Rigg saw the stream before any of the others.
Loaf was an experienced soldier; Olivenko not so experienced, but not untrained, either; and Umbo had grown up in the village of Fall Ford, which was almost like living in the woods.
But only Rigg had tramped the high forests above the Upsheer Cliffs, trapping animals for their fur while the man he called Father taught him more than Rigg ever thought he would need to know. Rigg practically smelled water like an animal. Even before they crested the low grassy rise he knew that there would be a stream in the next crease between hills. He even knew it would be only a rill, with no trees; the ground here was too stony.
Rigg broke into a jog.
"Stop," said the expendable they were calling Vadesh.
Rigg slowed. "Why? That's water, and I'm thirsty."
"We're thirsty," said Umbo.
"You cannot drink there," said the expendable.
"Cannot? There's some kind of danger?" asked Rigg.
"Or a law," suggested Olivenko.
"You said you were leading us to water," said Loaf, "and there it is."
"That's not the water I'm taking you to," said Vadesh.
Only now did Rigg realize what he wasn't seeing. It was his inborn gift that all the paths of the past were visible to him. Humans and animals all left traces behind them, paths in time. If they ever traveled through a particular place, Rigg could tell where they had gone. It was not something he saw with his eyes--his eyes could be closed or covered, or there could be walls or solid rock between him and a path, and he would still know where it was, and could figure out what kind of creature made it, and how long ago.
There had been no human traffic at this stream in ten thousand years. More tellingly, few animals had come there, and no large ones.
"It's poisonous," said Rigg.
"Is that a guess?" asked his sister, Param, "or do you know somehow?"
"Even animals don't come here to drink," said Rigg. "And no human for a long time."
"How long?" asked Vadesh.
"Don't you know?" asked Rigg.
"I'm curious about what you know," said Vadesh. "I have not known a human who can do what you can do."
"Nearly as long as since the beginning of human settlement on this world." Rigg had a very clear idea of what paths that old were like, since he had just crossed through the Wall between his home wallfold and this one, by clinging to an animal that, in the original stream of time, had died in the holocaust of humans' first coming to the planet Garden.
"That is off by only a little less than a thousand years," said Vadesh.
"I said ‘nearly,'" answered Rigg.
"A thousand years this way or that," said Param. "Close enough."
Rigg still didn't know Param well enough to tell if her sarcasm was friendly teasing or open scorn. "What kind of poison?" he asked Vadesh.
"A parasite," said Vadesh. "It can live out its entire lifecycle in the stream feeding off the bodies of its siblings, ancestors, and descendants, until one of them eats it. But if a larger animal comes to drink, it attaches to the face and immediately sends tendrils into the brain."
"It eats brains?" asked Umbo, intrigued.
"No," said Vadesh. "It infiltrates them. It echoes the neural network. It takes over and controls the host's behavior."
"Why in the world would our ancestors bring along such a creature when they came from Earth?" asked Umbo.
"They didn't," said Olivenko.
"How do you know that?" asked Loaf. His tone showed he was still skeptical of Olivenko, who was only a member of the city guard in Aressa Sessamo, rather than a real soldier.
"Because if they had, it would exist in every wallfold," said Olivenko, "and it doesn't exist in ours."
Olivenko thinks the way Father taught me, thought Rigg. Don't assume: Think it through.
Vadesh was nodding. "A very tough little creature, the facemask."
"What the humans of this wallfold named it. For reasons that would have become tragically obvious if you had bent over to drink from the stream."
Something didn't ring true about this. "How can a creature that evolved on Garden successfully take over the brains of creatures from Earth?" asked Rigg.
"I didn't say it was successful," said Vadesh. "And you are now as close as is safe. To avoid picking up facemasks from the wet ground beside the stream--they can attach to any skin and migrate up your body--you should follow in my footsteps exactly."
They followed him in single file through the grass, with Rigg bringing up the rear. The path Vadesh took them on was the highest ground. Each time they reached a damp patch they jumped over it. The rill was narrow here. No one had trouble overleaping it.
Only when they got to higher ground several rods beyond the rill was Rigg able to continue the conversation. "If the parasite wasn't successful, why is it still alive here?"
"The parasite is successful in attaching to humans and Earthborn beasts of all kinds," said Vadesh. "But that's not really how we measure success in a parasite. If the parasite kills its host too quickly, for instance, before the parasite can spread to new hosts, then it has failed. The goal of a parasite is like that of any other life form--to survive and reproduce."
"So these facemasks kill too quickly?" asked Umbo, shuddering.
"Not at all," said Vadesh. "I said ‘for instance.'" He smiled at Rigg, because they both knew he was echoing Rigg's earlier testy reply when Vadesh told him his time estimate was off by a millennium.
"So in what way did this parasite fail?" asked Rigg--the way he would have pushed Father, an attitude that came easily to him, since not just in face and voice but in evasiveness, smugness, and assumption of authority this expendable was identical to the one that had taken Rigg as an infant from the royal house and raised him.
"I think that with native species," said Vadesh, "the parasite rode them lightly. Cooperating with them. Perhaps even helping them survive."
"But not with humans?"
"The only part of the earthborn brain it could control was the wild, competitive beast, bent on reproduction at any cost."
"That sounds like soldiers on leave," said Loaf.
"Or academics," said Olivenko.
Vadesh said nothing.
"It sounds like chaos," said Rigg. "You were there from the beginning, weren't you, Vadesh? How long did it take people to learn of the danger?"
"It took some time for the facemasks to emerge from their chrysalises after the disaster of the human landing," said Vadesh. "And still longer for the people of Vadeshfold to discover that facemasks could infest humans as well as cattle and sheep."
"The herders never got infected?" asked Loaf.
"It took time for a strain of facemasks to develop that could thrive on the human body. So at first it was like a pesky fungal infection."
"And then it wasn't," said Rigg. "Facemasks are that adaptable?"
"It's not blind adaptation," said Vadesh. "They're a clever, fascinating little creature, not exactly intelligent, but not completely stupid, either."
For the first time, it occurred to Rigg that Vadesh was not just fascinated by the facemasks, but enamored of them.
"They can only attach to their host in the water," said Vadesh, answering a question no one had asked. "And once they attach to an air-breather, they lose the ability to breathe in water. They only get their oxygen from the blood. You know what oxygen is?"
"The breathable part of air," said Umbo impatiently. Olivenko chuckled. Of course, thought Rigg--Olivenko was a scholar, and Umbo had studied for a time with Rigg's father.
But Rigg noticed that Loaf and Param seemed to have no idea what Vadesh meant. How could air be divided in parts? Rigg remembered asking Father exactly that question. But there was no point in explaining the point now or soon or, probably, ever. Why would a soldier-turned-innkeeper and a royal heiress who had fled her throne require a knowledge of the elements, of the behavior of gases and fluids?
Then again, Rigg had thought, all through his years of education, tramping with Father through the woods, that he would never need anything Father taught him except how to trap, dress, and skin their prey. Only when Father's death sent Rigg out in the world did he learn why Father had trained him in languages, economics, finance, law, and so many other subjects, all of which had proven vital to his survival.
So Rigg started to explain that invisible air was really made of tiny particles of several different types. Loaf looked skeptical and Param bored, and Rigg decided that their education wasn't his job.
He fell silent and thought about parasites that could only attach to humans in water, and then they lost the ability to breathe on their own. Rigg filed the information away in his mind, the way Father had taught him to do with all seemingly useless information, so he could recall it whenever Father decided to test him.
I've been on my own for a year, thought Rigg, and still in my thoughts he's always there, my pretended father, my kidnapper for all I know. He's the puppeteer who, even dead, is pulling all the strings inside my mind.
Lost in such thoughts, Rigg did not notice the first building that came in sight. It was Loaf, ever alert as a soldier should be, who saw the glint of metal. "It's like the Tower of O," he said.
It was indeed, in that it was tall and of a similar substance. But it did not rise to a point and was not rounded like a cylinder. And there were several of them nearby, and none of them was half so tall as the Tower of O.
But they were impressive nonetheless, and tall enough that it took two more hours of walking after they first saw them for their little group to come close enough to see that these towers were made from the same material, and formed the skyline of a city.
"How could they build with this . . . substance?" asked Loaf. "People have tried to cut into the Tower of O many times over the years, and neither tool nor fire can affect it."
"Who would try to damage it?" asked Umbo.
"Conquerors who want to show their power," said Olivenko. "Rigg's and Param's people arose only lately. The Tower has been there ten thousand years."
The talk of duration made Rigg realize something he should have noticed at once, as soon as they knew it was a city they were coming to. There were human paths again, as there had not been near the stream, but all of them were old. None more recent than ten thousand years.
"How long has this city been abandoned?" asked Rigg.
"It isn't abandoned," said Vadesh.
"There hasn't been a human being here for a long time," said Rigg.
"But I've been here," said Vadesh.
You're not a human being, Rigg wanted to say. You're a machine; you leave no path. A place that contains only you is uninhabited. But it seemed too rude to say aloud. Rigg saw the absurdity of his attitude: If he truly thought of Vadesh as only a machine, rudeness would not be an issue.
"Where did the people go?" asked Param.
"People come and go in the world, and where there once were cities there are only ruins, and where once there was nothing, cities rise," said Vadesh.
Rigg noticed how nonresponsive Vadesh's answer was, but did not challenge him. Rigg trusted Vadesh too little to want him to know he wasn't trusted.
"And there's water here?" asked Loaf. "Because my need for it is getting pretty urgent."
"I thought you field soldiers drank your own piss," said Olivenko.
"We do pee into canteens," said Loaf. "But only so we can bring it back for the officers of the city guard to drink."
It could have been a quarrel, but to Rigg's relief, Olivenko just smiled and Umbo laughed and it went nowhere. Why did they still irritate each other so much, after all they had been through together? When would rivals become comrades?
So all the people of this city were gone. Rigg began to scan for the paths that would show a great migration out of the city, but before he could make much progress, Vadesh led them into a low building of ordinary stone, which showed its many centuries of weathering.
"Did someone live here?" asked Umbo.
"It's a factory," said Vadesh.
"Where did all the people sit to work?" asked Olivenko.
"A mechanical factory," said Vadesh. "And most of it is underground. I still use it, when I need any of the things the factory makes. But they needed safe water for the supervisors and mechanics, and for the people who hauled things in and hauled things out." He led them through a doorway into a dark chamber. As they passed through the door after him, a bright light came from above. The whole ceiling was aglow, very much like the lights inside the Tower of O.
The others gasped in awe, but Rigg was noticing that the paths of humans into this chamber were few and ancient. This building had only been used for a few decades at the most. It had been abandoned by the same generation of people who had built it.
Vadesh touched the front of a thick stone pillar and at once they heard the sound of running water inside the pillar. Then he touched another place, and a portion of the pillar came away in his hand. It was a stone vessel halfway between a drinking mug and a waterbucket in size. He handed it to Loaf. "Because your need was so urgent," said Vadesh.
"Is it safe?" asked Rigg.
"It's filtered through stone. No parasites of any kind can possibly get into this water."
Again, Rigg noticed that while Vadesh answered, he only answered about the likelihood of parasite infestation, not the actual question Rigg had asked.
Loaf handed the water to Param without tasting it. "You need this most," he said.
"Because I'm a frail princess?" Param asked with a hint of resentment.
Well, she was physically frail and she was a princess. Until their mother tried to kill her and Rigg, she was assumed to be heir to the Tent of Light. Years of living in the narrow bounds of captivity had made her physically weak, and the journey to the Wall had only improved her stamina by a little. But no one was rude enough to point this out to her.
"You need it most because you and Umbo lived on your water for an extra week that we didn't live through," said Loaf.
Param took the water and drank. "It's perfect," she said. "It tastes fresh, and nothing else. Except a tinge of something . . ."
"Trace metals," said Vadesh. "From the rock it filtered through."
Umbo drank next. He tried to pass it to Rigg, but Rigg would not take any until Loaf and Olivenko had also drunk.
"There's plenty," said Vadesh.
"Then finish it, Loaf," said Rigg. "I'll drink from the second serving."
"He thinks I spit in it," said Umbo.
"Didn't you?" said Loaf. "You usually do." Then Loaf drank it off. "Delicious," he said, as he handed the empty vessel to Vadesh for refilling.
Rigg did not know why he did not trust Vadesh. This expendable had no mannerisms that were not identical to those of Rigg's father. Perhaps that was the cause of his suspicions. But he was sure that Vadesh was deceptive and dangerous, not because he deflected questions and clearly had his own agenda--those were Father's constant attributes as well--but because of which questions he wouldn't answer.
Father would have told me why the people were gone from this place. It would have been the first thing he explained, because telling me why people do the things they do was always his favorite topic.
Vadesh isn't educating me, that's why he doesn't explain it.
But Rigg did not believe his own excuse. As Father had taught him, he did not believe the first explanation his mind leapt to. "It will often be right, and as you get more experience of life it will usually be right. But it will never be reliably right, and you must always think of other possible explanations or, if you can't, then at least keep your mind open so you will recognize a better explanation if one emerges."
So Rigg did not trust Vadesh. Moreover, he was sure that Vadesh knew that Rigg did not trust him--because Father would have known.
When Rigg got his water from the second cupful, it was as delicious as the others said.
He poured the last water from his canteen onto the floor and then moved to put it into the space the stone vessel came from.
"No," said Vadesh. "One reason this water can be trusted is that it is never used to fill any container but this one. It won't work anyway. It only pours out water when this is in place." Vadesh reinserted the stone cup, and again the water could be heard gushing into the stone.
They all emptied their canteens of the stale traveling water they obtained when they last filled at a stream two days before, then refilled them from the stone vessel. With enemies pursuing them, they had not dared to stop even for water on that last day before they crossed the Wall.
"It's getting near dark outside," said Loaf. "Is there a safe place to sleep in this city?"
"Everywhere here is safe," said Vadesh.
Rigg nodded. "No large animals ever come here," he said.
"Then is there a comfortable place here?" asked Umbo. "I've slept on hard floors and on grass and pine needles, and unless there's a bed . . ."
"I don't need beds," said Vadesh, "and I didn't expect company."
"You mean they didn't make their beds out of stuff that never decays?" asked Olivenko.
"There is nothing that doesn't decay," said Vadesh. "Some things decay more slowly than others, that's all."
"And how slowly do you decay?" asked Rigg.
"Slower than beds," said Vadesh, "but faster than fieldsteel."
"And yet you seem as good as new," said Rigg. "That's a question."
Vadesh stood by the water pillar gazing at him for a long moment. Deciding, Rigg supposed, how to respond without telling him anything useful.
"My parts are all replaceable," he said. "And my knowledge is fully copied in the library in the Unchanging Star."
"Who makes your new parts?" asked Rigg.
"I do," said Vadesh.
"Here?" asked Rigg. "In this factory?"
"Some of the parts, yes," said Vadesh.
"And the other parts?"
"Somewhere else, obviously," said Vadesh. "Why do you ask? Do you think any of my parts are defective?"
Now, that was interesting, thought Rigg. I was going to ask him if he ever had enough parts to make a complete new copy of himself, but he assumed I was doubting that he was functioning perfectly.
This made Rigg assume that Vadesh himself had doubts about his functionality.
"How could I know if a machine so perfect that I could live with one for thirteen years without realizing it wasn't human is not up to par?" he asked.
"Exactly," said Vadesh, as if they had been arguing and Vadesh had just proved his point.
And maybe we were arguing, thought Rigg. And whatever Vadesh might have done since I met him, he certainly did not prove anything. All he did was make me wonder if he's broken somehow. Did he do that for a purpose? Is it an illusion, so I will underestimate his ability? Or is it a symptom of his imperfection, that he could raise doubts in my mind when his goal was to reassure me?
"Thanks for the water," said Rigg. "I think we'll go out of the city to sleep on softer ground. Unless there's a couple of you who want to sleep on stone."
There were no volunteers. Rigg led the way out of the building, following their own paths back out of the empty city. At first Vadesh seemed to assume he was welcome to come with them, but Rigg disabused him of that notion. "I don't believe you sleep," Rigg said to him. "And we won't need you to find us a resting place."
Vadesh took the hint and returned into the factory--leaving no trace of himself for Rigg to follow. Just like Father, Vadesh was pathless; only living beings made paths through time. Machines might move about, but they left no track visible to Rigg's timesense.
It would have been so useful to trace Vadesh's movements through these buildings over the past ten thousand years, since all the people left. And perhaps even more interesting to trace his movements for the thousand years before that, when the people were still here. What was he doing when they left? Why did he still come here, if all the people were somewhere else?