nothing he takes into his mind can be let out—one way or another he'll blow a safety valve! BY ERNEST M. KENYON Illustrated by Freas Suddenly Collins snapped the pencil between his fingers and hurled the pieces across the lab, where they clattered, rolled from the bench to the floor, and were still. For a moment he sat leaning against the desk, his hands trembling. He wasn't sure just when the last straw had been added, but h