And so it lay there, as if waiting to be straightened up and put back in place: cylindrical, two stories high, its black bulk encrusted by steel tracks and collars and the like. The tent only covered.a hundred meters or so of it; after that it ran on uncovered, east along the wide rounded plateau of the rim, until it disappeared over the rim’s outer edge, which formed their horizon — they could see nothing of the planet below. But out away from the town they could see better than ever that Pavonis Mons was huge — its rim alone was an impressive expanse, a doughnut of flat land perhaps thirty kilometers wide, from the abrupt inner edge of the caldera to the more gradual drop-off down the volcano’s flanks. Nothing of the rest of Mars could be seen from their vantage point, so it seemed they stood on a high circular ring world, under a dark lavender sky.

Just to the south of them, the new Socket was like a titanic concrete bunker, the new elevator cable rising out of it like an elevator cable, standing alone as if in some version of the Indian rope trick, thin and black and straight as a plumb line dropping down from heaven — visible for only a few tall skyscrapers’ worth of height, at most — and, given the wreckage they stood in, and the immensity of the volcano’s bare rocky peak, as fragile-looking as if it were a single carbon nanotube filament, rather than a bundle of billions of them, and the strongest structure ever made. “This is weird,” Art said, feeling hollow and unsettled.

After their tour of the ruins, Adrienne took them back to a plaza cafe in the middle of the new town, where they had lunch. Here they could have been in the heart of a fashionable district in any town anywhere — it could have been Houston or Tbilisi or Ottawa, in some neighborhood where a lot of noisy construction marked a fresh prosperity. When they went back to their rooms, the subway system was likewise familiar to the eye — and when they got out, the halls of the Praxis floors were those of a fine hotel. All utterly familiar — so much so that it was again a shock to walk into his room and look out the window and see the awesome sight of the caldera — the bare fact of Mars, immense and stony, seeming to exert a kind of vacuum pull on him through the window. And in fact if the windowpane were to break the pressure blowout would certainly suck him immediately into that space; an unlikely eventuality, but the image still gave him an unpleasant thrill. He closed the drapes.

And after that he kept the drapes closed, and tended to stay on the side of his room away from the window. In the mornings he dressed and left the room quickly, and attended orientation meetings run by Adrienne, which were joined by a score or so of new arrivals. After lunching with some of them, he spent his afternoons touring the town, working earnestly on his walking skills. One night he thought to send a coded report off to Fort: On Mars, going through orientation. Sheffield is a nice town. My room has a view. There was no reply.

Adrienne’s orientation took them to a number of Praxis buildings, both in Sheffield and up the east rim, to meet people in the transnational’s Martian operations. Praxis had much more of a presence on Mars than it did in America. During Art’s afternoon walks he tried to gauge the relative strengths of the transnationals, just by the little plates on the sides of the buildings. All the biggest transnats were there — Armscor, Subarashii, Oroco, Mitsubishi, The 7 Swedes, Shellalco, Gentine, and so on — each occupying a complex of buildings, or even entire neighborhoods of the town. Clearly they were all there because of the new elevator, which had made Sheffield once again the most important city on the planet. They were pouring money into the town, building submartian subdivisions, and even entire tent suburbs. The sheer wealth of the transnats was obvious in all the construction — and also, Art thought, in the way people moved: there were a lot of people bouncing around the streets just as clumsily as he was, newcomer businessmen or mining engineers or the like, concentrating with furrowed brow on the act of walking. It was no great trick to pick out the tall young natives, with their catlike coordination; but they were in a distinct minority in Sheffield, and Art wondered if that was true everywhere on Mars.

As for architecture, space under the tent was at a premium, and so the completed buildings were bulky, often cubical, occupying their lots right out to the street and right up to the tent. When all the construction was finished there would only be a network of ten triangular plazas, and the wide boulevards, and the curving park along the rim, to keep the town from being a continuous mass of squat skycrapers, faced with polished stone of various shades of red. It was a city built for business.

And it looked to Art like Praxis was going to get a good share of that business. Subarashii was the general contractor for the elevator, but Praxis was supplying the software as they had for the first elevator, and also some of the cars, and part of the security system. All these allocations, he learned, had been made by a committee called the United Nations Transitional Authority, supposedly part of the UN, but controlled by the transnats; and Praxis had been as aggressive on this committee as any of the others. William Fort might have been interested in bioinfrastructure, but the ordinary kind was obviously not outside Praxis’s field of operations; there were Praxis divisions building water supply systems, train pistes, canyon towns, wind-power generators, and areother-mal plants. The latter two were widely regarded as marginal endeavors, as the new orbiting solar collectors and a fusion plant in Xanthe were turning out so well, not to mention the older generation of integral fast reactors. But local energy sources were the specialty of the Praxis subsidiary Power From Below, and so that was what they did, working hard in the outback.

Praxis’s local salvage subsidiary, the Martian equivalent of Dumpmines, was called Ouroborous, and like Power From Below it was also fairly small. In truth, as the Ouroborous people were quick to tell Art when they met one morning, there was not a large garbage output on Mars; almost everything was recycled or put to use in creating agricultural soil, so each settlement’s dump was really more of a holding facility for miscellaneous materials, awaiting their particular reuse. Ouroborous therefore got its business by finding and collecting the garbage or sewage that was somehow recalcitrant — toxic, or orphaned, or simply inconvenient — and then finding ways to turn it to use.

The Ouroborous team in Sheffield occupied one floor of Praxis’s downtown skyscraper. The company had gotten its start excavating the the old town, before the ruins had been so unceremoniously shoved over the side. A man named Zafir headed the fallen cable salvage project, and he and Adrienne accompanied Art to the train station, where they got on a local train and took a short ride around to the east rim, to a line of suburb tents. One of the tents was the Ouroborous storage facility, and just outside it, among many other vehicles, was a truly gigantic mobile processing factory, called the Beast. The Beast made a SuperRathje look like a compact car — it was a building rather than a vehicle, and almost entirely robotic. Another Beast was already out processing the cable in west Tharsis, and Art was slated to go out and make an on-site inspection of it. So Zafir and a couple of technicians showed him around the inside of the training vehicle, ending up in a wide compartment on the top floor, where there were living quarters for any humans who might be visiting.

Zafir was enthusiastic about what the Beast out on west Tharsis had found. “Of course just recovering the carbon filament and the diamond gel helixes gives us a basic income stream,” he said. “And we are doing well with some brecciated exotics metamorphosed in the final hemisphere of the fall. But what you’ll be interested in are the buckyballs.” Zafir was an expert in these little carbon geodesic spheres called buckminsterfullerenes, and he waxed enthusiastic: “Temperatures and pressures in the west Tharsis zone of the fall turned out to be similar to those used in the arc-reactor-synthesis method of making fullerenes, and so there’s a hundred-kilometer stretch out there where the carbon on the bottom side of the cable consists almost entirely of buckyballs. Mostly sixties, but also some thirties, and a variety of superbuckies.” And some of the super-buckies had formed with atoms of other elements trapped inside their carbon cages. These “full fullerenes” were useful in composite manufacturing, but very expensive to make in the lab because of the high amounts of energy required. So they were a nice find. “It’s sorting out the various superbuckies where your ion chromatog-raphy will come in.”