2312

Then the tunnel ahead of them appeared to end. They had all put their helmets back on, as it was the easiest way to carry them, and now they shone their helmets’ headlamps into the darkness before them. A mass of rock rubble filled the tunnel, floor to roof. It was cold here, and suddenly Swan said, “We’d better seal our helmets,” and her faceplate slid down. Wahram did the same.

They stood there looking at the blockage.

“All right,” Swan said grimly. “Can’t go west. We’ll have to go east, I guess.”

“But how long will that take?” Wahram said.

She shrugged. “If we sit here, it will be eighty-eight days till sunset. If we walk, it will be less.”

“Walk around half of Mercury?”

“Less than half, because we will be walking and the planet will be rolling. That’s the point. I mean, what else are we going to do? I’m not going to sit here for three months!” She was almost in tears, he saw.

“How far is it again?” he asked, thinking half of Titan as he said it. His stomach contracted within him.

“About two thousand kilometers. But if we walk east at, say, thirty kilometers a day, we shorten the wait time to something more like forty days. So we can cut it in half. That seems worth it to me. And it doesn’t have to be continuous walking. I mean, it’s not like the sunwalkers. We walk a day’s worth, eat, sleep a night, then walk again. Set a daily schedule. If we hiked for twelve hours out of every twenty-four, that would be a lot, but it would save even more days. What, Pauline?”

“Can you turn up Pauline’s voice again?” Wahram requested.

“I don’t want to now. She says twelve-hour days of walking would shorter our time down here by around forty-five days. That’s enough for me.”

“Well,” Wahram said. “That’s a lot of walking.”

“I know, but what are you going to do? Sit here for over twice as long?”

“No,” he said slowly. “I guess not.”

Although really it would not be so very long. A rereading of Proust and O’Brian, a few times through the Ring cycle; his little wristpad was very well stocked. But the way she stood there looking at him, these were not thoughts he felt comfortable expressing.

“I’ll turn up Pauline,” she said, as if giving him something in exchange for his agreement.

“ Solvitur ambulando,” Pauline said. “Latin for ‘It is solved by walking.’ Diogenes of Sinope.”

“Thus you prove motion is real,” Wahram supposed.

“Yes.”

Wahram sighed. “I was already convinced.”

B ack at the first underground station they took stock. The three sunwalkers were perfectly happy to walk for six or seven weeks; it was very like their usual mode of existence. Their names were Tron, Tor, and Nar. They were gender nondescripts as far as Wahram was concerned, and seemed to him very young and simple. They lived only to hike around Mercury; they seemed to know nothing more than that, or perhaps they didn’t speak much to strangers. But what they did say seemed childlike to him, or provincial in the extreme. There were whole terraria filled with such folk, of course, but he had gotten used to thinking of the Mercurials as highly sophisticated, steeped in history and art and culture. Now he was learning that it was not universally true. He realized he had thought sun worshippers would be followers of the various early solar religions of ancient Egypt, Persia, the Inca-but no. They just liked the sun.

It looked like they were going to have to spend a couple of nights sleeping on the floor of the unimproved tunnel in between each way station. “Every third day,” Swan said, “we can resupply. It sets a good goal.”

“We might even be able to go farther,” Tron said shyly.

Tron was the one with the broken arm, so Wahram refrained from mentioning that for him personally, thirty-three kilometers a day might prove enough, or too much. That he might be the drag on this group was discouraging. In any case Swan was overseeing the filling of backpacks she had found in the emergency supply cabinets: their spacesuit helmets, some emergency air, water bottles, food, air mattresses, a little pot and stove. A roll of aerogel blankets, not very warm-looking, but the utilidor would stay at this temperature, Swan said; and it was pretty warm.