It failed, and in the instant of its going down actuated a zone of force--a complete stasis in the ether itself, through which no possible manifestation, either of matter or of energy in any form, could in any circumstances pass. Or could it? Radnor clenched his teeth and waited. Whether or not there was a sub-ether--something lying within and between the discrete particles which actually composed the ether--was a matter of theoretical controversy and of some academically scientific interest. But, postulating the existence of such a medium and even that of vibrations of such infinitely short period that they could be propagated therein, would it be even theoretically possible to heterodyne upon them waves of ordinary frequencies? And could those amorphous monstrosities be so highly advanced that they had reduced to practical application something that was as yet known to humanity only in the vaguest, most tenuous of hypotheses? Minute after minute passed, however, during which the Valeronian remained alive within an intact ship which, he knew, was hurtling upward and away from Chlora at the absolute velocity of her inertia, unaffected by gravitation, and he began to smile in relief. Whatever might lie below the level of the ether, either of vibration or of substance, it was becoming evident that the Chlorans could no more handle it than could he. For half an hour Radnor allowed his craft to drift within her impenetrable shield. Then, knowing that he was well beyond atmosphere, he made sure that his screens were full out and released his zone. Instantly his screens sprang into a dazzling, coruscant white under the combined attack of two space ships which had been following him. This time, however, the Chloran beams were stopped by the third screen. Either the enemy had not had time to measure accurately his power, or they had not considered such measurement worth while. They were now to pay dearly for not having gauged his strength. Radnor's beam, again a stabbing stiletto of pure energy, lashed out against the nearer vessel; and that luckless ship mounted no such generators as powered her parent fortress. That raging spear, driven as it was by all the power that Radnor had been able to pack into his cruiser, tore through screens and metal alike as though they had been so much paper; and in mere seconds what had once been a mighty space ship was merely a cloud of drifting, expanding vapor. The furious shaft was then directed against the other enemy, but it was just too late--the canny amœbus in command had learned his lesson and had already snapped on his zone of force.