Nadia went into her habitat in the trailer park for a standing lunch. Then she was out again, to the site of the permanent habitat. The floor of the trench had been almost leveled in her absence. She stood on the edge of the hole, looking down in it. They were going to build to a design that she liked tremendously, one she had worked on herself in Antarctica and on the Ares: a simple line of barrel-vaulted chambers, sharing adjacent walls. By setting them in the trench the chambers would be half-buried to begin with; then when completed they would be covered by ten meters of sandbagged regolith, to stop radiation and also, because they planned to pressurize to 450 millibars, to keep the buildings from exploding. Local materials were all they needed for the exteriors of these buildings: Portland cement and bricks were it, basically, with plastic liner in some places to insure the seal.

Unfortunately the brickmakers were having some trouble, and they gave Nadia a call. Nadia’s patience was running short, and she groaned. “We travel all the way to Mars and you can’t make bricks?”

“It’s not that we can’t make bricks,” said Gene. “It’s just that I don’t like them.” The brickmaking factory mixed clays and sulphur extracted from the regolith, and this preparation was poured into brick molds, and baked until the sulphur began to polymerize, and then as the bricks cooled they were compressed a bit in another part of the machine. The resulting blackish-red bricks had a tensile strength that was technically adequate for use in the barrel vaults, but Gene wasn’t happy. “We don’t want to be at minimum values for heavy roofs over our heads,” he said. “What if we pile one too many sandbag on top of it, or if we get a little marsquake? I don’t like it.”

After some thought Nadia said, “Add nylon.”

“What?”

“Go out and find the parachutes from the freight drops, and shred them real fine, and add them to the clay. That’ll help their tensile strength.”

“Very true,” Gene said, after a pause. “Good idea! Think we can find the parachutes?”

“They must be east of here somewhere.”

So they had finally found a job for the geologists that actually helped the construction effort. Ann and Simon and Phyllis and Sasha and Igor drove long-distance rovers over the horizon to east of the base, searching and surveying far past Chernobyl; and in the next week they found almost forty parachutes, each one representing a few hundred kilos of useful nylon.

One day they came back excited, having reached Ganges Catena, a series of sinkholes in the plain a hundred kilometers to the southeast. “It was strange,” Igor said, “because you can’t see them until the last minute, and then they’re like huge funnels, about ten kilometers across and a couple deep, eight or nine in a row, each smaller and shallower. Fantastic. They’re probably thermokarsts, but they’re so big it’s hard to believe it.”

Sasha said, “It’s nice to see such a distance, after all this near horizon stuff.”

“They’re thermokarsts,” Ann said. But they had drilled and found no water. This was a getting to be a concern; they hadn’t found any water to speak of in the ground, no matter how far down they drilled; it forced them to rely on the supplies from the air miners.

Nadia shrugged. The air miners were pretty tough. She wanted to think about her vaults. The new improved bricks were appearing, and she had started the robots building the walls and roofs. The brick factory filled little robot cars, which rolled like toy rovers across the plain to cranes at the site; the cranes pulled out bricks one by one, and placed them on cold mortar spread by another set of robots. The system worked so well that soon the bottleneck became brick production itself. Nadia would have been pleased, if she had had more faith in the robots; these seemed okay, but her experiences with robots in the years on Novy Mir had made her wary. They were great if everything went perfectly, but nothing ever went perfectly, and it was hard to program them with decision algorithms that didn’t either make them so cautious that they froze every minute, or so uncontrolled that they could commit unbelievable acts of stupidity, repeating an error a thousand times and magnifying a small glitch into a giant blunder, as in Maya’s emotional life. You got what you put into robots; but even the best were mindless idiots.

* * *

One evening Maya snagged her out in her tool room and asked her to switch to a private band. “Michel is useless,” she complained. “I’m really having a hard time, and he won’t even talk to me! You’re the only one I trust, Nadia. Yesterday I told Frank that I thought John was trying to undercut his authority in Houston, but that he shouldn’t tell anyone I thought so, and the very next day John was asking me why I thought he was bothering Frank. There’s no one who will just listen and stay quiet!”

Nadia nodded, rolling her eyes. Finally she said “Sorry, Maya, I have to go talk to Hiroko about a leak they can’t find.” She banged her faceplate lightly against Maya’s-symbol for a kiss on the cheek-and switched to the common band and took off. Enough was enough. It was infinitely more interesting to talk to Hiroko; real conversations, about real problems in the real world. Hiroko was asking Nadia for help almost every day, and Nadia liked that, because Hiroko was brilliant, and since landfall had obviously raised her estimate of Nadia’s abilities. Mutual professional respect, a great maker of friendships. And so nice to talk nothing but business. Hermetic seals, lock mechanisms, thermal engineering, glass polarization, farm/human interfaces (Hiroko’s talk was always a few steps ahead of the game); these topics were a great relief after all the emotional whispered conferences with Maya, endless sessions about who liked Maya and who didn’t like Maya, about how Maya felt about this and that, and who had hurt her feelings that day… bah. Hiroko was never strange, except when she would say something Nadia didn’t know how to deal with, like “Mars will tell us what it wants and then we’ll have to do it.” What could you say to something like that? But Hiroko would just smile her big smile, and laugh at Nadia’s shrug.

At night the talk still went everywhere, vehement, absorbed, unselfconscious. Dmitri and Samantha were sure that they could soon introduce GEMs into the regolith that would survive, but they would have to get permission first from the UN. Nadia herself found the idea alarming; it made the chemical engineering in the factories look relatively straightforward, more like brickmaking than the dangerous acts of creation Samantha was proposing… Although the alchemists were performing some pretty creative things themselves. Almost every day they came back to the trailer park with samples of new materials: sulphuric acid, sorel cements for the vault mortar, ammonium nitrate explosives, a calcium cyanamide rover fuel, polysulfide rubber, silicon-based hyperacids, emulsifying agents, a selection of test tubes holding trace elements extracted from the salts; and, most recently, clear glass. This last was a coup, as earlier attempts at glassmaking had produced only black glass. But stripping silicate feedstocks of their iron content had done the trick; and so one night they sat in the trailer passing around small wavy sheets of glass, the glass itself filled with bubbles and irregularities, like something out of the seventeenth century.

* * *

When they got the first chamber buried and pressurized, Nadia walked around inside it with her helmet off, sniffing the air. It was pressurized to 450 millibars, same as the helmets and the trailer park, with an oxygen-nitrogen-argon mix, and warmed to about fifteen degrees Centigrade. It felt great.

The chamber had been divided into two stories by a floor of bamboo trunks, set in a slot in the brick wall two and a half meters overhead. The segmented cylinders made a sweet green ceiling, lit by neon tubes hung under them. Against one wall was a magnesium and bamboo staircase, leading through a hole to the upper story. She climbed up to have a look. Split bamboo over the trunks made a fairly flat green floor. The ceiling was brick, rounded and low. Up there they would locate the bedrooms and bathroom; the lower floor would be living room and kitchen. Maya and Simon had already put up wall hangings, made of nylon from the salvaged parachutes. There were no windows; lighting came from only from the neon bulbs. Nadia disliked this fact, and in the larger habitat she was already planning, there would be windows in almost every room. But first things first. For the time being these windowless chambers were the best they could do. And a big improvement over the trailer park, after all.