His mind felt as if it were racing in neutral, getting nowhere. Within that sphere was the total energy that had been poured out by five gigantic beams, turned on full, for almost a minute's time. Compressed energy! Energy enough to blast these mountains down to the primal rock were it released instantly. Energy trapped and held by virtue of some peculiarity of that little borderline between Force Fields 348 and 349. Russ walked across the room to a small electric truck with rubber caterpillar treads, driven by a bank of portable accumulators. Skillfully the scientist maneuvered it over to the other side of the room, picked up a steel bar four inches in diameter and five feet long. Holding it by the handler's magnetic crane, he fixed it firmly in the armlike jaws on the front of the machine, then moved the machine into a position straddling the sphere of force. With smashing momentum the iron jaws thrust downward, driving the steel bar into the sphere. There was a groaning crash as the handler came to a halt, shuddering, with only eight inches of the bar buried in the sphere. The stench of hot insulation filled the room while the electric motor throbbed, the rubber treads creaked, the machine groaned and strained, but the bar would go no farther. Russ shut off the machine and stood back. "That gives you an idea," he said grimly. "The trick now," Greg said, "is to break down the field." Without a word, Russ reached for the power controls. A sudden roar of thunderous fury and the beams leaped at the sphere ... but this time the sphere did not materialize again. Again the wrench shuddered through the laboratory, a wrench that seemed to distort space and time. Then, as abruptly as it had come, it was gone. But when it ended, something gigantic and incomprehensibly powerful seemed to rush soundlessly by ... something that was felt and sensed. It was like a great noiseless, breathless wind in the dead of night that rushed by them and through them, all about them in space and died slowly away. But the vanished steel did not reappear with the disappearance of the sphere and the draining away of power. Almost grotesquely now, the handler stood poised above the place where the sphere had been and in its jaws it held the bar. But the end of the bar, the eight inches that had been within the sphere, was gone. It had been sliced off so sharply that it left a highly reflective concave mirror on the severed surface. "Where is it?" demanded Manning. "In that higher dimension?" Russ shook his head. "You noticed that rushing sensation? That may have been the energy of matter rushing into some other space. It may be the key to the energy of matter!" Gregory Manning stared at the bar. "I'm staying with you, Russ. I'm seeing this thing through." "I knew you would," said Russ.