This caused a clamor. Through it Nadia said to Sax, “Let’s tell Hunt Mesa the plan, and get down there and meet the masks.”

Sax nodded.

4

Between Mangalavid and the wristpads they were able to make a very rapid dispersal of the plan to the population of Burroughs, while driving down in a big caravan from Du Martheray to a low line of hillocks just southwest of the city. Soon after their arrival, the two planes bringing the CO2 masks from Da Vinci swooped down over Syrtis, and landed on a swept area of the plains just outside the western apron of the tent wall. On the other side of the city observers on top of Double Decker Butte had already reported sighting the flood, coming in from a bit north of east: dark brown ice-flecked water, pouring down the low crease that inside the city wall was occupied by Canal Park. And the news about South Station had proved true; the piste equipment had been wrecked, by an explosion in the linear induction generator. No one knew for sure who had done it, but it was done, the trains immobilized.

So as Zeyk’s Arabs drove the boxes of masks to West, Southwest, and South gates, there were huge crowds already congregating inside each of them, everyone dressed either in walkers with heating filaments, or in the heaviest clothes they had— none too heavy for the job at hand, Nadia judged as she went in Southwest Gate, and passed out facemasks from boxes. These days many people in Burroughs went out on the surface so seldom that they rented walkers to do so. But there were not enough walkers to dress everyone, and they had to go with people’s interior coats, which were fairly lightweight, and usually deficient in headgear. The message about the evacuation had been sent out with a warning to dress for 255Âdeg;K, however, and so most people were layered in several garments, appearing thick-limbed and thick-torsoed.

Each gate lock could pass five hundred people every five minutes— they were big locks— but with thousands of people waiting inside, and the crowds growing as Saturday morning wore on, it was not anywhere near fast enough. The masks had been distributed through the crowds, and it seemed certain to Nadia that at this point everyone had one. It was unlikely that anyone in the city was unaware of the emergency. And so she went around to Zeyk, and Sax, and Maya and Michel, and all the other people she knew that she saw, saying, “We should cut the tent wall and just walk out. I’m going to cut the tent wall now.” And no one disagreed.