"This is the south face of the pile," Darcy said. "Most of the instruments are located here. The Klysten converters are mounted in that room over there." He indicated a door on their left. "I'd like to see those," Roger said. "I hear that these are pretty large compared with what we had at the moon labs." "They're big enough all right," Darcy said. "Each one is four stories high. We had a deuce of a time evacuating them." As Darcy said this, they stepped into a long high room. To their right stood six immense transparent tubes. Each tube contained a grid of thick steel bars which was mounted so that it completely surrounded a coil of heavy copper bar in the center of the tube. The steel bars had been treated so that a magnetic field would build up rapidly when they were exposed to hard radiations. The radiation beams were passed into the grid in pulses, thus causing the magnetic field to build up and collapse rapidly producing current in the coils by induction. The tubes were generators with no moving parts except electrons and protons. The system used about seventy-five per cent of the energy produced by the pile. The residual radiation was released as greenish yellow light. "Why are they transparent?" Roger asked. "I should think that metals would be stronger and easier to manage." "The transparency helps us to maintain a more accurate control," Darcy replied. "When the light shifts toward the blue, we know that more energy is being released as radiation, and can shut down the tube before it gets a chance to heat up too much." "Good idea," said Roger. "Control was our worst trouble at the moon labs." "We'll use this until we find something better," said Darcy as they left the pile area. * * * * * Unknown to Roger Lorin, events which would shape the course of the next few weeks, and would ultimately change his whole life were taking place far to the south. A third party had entered the political stage of the Western Hemisphere. The League of Islam had finally decided to do something about an incident which it had never forgiven. Over thirty years earlier, the Union had sent marines into the Suez Canal area to stop alleged assaults against American citizens. In a sense, the North American Union had indicated that it thought of the League of Islam as nothing more than a backward group, which could be pacified whenever trouble arose within its borders. The insult had never been forgotten by the fanatically nationalistic Moslems. Only the greater military might of the North American power had prevented a war at that time. Now, the League had decided that the time was ripe to gain immunity from such insults forever by some shrewd political maneuvering.