It lay a little askew upon the ground, seeming to be partly buried in the earth. A hundred feet and more in length, it was even more obviously a monstrosity as he looked at it in the bright light of day. But now it was not alone. Beside it a white tower reared upward. Pure white and glistening in the sunshine, a bulging, uneven shaft rose a hundred feet sheer. It looked as solid as marble. Its purpose was unguessable. There was a huge, fan-shaped space where the vegetation about the rocket-ship was colored a vivid red. In air-photos, the rocket-ship would look remarkably like something from another planet. But nearby, Thorn could see a lazy trickle of fuel-fumes from a port-pipe on one side of the monster.... "That tower is nothing but cellate foam, which hardens. And Sylva! See?" She came cautiously through the brushwood and looked down. She shivered a little. From here they could see beneath the bows of the rocket-ship. And there was a name there, in the Cyrillic alphabet which was the official written language of the Com-Pubs. Here, on United Nations soil, it was insolent. It boasted that the red ship came, not from an alien planet, but from a nation more alien still to all the United Nations stood for. The Com-Pubs--the Union of Communist Republics--were neither communistic nor republics, but they were much more dangerous to the United Nations than any mere Martians would have been. "We'll have some heavy ships here to investigate, soon," said Thorn grimly. "Then I'll signal!" * * * * * He flung back his head. High up and far away, beyond that invisible barrier against which Watch-planes had flung themselves in vain, there were tiny motes in mid-air. These were Watch planes too, hovering outside the obstacle they could not see, but which even hexynitrate bombs could not break through. And very far away indeed there was a swiftly-moving small dark cloud. As Thorn watched, that cloud drew close. As his eyes glowed, it resolved itself into its component specks. Small, two-man patrol-scouts. Larger, ten-man cruisers of the air. Huge, massive dreadnaughts of the blue. A complete combat-squadron of the United Nations Fighting Forces was sweeping to position about the dome of force above the rocket-ship. The scouts swept forward in a tiny, whirling cloud. They sheered away from something invisible. One of them dropped a smoking object. It emitted a vast cloud of paper, which the wind caught and swept away, and suddenly wrapped about a definite section of an arc. More and more of the tiny smoke-bombs released their masses of cloudlike stuff. In mid-air a dome began to take form, outlined by the trailing streaks of gray. It began to be more definitely traced by interlinings. An aerial lattice spread about a portion of a six-mile hemisphere. The top was fifteen thousand feet above the rocket-ship, twenty-five thousand feet from sea-level, as high as Mount Everest itself.