The Spacers didn’t leave, of course. It wasn’t even necessary for them to bring any of their offensive weapons into play. Earth’s outmoded fleet had long since learned that it was suicide to venture near any Outer World ship. Earth planes that had ventured over the Spacetown area in the very early days of its establishment had simply disappeared. At the most, a shredded wing tip might tumble down to Earth.

And no mob could be so maddened as to forget the effect of the subetheric hand disruptors used on Earthmen in the wars of a century ago.

So the Spacers sat behind their barrier, which itself was the product of their own advanced science, and that no method existed on Earth of breaking. They just waited stolidly on the other side of the barrier until the City quieted the mob with somno vapor and retch gas. The below-level penitentiaries rattled afterward with ringleaders, malcontents, and people who had been picked up simply because they were nearest at hand. After a while they were all set free.

After a proper interval, the Spacers eased their restrictions. The barrier was removed and the City Police entrusted with the protection of Spacetown’s isolation. Most important of all, the medical examination was more unobtrusive.

Now, thought Baley, things might take a reverse trend. If the Spacers seriously thought that an Earthman had entered Spacetown and committed murder, the barrier might go up again. It would be bad. He lifted himself onto the expressway platform, made his way through the standees to the tight spiral ramp that led to the upper level, and there sat down. He didn’t put his rating ticket in his hatband till they passed the last of the Hudson Sections. A C-5 had no seat rights east of the Hudson and west of Long Island, and although there was ample seating available at the moment, one of the way guards would have automatically ousted him. People were increasingly petty about rating privileges and, in all honesty, Baley lumped himself in with “people.”

The air made the characteristic whistling noise as it frictioned off the curved windshields set up above the back of every seat. It made talking a chore, but it was no bar to thinking when you were used to it.

Most Earthmen were Medievalists in one way or another. It was an easy thing to be when it meant looking back to a time when Earth was the world and not just one of fifty. The misfit one of fifty at that. Baley’s head snapped to the right at the sound of a female shriek. A woman had dropped her handbag; he saw it for an instant, a pastel pink blob against the dull gray of the strips. A passenger hurrying from the expressway must inadvertently have kicked it in the direction of deceleration and now the owner was whirling away from her property.

A corner of Baley’s mouth quirked. She might catch up with it, if she were clever enough to hurry to a strip that moved slower still and if other feet did not kick it this way or that. He would never know whether she would or not. The scene was half a mile to the rear, already.

Chances were she wouldn’t. It had been calculated that, on the average, something was dropped on the strips every three minutes somewhere in the City and not recovered. The Lost and Found Department was a huge proposition. It was just one more complication of modern life.

Baley thought: It was simpler once. Everything was simpler. That’s what makes Medievalists.

Medievalism took different forms. To the unimaginative Julius Enderby, it meant the adoption of archaisms. Spectacles! Windows!

To Baley, it was a study of history. Particularly the history of folkways.

The City now! New York City in which he lived and had his being. Larger than any City but Los Angeles. More populous than any but Shanghai. It was only three centuries old.

To be sure, something had existed in the same geographic area before then that had been called New York City. That primitive gathering of population had existed for three thousand years, not three hundred, but it hadn’t been a City.

There were no Cities then. There were just huddles of dwelling places large and small, open to the air. They were something like the Spacer’s Domes, only much different, of course. These huddles (the largest barely reached ten million in population and most never reached one million) were scattered all over Earth by the thousands. By modern standards, they had been completely inefficient, economically. Efficiency had been forced on Earth with increasing population. Two billion people, three billion, even five billion could be supported by the planet by progressive lowering of the standard of living. When the population reaches eight billion, however, semi-starvation becomes too much like the real thing. A radical change had to take place in man’s culture, particularly when it turned out that the Outer Worlds (which had merely been Earth’s colonies a thousand years before) were tremendously serious in their immigration restrictions.

The radical change had been the gradual formation of the Cities over a thousand years of Earth’s history. Efficiency implied bigness. Even in Medieval times that had been realized, perhaps unconsciously. Home industry gave way to factories and factories to continental industries.

Think of the inefficiency of a hundred thousand houses for a hundred thousand families as compared with a hundred-thousand-unit Section; a book-film collection in each house as compared with a Section film concentrate; independent video for each family as compared with video-piping systems.

For that matter, take the simple folly of endless duplication of kitchens and bathrooms as compared with the thoroughly efficient diners and shower rooms made possible by City culture.

More and more the villages, towns, and “cities” of Earth died and were swallowed by the Cities. Even the early prospects of atomic war only slowed the trend. With the invention of the force shield, the trend became a headlong race.

City culture meant optimum distribution of food, increasing utilization of yeasts and hydroponics. New York City spread over two thousand square miles and at the last census its population was well over twenty million. There were some eight hundred Cities on Earth, average population, ten million.

Each City became a semiautonomous unit, economically all but self-sufficient. It could roof itself in, gird itself about, burrow itself under. It became a steel cave, a tremendous, self-contained cave of steel and concrete.

It could lay itself out scientifically. At the center was the enormous complex of administrative offices. In careful orientation to one another and to the whole were the large residential Sections connected and interlaced by the expressway and the localways. Toward the outskirts were the factories, the hydroponic plants, the yeast-culture vats, the power plants. Through all the melee were the water pipes and sewage ducts, schools, prisons and shops, power lines and communication beams.

There was no doubt about it: the City was the culmination of man’s mastery over the environment. Not space travel, not the fifty colonized worlds that were now so haughtily independent, but the City.

Practically none of Earth’s population lived outside the Cities. Outside was the wilderness, the open sky that few men could face with anything like equanimity. To be sure, the open space was necessary. It held the water that men must have, the coal and the wood that were the ultimate raw materials for plastics and for the eternally growing yeast. (Petroleum had long since gone, but oil-rich strains of yeast were an adequate substitute.) The land between the Cities still held the mines, and was still used to a larger extent than most men realized for growing food and grazing stock. It was inefficient, but beef, pork, and grain always found a luxury market and could be used for export purposes.