was prepared to take even this step, if the oxygen plan failed—because it was possible that the compressed gas would run out before the pile was activated.
The Doctor, standing in a tiny gallery directly beneath the engine-room platform, called out the falling pressure readings on the oxygen manometers, while the other five men worked above him feverishly. The Physicist was stationed at a control board so makeshift that any Earth-based technician would have gasped in horror. The Engineer hung upside down beneath the generator ring, black with grease, fastening the contact brushes. And the Captain and the Cyberneticist watched the dial of the neutron counter, while the Chemist rushed back and forth like a messenger boy, delivering tools.
The oxygen hissed, and the air compressor made angry noises, rattling, because the rotor the Engineer had jury-rigged was poorly balanced. The RPM of the generator increased, and its wail went up in pitch. The lights suspended by cables from the ceiling now emitted a powerful white glare.
"Two hundred and eighteen, two hundred and two, one hundred and ninety-five," came the muffled voice of the invisible Doctor.
The Engineer crawled out from under the dynamo, wiping the grease and sweat from his unshaven face. "Ready," he panted. His hands trembled from exertion.
"I'm switching on the first one," the Physicist said.
"One hundred and seventy, one hundred and sixty-three, one hundred and sixty," the Doctor continued, raising his voice to be heard over the whine. The dynamo was now producing current for the reactor and with each second required more oxygen to maintain its RPM.
"Full load!" groaned the Engineer, watching the dials.
"All right!" said the Physicist in a strangled voice, and, crouching as if in anticipation of a blow, he pressed the black handles with both hands.
The Captain was gripping his arm harder, without realizing it. They stared as all the pointers rapidly rose toward the vertical: the one indicating neutron flux, the one indicating isotope contamination, and the thermopile. The dynamo howled, sparks flew from under the rings, but inside the pile, behind the thick walls of steel, there was silence. Those indicators did not move. Suddenly the Physicist saw them blur. He squeezed his eyes shut, and when he opened them saw that they were in working position.
"We did it!" he shouted, and began to sob, still clutching both handles. Suddenly he felt very weak. He had been expecting an explosion the whole time.
"The indicators must have jammed," the Captain said calmly, apparently unaware of the Physicist's emotion. But he spoke with difficulty—his jaws were still tightly clenched.
"Ninety, eighty-one, seventy-two…" the Doctor intoned.
"Now!" cried the Engineer, and with a gloved hand pulled the main switch. The generator groaned, slowed. The Engineer rushed to the air compressor and closed both intake valves.
"Forty-six, forty-six, forty-six," the Doctor repeated.
The turbine was no longer taking oxygen from the tank. The lights dimmed; it grew darker in the room.
"Forty-six, forty-six…" the Doctor intoned from under the platform. Suddenly the lights blazed. The dynamo now barely turned, but there was current; all the dials showed current.
"Forty-six … forty six…" repeated the Doctor, who, in the steel well of the gallery, knew nothing of what was going on. The Physicist sat down on the floor and covered his face with his hands. There was now almost total silence. The generator rumbled slightly as it ground slowly to a halt; that was all.
"The leakage?" asked the Captain.
"Normal," replied the Cyberneticist. "The robot must have managed to seal the pile before it shorted." He spoke dryly, but everyone knew how proud he was of the robot. He clasped his hands to keep them from trembling.
"Forty-six…" intoned the Doctor.
"Enough!" the Captain shouted into the steel well. "It's no longer necessary. The pile is producing current!"
After a moment the