"What are you, anyway?" blazed Costigan, helpless but enraged beyond caution. "I have heard of mad scientists who tried to destroy the Earth, and of equally mad geniuses who thought themselves Napoleons capable of conquering even the Solar System. Whichever you are, you should know that you can't get away with it." "I am neither. I am, however, a scientist, and I direct many other scientists. I am not mad. You have undoubtedly noticed several peculiar features of this place?" "Yes, particularly the artificial gravity and those screens. An ordinary ether-wall is opaque in one direction, and doesn't bar matter--yours are transparent both ways and something more than impenetrable to matter. How do you do it?" "You could not understand them if I explained them to you, and they are merely two of our smaller developments. I do not intend to destroy your planet Earth; I have no desire to rule over masses of futile and brainless men. I have, however, certain ends of my own in view. To accomplish my plans I require hundreds of millions in gold and other hundreds of millions in uranium, thorium, and radium; all of which I shall take from the planets of this Solar System before I leave it. I shall take them in spite of the puerile efforts of the fleets of your Triplanetary League. "This structure was designed by me and built under my direction. It is protected from meteorites by forces of my devising. It is indetectable and invisible--ether waves are bent around it without loss or distortion. I am discussing these points at such length so that you may realize exactly your position. As I have intimated, you can be of assistance to me if you will." "Now just what could you offer any _man_ to make him join your outfit?" demanded Costigan, venomously. "Many things," Roger's cold tone betrayed no emotion, no recognition of Costigan's open and bitter contempt. "I have under me many men, bound to me by many ties. Needs, wants, longings, and desires differ from man to man, and I can satisfy practically any of them. Many men take delight in the society of young and beautiful women, but there are other urges which I have found quite efficient. Greed, thirst for fame, longing for power, and so on, including many qualities usually regarded as 'noble.' And what I promise, I deliver. I demand only loyalty to me, and that only in certain things and for a relatively short period. In all else, my men do as they please. In conclusion, I can use you two conveniently, but I do not need you. Therefore you may choose now between my service and--the alternative." "Exactly what is the alternative?" "We will not go into that. Suffice it to say that it has to do with a minor research, which is not progressing satisfactorily. It will result in your extinction, and perhaps I should mention that that extinction will not be particularly pleasant." "I say NO, you...." Bradley roared. He intended to give an unexpurgated classification, but was rudely interrupted.