Sax shivered, thinking of his own recent brush with cold; and 260 millibars was the pressure one would find on the peak of Everest. The others were already talking about other famous blowouts, including the time Hiranyagarba’s dome had fallen in its entirety under an ice rain, despite which no one had died.

Then they were descending over the great cratered high plain of Xanthe, coming down on the Da Vinci crater floor’s big sandy runway, which they had just started using during the revolution. The whole community had been preparing for years for the day when stealthing would become unnecessary, and now a big curve of copper-mirrored windows had been installed in the arc of the southern crater rim. There was a layer of snow in the bottom of the crater, which the central knob broke out of quite dramatically. It was possible they could arrange for a lake in the crater floor, with a central knob island, which would have as its horizon the circling cliffy hills of the crater rim. A circular canal could be built just under the rim cliffs, with radial canals connecting it to the inner lake; the resulting alternation of circular water and land would resemble Plato’s description of Atlantis. In this configuration Da Vinci could support, in near self-sufficiency, some twenty or thirty thousand people, Sax guessed; and there were scores of craters like Da Vinci. A commune of communes, each crater a city-state of sorts, its polis fully capable of supporting itself, of deciding what kind of culture it might have; and then with a vote in a global council of some kind. . . . No regional association larger than the level of the town, except for arrangements of local interchange . . . might it work?

Da Vinci made it seem like it might. The south arc of the rim was alive with arcades and wedge-shaped pavilions and the like, now all shot through with sunlight. Sax toured the whole complex one morning, visiting one lab after the next, and congratulating the occupants on the success of their preparations for a smooth removal of UNTA from Mars. Some political power came out of the end of a gun, after all, and some out of the look in the eye; and the look in the eye changed depending on whether a gun was pointed at it or not. They had spiked the guns, these people the saxaclones, and so they were in high spirits— happy to see him, and already looking for different work— back to basic research, or figuring out uses for the new materials that Spencer’s alchemists were constantly churning out; or studying the terraforming problem.