“The symmetry of the continents is a little weird,” Leitz put in, obviously feeling some slight obligation to substitute for the missing commentary. “The polar island-continents are so similar in size and shape that some of the first observers thought that the planet had been landscaped by continental engineers. The star is nearly a billion years older than the sun, so evolution has had a lot longer to work here than it had on Earth, but Professor Lityansky reckons that the relative lack of axial tilt and tidal drag haven’t added sufficient agitation to the surface conditions to move evolution along at a similar pace. He reckons that Earth was unusually lucky in that respect, and that’s why we seem to be the first starfaring intelligences in this part of the galaxy. The surface isn’t very active, volcanically speaking, and the climatic regimes are stable. The weather’s fairly predictable in all latitudes, although it varies quite sharply from one part of the pattern to another.”

The viewpoint was zooming in now, as if free-falling from orbit, then curving gracefully into a horizontal course a thousand meters or so above the surface.

The sky was bluish, but it had a distinct violet tinge, like an eerie echo of the vegetation.

At first, Matthew thought that the grassy plain over which the AI-eye was soaring wasn’t so very different from an Earthly prairie. The lack of any comparative yardstick made it difficult to adjust the supposition, but when Leitz told him that the stalks bearing the complex crowns were between ten and twenty meters tall he tried to get things into a clearer perspective.

“The rigid parts of the plants aren’t like wood at all,” Leitz said. “More like glass. Professor Lityansky will explain the biochemistry.”

There were very few tree-like forms on the plain, but when the point of view soared higher in order to pass over a mountain range, Matthew saw whole forests of structures that seemed to have as much in common with corals as with oaks or pines. They seemed to him to be the kind of trees that a nineteenth-century engineer—a steam-and-steel man—might have devised to suit a landscape whose primary features were mills and railroads: trees compounded out of pipes and wire, scaffolding and stamped plate. Given what Leitz had said about the structures being vitreous rather than metallic, the impression had to be reckoned illusory, but it still made the forests and “grasslands” seem radically un-Earthlike. If this world really could be counted as an Earth-clone, Matthew thought, it was a twin whose circumstances and experience had made a vast difference to its natural heritage.

When the low-flying camera eye finally reached the shore of a sea Matthew saw that its surface layer was indeed covered with a richer floating ecosystem than he had ever seen on any of Earth’s waters. The inshore waters were dappled with huge rafts of loosely tangled weed, and the seemingly calm deeper waters were mottled with vast gellike masses. Matthew did not suppose for an instant that they really were amoebas five or fifty miles across, but that was the first impression they made on his mind. He tried to think in terms of leviathan jellyfish, gargantuan slime-molds, oceanic lava lamps or unusually glutinous oil slicks, but it didn’t help. There was nothing in his catalog of Earthly appearances that could give him a better imaginative grip on what he was looking at.

It was difficult to make out much detail from the present height of the viewpoint, but that disadvantage was compensated by the sheer amount of territory that was covered. Matthew was able to see the black canyons splitting the polar ice caps, and the shifting dunes of the silvery deserts. He saw islands rising out of the sea like purple pincushions and he saw mountains rising out of the land like folds in a crumpled duvet.

The mountains had no craters; they did not seem to be the relics of volcanoes. Perhaps, Matthew mused, the continents of the New World had been as richly dotted with extinct and active volcanoes as the continents of Earth a billion years ago, but a billion years was a long time, even in the lifetime of a world. Perhaps, on the other hand, the New World had been just as different then, or even more different. If it qualified as an Earth-clone at all, it was because its atmosphere had much the same precious mix of gases as Earth’s, calculated to sustain a similar carbon-hydrogen-nitrogen biochemistry, not because it was actually Gaea’s twin sister. Perhaps Earth-clonewas entirely the wrong word, applied too hastily and too ambitiously because truer clones had proved so very hard to find—but Matthew reminded himself of what he had told Leitz. He would be better able to make up his mind when he knew all the facts.

The viewpoint became even more intimate, picking out a strange collection of objects that looked like a huge, white diamond solitaire set amid a surrounding encrustation of tinier gems. The whole ensemble was situated on a low-lying island some twenty or twenty-five kilometers from one of the major continental masses.

“Base One,” Leitz told them. “The soil inside the big dome was sterilized to a depth of six meters and reseeded with Earthly life, but there are dozens of experimental plots mixing the produce of the two ecospheres in the satellite domes.”

“Is that where Delgado was killed?” Solari wanted to know.

“Oh, no—he was at Base Three, in the mountains of the broadleaf spur of Continent B.”

“Continent B?” Matthew echoed. “You can’t agree on a name for the world, you’re numbering your bases and you’re calling its continents after letters of the alphabet? No wonder you don’t feel at home here.”

Leitz didn’t react verbally to his use of the word you, but the gaze of his green eyes seemed to withdraw slightly as he retorted: “It’s not the crew’s place to name the world or any of its features, and it’s not the crew’s fault that the colonists are so reluctant.”

But it was the crew who selected and surveyed this world, and decided to call it an Earth-clone, Matthew said to himself. If the colonists have discovered that they’ve bitten off more than they can chew, why shouldn’t they blame the people who woke them up with reckless promises? But why would the crew jump the gun? Why would they decide that the world was ripe for colonization if it wasn’t? He didn’t voice the questions, because maturing suspicions had made him wary and because an appointment had now been set for him to see the captain—the man with all the answers. He would be in a better position to listen and understand when his body had caught up with his brain and he was a little less tired.

“How big is Base Three, compared with Base One?” Solari asked, still clinging to his own tight focus on practical matters.

“Tiny,” Leitz told him. “Only a couple of satellite domes. It wasn’t part of the original plan—Base Two is in the mountain-spine of Continent A, only a few hundred kilometers from Base One, and there was no plan to establish a third base so far away from the first—but when the surveyor’s eyes spotted the ruins the groundlings had to improvise. They’re establishing supply dumps and airstrips in order to create a proper link, but it was very difficult to transport the first party, and we had to top up the personnel with a new drop.”

“Why did it take so long to find the ruins?” Matthew asked.

“The overgrowing vegetation obscured what’s left of the dwellings and broke up the lines of the fortifications. We had trouble surveying Continent B because it’s very difficult to get signals back from ground level. Flying eyes are too small to carry powerful transmitters, and the crowns of the giant grasses and trees block them out. Standard beltphones aren’t much better, so anyone calling from Base Three or its surrounds has to be sure to stand in the open.”

“Can we get a picture of Base Three?” Solari interrupted.