I had to break in on that. Jim nudged me, but Shadrak smiled. "Small wonder you're surprised," he commented. "On Earth you have a legend, of the lost Atlantis. There was a general submerging of continents. Millions perished. And we were so moved on Mars that we sent our space ships. It was one of our few real invasions. Till we visited Gregor, we hadn't returned. But that time we removed ten thousand, products of an advanced civilization. "We moved those ten thousand to Spor." Jim whistled. "Even that long ago you traveled ahead of light. I mean, with greater speed." Shadrak nodded. "You two are Earthmen we trust. We keep many secrets because it is best. But in this case--" he paused, "I want you, Jerry Kos and Jim Drake, to journey to Spor." "But it would take years," I put in. "Maybe longer." "Twenty two days and six hours, with the new ship just delivered," Shadrak corrected. "It has a capacity of one thousand. If you return with a full load, we shall send more ships to Spor." Jim looked bewildered. "Maybe it's too much," he said, "but such a speed is incredible." "There is no limit to speed," Shadrak told us. "The problem is of acceleration, and deceleration. You have that problem in handling the Pelios, which rides energy beams at the speed of light. Frequencies, whether of sound or light, as instances, are constant. Therefore we employ this fact in accelerating. We superimpose frequencies against frequencies, repelling power, one from the other. The result is a constant, increasing ratio. In effect, Jim--and you, Jerry--will grasp it much easier in this manner. If you had a machine throwing a jet of water, and it touched an opposing jet of water, your propulsion would build up till the limits of the energy from the opposing jets were reached. Suppose those jets continued to reach out. As light frequencies, till you built up your maximum. In a vacuum your speed would continue at that maximum velocity till you chose to decelerate. Now deceleration is effected by the same principle. We do it by hitching to our sun and reaching the maximum in building up speed. In like manner, another sun can be used to decelerate, by reversing the process. "But enough of that," Shadrak resumed. "Your ship will be robot controlled. Our own master navigator will get telescreened charts of your course. Your job will begin when you land, I fear. The planet of Spor enters the Noir within eighteen months, and a sudden reaction in that hundred thousand light year wide mass could reduce the engulfing to eighteen weeks." "What does this Noir mean, swallowing up Spor?" I fired that shot. And it was Jim who answered. "Noir's the light absorbing element nobody has lived to analyze. We know it absorbs all organic life as it does light, electricity, even sound. It's the black scourge of space." "And we're going to play around it, eh? To bring back the descendants of the lost Atlantis. And where do they go, providing we take 'em off?"