But even the substance of those arms, the metal itself, looked indefinite and eye-hurting at the edges, as though it was partly fourth-dimensional, or something. Both men grasped the truth. Here was that million-year advancement of science that they'd talked about with such thrilled fascination, in the stuffy bar of the Spacemen's Haven, back in Ganymede City. But Ganymede City, with all its human crudeness and inefficiency, seemed like a lost, happy legend, now, to Arnold and Harwich. Far, far away, and dim. For here was dread wonder to eclipse it. Futurian fact! Physical principles of such a miraculous order that mankind had scarcely dreamed of their outer fringes yet, were functioning here. The flat machine advanced. But it was only instinct working, when the two men crouched away from it a little. It was useless to fight; it was useless to run. "Get away, you!" Paul Arnold grumbled dully to the mechanism. "Beat it! Scram." And Harwich was reacting in a similar manner. "What the hell!" he stammered. "What are you trying to do with us." It was almost funny--the ineffectual, confused protest of those two men. They were like children too lost in their new environment to know what was dangerous and what was not. Misty, lavender tentacles reached out and grasped them carefully. They were lifted from the floor of the cage like babes. Once Harwich's great freckled arms tautened, as though he was going to battle the monstrous miracle that held him. But futility checked the urge. Where was there anything to win by struggling, now? And how could a mere man win anyway, against soft-moving mechanical power, that should belong to the far future? Oddly the tentacles were warm and tingling, not cold like you'd think metal should be. And so Arnold and Harwich submitted to a paternal, mechanical dominance, regretfully, because there was nothing else to do. It hurt their sense of freedom, but where was there any alternative? Still floating a little off the tile pavement of the cage, the machine carried the two men easily to the opening in the floor, and glided down into a crystal-roofed tunnel. There it began to accelerate swiftly, flying with bullet-like speed, a foot or so above the glass bottom of the passage. The tunnel's roof was transparent as air. Through it, Harwich and Arnold could see that they were nearing the Tower rapidly. After only a moment of whizzing, breath-taking flight, they had arrived within that great, enigmatic edifice, for the passage entered its base. There, in an eerie half-twilight, the flat little machine released the two humans whom it had brought here, to the Tower.