I threw up my gun impulsively and fired. By now I had gotten the feel of the weapon, and my aim was good. I hit him. The "bullet" must have penetrated his body and exploded. For one moment I saw him flying through the air. Then the explosion, and he had vanished. He never finished his leap. It was annihilation. How many more of them there were I don't know. But this must have been too much for them. They used a final round of shells on us, all of which exploded harmlessly, and shortly after I heard them swishing and crashing away from us through the tree tops. Not one of them descended to earth. Now I had time to give some attention to my companion. She was, I found, a girl, and not a boy. Despite her bulky appearance, due to the peculiar belt strapped around her body high up under the arms, she was very slender, and very pretty. There was a stream not far away, from which I brought water and bathed her face and wound. Apparently the mystery of these long leaps, the monkey-like ability to jump from bough to bough, and of the bodies that floated gently down instead of falling, lay in the belt. The thing was some sort of anti-gravity belt that almost balanced the weight of the wearer, thereby tremendously multiplying the propulsive power of the leg muscles, and the lifting power of the arms. When the girl came to, she regarded me as curiously as I did her, and promptly began to quiz me. Her accent and intonation puzzled me a lot, but nevertheless we were able to understand each other fairly well, except for certain words and phrases. I explained what had happened while she lay unconscious, and she thanked me simply for saving her life. "You are a strange exchange," she said, eying my clothing quizzically. Evidently she found it mirth provoking by contrast with her own neatly efficient garb. "Don't you understand what I mean by 'exchange?' I mean ah--let me see--a stranger, somebody from some other gang. What gang do you belong to?" (She pronounced it "gan," with only a suspicion of a nasal sound.) I laughed. "I'm not a gangster," I said. But she evidently did not understand this word. "I don't belong to any gang," I explained, "and never did. Does everybody belong to a gang nowadays?" "Naturally," she said, frowning. "If you don't belong to a gang, where and how do you live? Why have you not found and joined a gang? How do you eat? Where do you get your clothing?" "I've been eating wild game for the past two weeks," I explained, "and this clothing I--er--ah--." I paused, wondering how I could explain that it must be many hundred years old. In the end I saw I would have to tell my story as well as I could, piecing it together with my assumptions as to what had happened. She listened patiently; incredulously at first, but with more confidence as I went on. When I had finished, she sat thinking for a long time. "That's hard to believe," she said, "but I believe it." She looked me over with frank interest.