He had intended to go through the check list that the doctor had given him, but that awesome view made it impossible. He stood rooted to the spot, only shifting his unaccustomed weight from one foot to the other as hitherto unknown muscles registered their complaints.

Port Van Allen circled the globe every two hours, and also rotated on its own axis three times a minute. After a while, Duncan found that he could ignore the station’s own spin; his mind was able to cancel it out, like an irrelevant background noise or a persistent but neutral odor. Once he had achieved this mental attitude, he could imagine that he was alone in space, a human satellite racing along the Equator from night into day. For the

Earth was waxing visibly even as he watched, the curved line of dawn moving steadily away from him as he hurtled into the east.

As usual, there was little land visible, and what could be seen through or between the clouds seemed to have no relationship to any maps. And from this altitude there was not the slightest sign of life-still less of intelligence. it was very hard to believe that most of human history had taken place beneath that blanket of brilliant white, and that, until a mere three hundred years ago, no man had ever risen above it.

He was still searching for signs of life when the disc started to contrast to a crescent once more, and the public-address system called on all passengers for Earth to report to the shuttle embarkation area, Elevators

Two and Three.

He just had time to stop at the “Last Chance” toilet-almost as famous

as the lounge windows-and then he was down by elevator again, back into the weightless world of the station’s hub, where the Earth-to-orbit shuttle was being readied for its return journey.

There were no windows here, but each passenger had his own vision screen, on the back of the seat in front of hina, and could switch to forward, rear, or downward as preferred. The choice was not completely free, though this fact was not widely advertised. Images that were likely to be too disturbing like the final moments of docking or touchdown were thoughtfully censored by the ship’s computer.

It was pleasant to be weightless again-if only during the fifty minutes needed for the fall down to the edge of the atmosphere-and to watch the

Earth slowly changing from a planet to a world. The curve of the horizon became flatter and flatter; there were fleeting glimpses of islands and the spiral nebula of a great storm, raging in silence far below. Then at last a feature that Duncan could recognize-the characteristic narrow isthmus of the California coastline, as the shuttle dropped out of the Pacific skies for its final landfall, still the width of a continent away.

He felt himself sinking deeper and deeper into the superbly padded seat, which spread the load so evenly over his body that there was the minimum of discomfort. But it was hard to breathe, until he remembered the “Advice to

Passengers” he had finally managed to read. Don’t try to inhale deeply, it had said; take short, sharp pants, to reduce the strain on the chest muscles. He tried it, and it worked.

Now there was a gentle buffeting and a distant roar, and the vision screen flashed into momentary flame, then switched automatically from the fires of reentry to the view astern. The canyons and deserts dwindled behind, to be replaced by a group of lakes-obviously artificial, with the tiny white flecks of sailboats clearly visible. He caught a glimpse of the huge

V-shaped wake, kilometers long, of some vessel going at great speed over the water, although from this altitude it seemed completely motionless.

Then the scene changed with an abruptness that took him by surprise.

He might have been flying over the ocean once more, so uniform was the view below. Still so high that he could not see the individual trees, he was passing over the endless forests of the American Midwest.

Here indeed was proof of Life, on a scale such as he had never imagined. On all of Titan, there were fewer than a hundred trees, cherished and protected with loving care. Spread out beneath him now were incomputable millions.

Somewhere, Duncan had encountered the phrase “primeval forest,” and now it flashed again into his mind. So must the Earth have looked in the ancient days, before Man had set to work upon it with fire and axe. Now, with the ending of the brief Agricultural Age, much of the planet was reverting to something like its original state.

Though the fact was very hard to believe, Duncan knew perfectly well that the “primeval forest” lying endlessly beneath him was not much older than

Grandfather. Only two centuries ago, this had all been farmland, divided into enormous checkerboards and covered in the autumn with golden grain. (That concept of seasons was another local reality he found extremely difficult to grasp…. ) There were still plenty of farms in the world, run by eccentric hobbyists or biological research organizations, but the disasters of the twentieth century had taught men never again to rely on a technology that, at its very best, had an efficiency of barely one percent.

The sun was sinking, driven down into the west with unnatural speed by the shuttle’s velocity. It clung to the horizon for a few seconds, then winked out. For perhaps a minute longer the forest was still visible; then it faded into obscurity.

But not into darkness. As if by magic, faint lines of light had appeared on the land below-spiders’ webs of luminosity, stretching as far as the eye could see. Sometimes three or four lines would meet at a single glowing knot. There were also isolated islands of phosphorescence, apparently unconnected with the main network. Here was further proof of Man’s existence; that great forest was a much

busier place than it appeared to be by daylight. Yet Duncan could not help comparing this modest display with pictures he had seen from the early Atomic Age, when millions of square kilometers blazed at night with such brilliance that men could no longer see the stars.

He suddenly became aware of a compact constellation of flashing lights, moving independently of the glimmering landscape far below. For a moment, he was baffled; then he realized that he was watching some great airship, cruising not much faster than a cloud with its cargo of freight or passengers. This was one experience Titan could not provide. He determined to enjoy it as soon as the opportunity arose.

And there was a city-quite a big one, at least a hundred thousand people.

The shuttle was now so low that he could make out blocks of buildings, roads, parks, and a stadium blazing with light, presumably the scene of some sporting event. The city fell astern, and a few minutes later everything was lost in a gray mist, lit by occasional flashes of lightning, not very impressive by the standards of Titan. Inside the cabin, Duncan could hear nothing of the storm through which they were now flying, but the vibration of the engines had taken a new note and he could sense that the ship was dropping rapidly. Nevertheless, he was taken completely by surprise when there was a sudden surge of weight, the slightest of jolt sand there on the screen was a sea of wet concrete, a confusion of lights, and half a dozen buses and service vehicles scurrying around in the driving rain.

After thirty years, Duncan Makenzie had returned to the world where he was born, but which he had never seen…. Part III

Terra

WASHINGTON, D.C.

“Sorry about the weather,” said George Washington. “We used to have local climate control, but gave it up after an Independence Day parade was blocked by snow.”

Duncan laughed dutifully, though he was not quite sure if he was supposed to believe this.

“I don’t mind,” he said. “It’s all new to me. I’ve never seen rain before.”