Leitz played with the keyboard for a few moments, and the viewpoint shifted to a more intimate and slow-moving aerial view of hilly terrain.

To Matthew, who had seen the Andes and the Himalayas at close range, this seemed a fairly poor example of a mountain range, not so much because of its lack of elevation as the relatively gentle contours of its individual elements. There was a big river meandering through the lowlands, which the viewpoint followed from the edge of the grassy plain towards its distant source.

A couple of minutes went by before they saw the bubble-domes comprising the Base. It wasn’t too hard to understand why the nearby ruins hadn’t been easy to pick out from directly above, given that the treelike forms had taken it over so completely. Now that there were extensive patches of cleared ground and paths running between them it was easy to see the stark outlines of artificial structures, but it was impossible to tell how extensive the ruins were.

“You can just about see the outlines of the fortifications in the undulations of the overgrowth,” Leitz said, pointing.

At first, because they followed the contours of the hillsides and because there were so many of them, Matthew thought that the “fortifications” to which Leitz was referring must really be terraces from which some or all of the enclosed soil had been leached by centuries of rainfall. But when he was able to compare cleared sections of the walls with the buildings at the core of the vast complex, the proportions suggested that they really mighthave been fortifications. Against what adversaries, he wondered, could a maze like that have been erected? What kind of enemy could have made such lunatic industry conceivable, let alone necessary?

Close-ups showed various sections of wall in much greater detail, including two into which pictures had been carved. The pictures were primitive and cartoonish, but Matthew drew in his breath sharply as he realized that the bipedal stick figures could have passed for a child’s representation of human beings. Apart from the humanoid figures the sketches also showed arrays of bulbous entities, vaguely reminiscent of obese corncobs, and much bigger structures, triangular in silhouette, that might have been conical or pyramidal.

“They’re people!” Solari exclaimed.

“They appear to have been humanoid,” Leitz admitted.

“So what killed them off?” the policeman wanted to know.

“That’s one of the things the people at Base Three are trying to find out,” Leitz said. “It isn’t easy, because their specialisms are only peripherally related to the job. The Chosen People didn’t include any archaeologists—the nearest thing we could find when we thawed out personnel to make up the second half of the team was an anthropologist.”

“Why are you so sure they’re extinct?” Matthew asked. “If your flying eyes can’t get information back from ground level, the whole continent must qualify as terra incognita. The fact that the city-dwellers abandoned the site doesn’t mean that their cousins aren’t still around.”

“We’ve done what we can to find them,” the young man assured him. “Agricultural activity should be easy enough to detect, even at a far more restricted level, and even hunter-gatherers need fires. If anyone had lit a single cooking fire in the last three years, anywhere on the world’s surface, we’d have been able to home in on it. If they were alive somewhere out in the long grass, invisible from the air, they’d have to have gone back to the very beginning, eating what they hunt and gather in its raw state. That seems unlikely. Incredible, even. The people on the ground who believe that the aliens are still around have their own reasons for wanting to believe it.”

“The human race had some pretty narrow squeaks,” Matthew said, pensively. “There used to be more genetic variation in a single chimpanzee troop than in the entire human race, before chimps became extinct. Mitochondrial Eve had lived not much more than a hundred and forty thousand years before Hope’s odyssey began. Animals as big as humans are more vulnerable to catastrophes of all kinds than their smaller and humbler cousins. If these guys had never domesticated fire, they’d be even more vulnerable than our ancestors. Still …”

“Which side was Delgado on?” Solari asked Frans Leitz. “On the extinction question, I mean.”

“I don’t know—but he was enthusiastic about building the boat.”

“What boat?” Solari asked.

“I think it was Dr. Gherardesca’s idea. She’s the anthropologist. She figured that if it wasn’t possible to recover data about ground-level activity in the grasslands from flying eyes, the best way to do it would be to take a boat downriver. It was just about ready when Professor Delgado was killed, although they’d asked for one last consignment of equipment—we’re holding that so that we can send you down with it.”

“How many other people were working at Base Three along with Delgado?” Solari persisted.

“Seven.”

“Seven!” Matthew could hardly believe it. “You found a ruined city made by intelligent humanoids, and you sent sevenpeople to investigate it! The biggest news story in history, and sevenpeople is all you can spare to follow it up.”

“There wereeight,” Leitz pointed out, blushing grayly yet again as his discomfort increased by an order of magnitude. “And will be again, once you’re there.” He was already turning away to resume his interrupted retreat. “I really must go now. You’ll soon get the hang of the keypads if you keep playing with them. There’s plenty more library material. Someone will pick you up when it’s time for you to see Captain Milyukov.”

SIX

Vince Solari waited until the young man had left the room before saying: “Milyukov? Wasn’t the original captain called Ying?”

“That was seven hundred years ago,” Matthew pointed out. “ Captainisn’t a hereditary title. A ship’s crew has to be run on strictly meritocratic principles—supposedly.”

“Why supposedly?” Solari had relaxed, allowing the keyboard to hang loosely from his tired hand. The image on the screen had frozen while displaying the internally lit bubble-domes of Base Three, strangely forlorn in a gathering evening that was turning everything purple to matt black.

“Seven hundred years is a long time,” Matthew said, “and the ship was always capable of running itself between big decisions. Five or six lifetimes, maybe as many as twenty generations, can produce considerable social and political changes, and meritocracies always have a habit of backsliding.”

Solari nodded, slowly. “I see,” he said. “There’s another factor that needs consideration too. Most of the Chosen—including you, I guess—were frozen down before the new generation of plagues had begun to do their worst. Interplanetary distances weren’t quarantine enough to keep the chiasmalytic transformers and their vicious kin on Earth. At least some of the crew must have been sterilized before Hopeleft the system. They must have been forced to adopt whatever countermeasures allowed the reconstruction of Earthly society.”

“How bad did things get before you left?” Matthew asked, quietly.

“I was frozen down twenty-four years after you,” Solari reminded him. “The chiasmalytic transformers were running riot. Nobody had given up hope of finding a cure, but they were stripping the eggs out of the ovaries of aborted fetuses and little girls, and splitting viable embryos so that they could keep the clones as spares … all kinds of weird stuff. And every week seemed to bring news of some new breakthrough in longevity technology that mightbeat the Miller Effect, and mightput us all on the escalator to emortality, and mightmake it possible for civilization to go on forever even if no one ever had another baby for as long as the ecosphere lasted. Not that it made a jot of difference to the doomsayers and the defeatists, the neohysterics or the hyperhedonists. You missed some crazy times, Matt. Times that only a prophet could have relished. I remember seeing you on TV, you know, when I was a kid. Couldn’t really miss you, until you dropped out of sight.”