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twelve yards by stout buttresses.
    Considering its uselessness, it was surprisingly well put together.
    â€œI don’t really see the point of this,” I said.
    â€œThere are predators in the forest,” Linda reminded me. “Things like leopards—and scavengers, pests of one kind and another.”
    I shook my head. “As a means of keeping things out,” I pointed out, “it’s no good at all. Things which live in forests tend to be able to climb trees, and anything that could climb a tree could climb this. It’s pretty solid, but there are gaps at ground level which would easily let something the size of a rat or a snake through. It’s not a defensive wall, it marks the boundary. The boundary they decided to settle for, when it became clear to them that all their attempts to expand were doomed to failure.”
    â€œBut why were they doomed to failure? They obviously cleared a lot more land than this to start with. Why couldn’t they keep it clear?”
    That, of course, was the big question, and we were still a long, long way from a big answer. What was bugging me, right at that moment, was a much smaller question—maybe even a silly question. Why build a boundary so big and tough? It went all around the perimeter, maybe seven miles in all. How ridiculous to put the logs which went into it to such a futile use, instead of building houses, making something functional. It made no sense.
    â€œWell,” I said to Linda, “this is the first time for us. Conrad’s seen it before though not quite so bad. This is what we expected, if we expected anything.”
    Conrad had been out with the Daedalus on its first recontact mission, with Kilner. They had found five colonies engaged in a desperate struggle to survive, fighting a slow losing battle. They hadn’t been so far gone as this one—and, in fact, the visit of the Daedalus might have helped them turn the corner and start winning—but this seemed to belong to the same deadly pattern. For Linda and myself, as I’d said, it was the first time we had seen it. Floria had been an exception.
    I was hoping, just then, that time wouldn’t prove Floria to be the exception.
    â€œIt’s horrible,” she said. “Maybe I should have expected it—feared it. But there’s just no way you can be prepared.”
    I nodded my complete agreement to that.
    I gripped the top of the wooden wall and scrambled up by means of the abundant toeholds left by the curvature of the logs. I straddled the top while I helped Linda to get up beside me, then I swung round to sit on top of the structure. She did the same. Neither of us jumped down to set our feet on the soil that had been conceded to the alien world. We looked out at the sea of saplings and the clumps of bushes. Young forest, stretching away across the saddle between the hilltops, and up the distant slope. Beyond the crown of the hill we could see the real forest, in all its ancient majesty: trees a hundred feet tall even at this elevation. Down in the valleys, where the rivers ran, there would be trees like no trees which had ever grown on Earth. Vast and incredibly ancient.
    The young forest was so very young. I knew as I looked at it that this was not the true Dendra but a pale shadow.
    Forests, however, are very patient.
    The untidy stand of saplings, with their woefully inadequate crowns of thin branches and slender leaves, lacked the dignity of age, but was full of life. There was a constant flurry of movement within the bushes as crowds of small birds hopped and fluttered from branch to branch. There seemed to be a great number of butterflies and other winged insects.
    It didn’t seem strange to me, as I perched on top of the wall, that the butterflies stayed outside, in Dendran territory, as did most of the birds and many of the other flying things. I sat at the junction of two worlds—different worlds. It was natural that each