"I have been trying for years to learn something of their nature, but beyond working out a method for their detection and a method of possible analysis that may or may not succeed I can do nothing with them. It is perfectly evident, however, that they lie below the level of the ether, and therefore have a velocity of propagation infinitely greater than that of light. You may see for yourself, then, that to a science able to guide and control them, to make them act as carrier waves for any other desired frequency--to do all of which the Overlord has this day shown himself capable--they should theoretically afford weapons before which our every defense would be precisely as efficacious as so much vacuum. Think a moment! You know that we know nothing fundamental concerning even our servants, the sub-rays. If we really knew them we could utilize them in thousands of ways as yet unknown to us. We work with the merest handful of forces, empirically, while it is practically certain that the enemy has at his command the entire spectrum, visible and invisible, embracing untold thousands of bands of unknown but terrific potentiality." "But he spoke of a calculated time necessary before our answer could be received. They must, then, be using vibrations in the ether." "Not necessarily--not even probably. Would we ourselves reveal unnecessarily to an enemy the possession of such rays? Do not be childish. No, Fenimol, and you, Fenor of the Fenachrone, instant and headlong flight is our only hope of present salvation and of ultimate triumph--flight to a far distant Galaxy, since upon no point in this one shall we be safe from the infra-beams of that self-styled Overlord." "You snivelling coward! You pusillanimous bookworm!" Fenor had regained his customary spirit as the scientist explained upon what grounds his fears were based. "Upon such a tenuous fabric of evidence would you have such a people as ours turn tail like beaten hounds? Because, forsooth, you detect a peculiar vibration in the air, will you have it that we are to be invaded and destroyed forthwith by a race of supernatural ability? Bah! Your calamity-howling clan has delayed the Day of Conquest from year to year--I more than half believe that you yourself or some other treacherous poltroon of your ignominious breed prepared and sent that warning, in a weak and rat-brained attempt to frighten us into again postponing the Day of Conquest! Know now, spineless weakling, that the time is ripe, and that the Fenachrone in their might are about to strike. But you, foul traducer of your emperor, shall die the death of the cur you are!" The hand within his tunic moved and a vibrator burst into operation.