He was convinced that it was deserted now. There was a complete deadness to it, a stone and metal tower rising abruptly from a snow-blanketed plain, long abandoned, long forgotten. And descending lower, he could make out the geometric patterns of low structures and broad avenues, but with a skeletal emptiness about them, the roofs collapsed, the walls themselves in many places having toppled into the general ruin. A dead city, certainly, yet once it must have been a metropolis, culminating in its strange, massive tower before it died.
"Forgotten names from forgotten histories came back to me," he said. "The northwest coast—not Vancouver? Not Seattle? No, for both of them had been upon the coast itself. Spokane, then? Or possibly some city that had flourished after the establishment of the Curtain? But it did not matter, the place was dead, with the anonymity of the dead. A graveyard of a civilization that had been the mightiest on earth. Yet the proof that this civilization actually had existed—that it was no myth—was enormously stimulating to me. It was my second big moment."
The tower and the ruined city had taken his attention from the business of flying. Now suddenly he was startled by the rapid-fire of his scintillometer. It was recording .400 milliroentgens an hour—unendurable!
"The dead," said O'Hara, "were reaching out for me. They wanted me, an alien probing through the skies above their tomb. And I felt their hostility, as if a shower of warheads had come roaring up. The contamination was as murderous as any warheads would have been."
The tautness of his steep climb skyward and sharp swerve back toward the spinal cord of the continent precluded any further observations. He was now acutely alarmed. He expected at any moment to discover upon his body the raw violence of radioactive burns, he anticipated bleeding and there was at the hinges of his jaws a definite sensation of nausea. Yet moments passed without development of these symptoms. The nausea abated. He was not stricken yet, or if he was, the effects were not yet obvious. And this raised possibilities of conditioning to the contamination that had never been explored—that no one, in the world he knew, had dared to explore. It might yet prove to be that man could exist in these extremes of radioactivity.
Large mottled patches now were appearing between the pale blue-white stretches of endless snow. The mountain peaks and the high plateaus still presented their heavily drifted appearance, but in the deeper valleys an occasional ice-free river twisted, seeking its outlet either toward the east or west—the east, O'Hara remembered, would lead to the intricate arterial system that would at last merge into the Mississippi River, the continental sewer that dumped its burden of silt and debris into the swampland delta of—what was it? Louisiana? The whole once-familiar pattern of maps he had intensely studied as a child now was coming back vividly—the two mountain systems, Appalachian and Rockies, the great valley of the Mississippi, the Atlantic and Pacific coastlands, the spider web of fabulous cities, names like New York and Washington, Chicago and Kansas City, Los Angeles and San Francisco, and somewhere in these Rockies which he was now following were—or had been—Salt Lake City and Denver.
There was a definite excitement in these names that for O'Hara rolled back the drab present to that glittering past, when the word tomorrow had meant more than a repetition of today.
O'Hara felt positive now that he had established a second major fact. For almost two hours he had been flying these forbidden skies, yet no patrol—save the atomic radiation of the dead city—had so far challenged him. It was inconceivable that any important civilization could exist upon the northernmost of the two Lost Continents without patrolling its skies, and consequently, if a civilization did exist, it must have shifted to the south, leaving these wastes. But for some minutes past, he had observed a peculiar series of geometric designs, resembling the drawings of ancient Cretan labyrinths, far below him on the frozen surface. He now was approaching another of these, extending for miles upon the floor of a wide valley, and very cautiously, with his eyes constantly flicking back to his scintillometer, he began to descend toward it, diving.
As rapidly, his milliroentgen count began to climb, reaching .290 within the first five thousand feet of descent, then to .300 when his altitude was down to 30,000 and jumping very sharply at 24,000 feet to .325. The strange labyrinth was much too hot for inspection. But the regularity of its form seemed proof that it was man-made, and that decided O'Hara. He continued down until his altimeter registered 5,000 feet.
The labyrinth's pattern was precise. It was composed of an almost infinite number of thick parallel lines, joined at the ends, so that it actually resembled an endless pipe, though various segments of it were colored in a multiplicity of pastel shades—a vast farm of pipes, reaching for miles across the valley's floor, its purpose not apparent to O'Hara. His milliroentgen count now was approaching .400, and again he made that steep climb back to 40,000 feet.