On the second day of his drive, Art got off the immense cone of Pavonis, and onto the Tharsis bulge proper. Here the ground was much more littered than the volcano’s side had been with loose rock, and meteor craters. And down here, everything was blanketed with a drift of snow and sand, in a mix that looked like equal shares of both. This was the firn slope of west Tharsis, an area where storms coming in from the west frequently dumped loads of snow, which never melted but instead built up year by year, packing down the snow on the bottom. So far the pack consisted only of crushed snow, called firn, but after more years of compaction the lowest layers would be ice, and the slopes glaciers.

Now the slopes were still punctuated by big rocks sticking out of the firn, and small crater rings, the craters mostly less than a kilometer across, and looking as fresh as if they had been blasted the day before, except for the sandy snow now filling them.

When he was still many kilometers away, Art caught sight of the Beast salvaging the cable. The top of it appeared over the western horizon, and over the next hour the rest of it reared into view. Out on the vast empty slope it seemed somewhat smaller than its twin up in East Sheffield, at least until he drove under its flank, when once again it became clear that it was as big as a city block. There was even a square hole in the bottom of one side which looked for all the world like the entrance to a parking garage. Art drove his rover right at this hole— the Beast was moving at three kilometers a day, so it was no trick to hit it— and once inside, he drove up a curving ramp, following a short tunnel into a lock. There he spoke by radio to the Beast’s AI, and doors behind his rover slid shut, and in a minute he could simply get out of his car, and go over to an elevator door, and take an elevator up to the observation deck.

• • •

It did not take long to realize that life inside the Beast was not the essence of excitement, and after checking in with the Sheffield office, and taking a look at the ion chromatograph down in the lab, Art went back out in the rover to have a more extensive look around. This was the way things went when working the Beast, Zafir assured him; the rovers were like pilot fishes swimming around a great whale, and though the view from the observation deck was nice and high, most people ended up spending a good part of their days out driving around.