They faced each other like two helmeted, arrayed fencers, watching for an opening. The first speaker's voice came from behind his mask a shade higher in key and more peremptory in tone. "You heard me, Harper. Put down that wrench at once, and come away from that 'trigger.' Erickson!"
A third armored figure came around the shield which separated the uranium bomb proper from the control room in which the first two stood. "Whatcha want, Doc?"
"Harper is relieved from watch. You take over as engineer-of-the-watch. Send for the standby engineer."
"Very well." His voice and manner were phlegmatic as he accepted the situation without comment. The atomic engineer whom he had just relieved glanced from one to the other, then carefully replaced the wrench in its rack.
"Just as you say, Dr. Silard — but send for your relief, too. I shall demand an immediate hearing!" Harper swept indignantly out, his lead-sheathed boots clumping on the floor plates.
Dr. Silard waited unhappily for the ensuing twenty minutes until his own relief arrived. Perhaps he had been hasty. Maybe he was wrong in thinking that Harper had at last broken under the strain of tending the most dangerous machine in the world — an atomic power plant. But if he had made a mistake, it had to be on the safe side — slips must not happen in this business; not when a slip might result in the atomic detonation of two and a half tons of uranium.
He tried to visualize what that would mean, and failed. He had been told that uranium was potentially forty million times as explosive as TNT. The figure was meaningless that way. He thought of it, instead, as a hundred million tons of high explosive, two hundred million aircraft bombs as big as the biggest ever used. It still did not mean anything. He had once seen such a bomb dropped, when he had been serving as a temperament analyst for army aircraft pilots. The bomb had left a hole big enough to hide an apartment house. He could not imagine the explosion of a thousand such bombs, much less a hundred million of them.
Perhaps these atomic engineers could. Perhaps, with their greater mathematical ability and closer comprehension of what actually went on inside the nuclear fission chamber — the "bomb" — they had some vivid glimpse of the mind-shattering horror locked up beyond that shield. If so, no wonder they tended to blow up—
He sighed. Erickson looked up from the linear resonant accelerator on which he had been making some adjustment. "What's the trouble, Doc?"
"Nothing. I'm sorry I had to relieve Harper."