He was still searching for signs of life when the disc started to contract 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 of 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 him, 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 island 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 gently buffeting and a distant roar, and the vision screen flared into momentary
flame, then switched automatically from the fires of reentry to the view astern. The canyons and deserts dwindled behind, to be replace 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 to 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