“Do you remember, Mona, how the tetrarchs first came to Earth--how friendly they were and how they loaded us with those amazing labor-eliminating gadgets? Press a button and everything was done--power for our gyros, heat for our buildings, force for our machines--anything and everything. With all our work eliminated we lost our watchfulness. They never let us know what powered the gadgets--we never knew about gryxon power until the tetrarchs took over. “We found out about gryxon then--in the mines. Once it’s sheathed by radium and the radium sheathed with lead--it’s harmless. But--when human life is used to handle the raw ore--!” The vibrant timbre of Rod’s voice seemed to die away to death’s whisper, “Well, we all expect to die when we’re twenty-five ... and time’s passing. Try weighing what you might loosely call the human race against one brother! “And as for you--” Rod stepped forward quickly and slammed his fist against the air tank attached to Koler’s space suit. He wrenched it loose and threw it away. Not waiting to see the result, he stepped out of the aperture and gave the guard the same treatment. He raced through the city, wondering why he was not pursued. Then it came to him. There would be a Hunt. As he ran across rocky ground he wondered how Koler was taking to a silica diet. His course was hazily sketched in his mind. The smuggled note that had started him from Earth had not been too specific. It couldn’t have been. There was too much chance of its being intercepted. But he had a good working knowledge of Tetrarch’s surface. The problem was to get to the Survivors--those who had somehow escaped the gryxon mines and escaped the hunting tetrarchians--and in getting to them he had to throw his pursuers off the trail. There was a test in this, he was sure. He thought he had certain clues to that. Why, for instance, did a tetrarch with a slug in him keep on fighting? Why did the unearthly glow precede the coming of the guards? He felt he ought to be glad about that eerie flash. It was a warning--something like a rattlesnake’s. His course led him to rocky foothills. He had skirted them when another gnawing thought came. When did Mona adopt a brother? He’d never known of one. He shrugged the thought aside. He was coming to a broad pass. He kept his course straight, for it was still dark. When dawn came he would seek cover--or did darkness mean anything to the tetrarchians? It probably didn’t. He covered the pass and worked his way up the far right of three towering mountains. It was cold--colder even than the bitter keenness of the level lands. He notched the heating element in his suit to the top position and continued his climb. In the deep darkness that preceded dawn he felt his way along the edge of narrow, jagged ravines. The swirling sands made sight impossible. His progress became slower.