"Yes; and that accounts for the impossible location of the planet, too. They probably materialized it out there, just for the exercise. There, they're coming back. Feel 'em?"

Vivid thoughts, for the most part incomprehensible, flashed from the headsets into their minds; and instantly the surroundings of their projections changed. With the speed of thought a building materialized upon that barren ground, and they found themselves looking into a brilliantly lighted and spacious hall. Walls of alabaster, giving forth a living, almost a fluid light. Tapestries, whose fantastically intricate designs changed from moment to moment into ever new and ever more amazingly complex delineations. Gem-studded fountains, whose plumes and gorgeous sprays of dancing liquid obeyed no Earthly laws of mechanics. Chairs and benches, writhing, changing in form constantly and with no understandable rhythm. And in that hall were the intellectuals—the entities who had materialized those objects from the ultimately elemental radiant energy of intergalactic space.

Their number could not even be guessed. Sometimes only one was visible, sometimes it seemed that the great hall was crowded with them—ever-changing shapes varying in texture from the tenuousness of a wraith to a density greater than that of any Earthly metal.

So bewilderingly rapid were the changes in form that no one appearance could be intelligently grasped. Before one outlandish and unearthly shape could really be perceived it had vanished—had melted and flowed into one entirely different in form and in sense, but one equally monstrous to Terrestrial eyes. Even if grasped mentally, no one of those grotesque shapes could have been described in language, so utterly foreign were they to all human knowledge, history, and experience.

And now, the sixth-order projections in perfect synchronism, the thoughts of the Outlanders came clearly into the minds of the four watchers—thoughts cold, hard, and clear, diamondlike in polish and in definition; thoughts with the perfection of finish and detail possible only to the fleshless mentalities who for countless millions of years had done little save perfect themselves in the technique of pure and absolute thinking.

The four sat tense and strained as the awful import of those thoughts struck home; then, at another thought of horribly unmistakable meaning, Seaton snapped off his power and drove lightning fingers over his keyboard, while the two women slumped back, white-faced and trembling, into their seats.

"I thought it was funny, back there that time, that that fellow couldn't integrate in the ninety-seven dimensions necessary to dematerialize us, and I didn't know anything then." Seaton, his preparations complete, leaned back in his operator's seat at the console. "He was just kidding us—playing with us, just to see what we'd do, and as for not being able to think his way back—phooie! He can think his way through ninety-seven universes if he wants to. They're certainly extragalactic, and very probably extrauniversal, and the one that played with us could have dematerialized us instantly if he had felt like it."

"That is apparent, now," Crane conceded. "They are quite evidently patterns of sixth-order forces, and as such have a velocity of anything they want to use. They absorb force from the radiations in free space, and are capable of diverting and of utilizing those forces in any fashion they may choose. They would of course be eternal, and, so far as I can see, they would be indestructible. What are we going to do about it, Dick? What can we do about it?"

"We'll do something!" Seaton gritted. "We're not as helpless as they think we are. I've got out five courses of six-ply screen, with full interliners of zones of force. I've got everything blocked, clear down to the sixth order. If they can think their way through those screens they're better than I think they are, and if they try anything else we'll do our darnedest to block that, too—and with this Norlaminian keyboard and all the uranium we've got that'll be a mighty lot, believe me! After that last crack of theirs they'll hunt for us, of course, and I'm pretty sure they'll find us. I thought so—here they are! Materialization, huh? I told him once that if he'd stick to matter that I could understand, I'd give him a run for his money, and I wasn't kidding him, either."