"That seems not actually the creation of new matter, but we have another effect which is this. A tiny rod of steel--a needle the length of my finger--may hang motionless balanced upon a pivot. It is a material body which we would call three or four inches long, by one-hundredth of an inch thick and broad. We set it swinging--vibrating--whirling in a circle with the pivoted end as the center. With a swift enough movement that circle is impenetrable. In effect, out of that needle, we have created a steel disc, one-hundredth of an inch thick, with a diameter of say eight inches. An area of material substance hundreds of times greater than the needle--yet the mass is not increased." "Quite so," Thone agreed. "Our thought-waves have a mass infinitesimal. But like your steel disc, they can momentarily become very tangible to our Ego-senses. A tangibility very different, yet comparable to our bodies themselves. Less mass, yet more power. Under some circumstances they may alter an inert substance, as I have made transparent to our vision that segment of the globe over there, beyond which we see the city. Or they can enmesh a material organism--your body, for instance--I had meant to demonstrate that." He moved away from Will, stood quiet; and about Will he flung his wave of thoughts, so that Will was drawn irresistibly to him--as Bee and I were even then enmeshed by Brutar's thought-substance. Thone laughed. The net of his thoughts dissolved. "You see? It is a very tangible substance. Yet elusive as well. We understand partially its uses. Yet only partially. Its nature is varied from a tenuosity impalpable, to the physical substances which form the entities of our universe. Like that thing you described as your Light-waves, our Thought-substance can traverse Space with tremendous velocity. Not a finite, measurable velocity, as with your Light, but with a speed infinitely rapid. "A thought may travel to infinity and back in an instant. That--understand me--relates only to its most tenuous form, impalpable to our physical senses--perceived only dimly and only occasionally by a mind other than that from which it originates. In more solid forms its velocity is slower. But it is all under control of our Ego-willpower. Do I confuse you?" "A little," Will admitted. "I am trying to hold a clear conception of it all. I understand you have a void of Space. Must it not be filled with something besides these Thought-entities? Some all-pervading, impalpable fluid?" * * * * * "We do not know," said Thone frankly. "There are emanations from our immobile organisms. Thus we breathe and eat--the substance of our bodies is renewed--but of that I shall tell you more at another time. You were saying--"