The next pictures, taken at a great distance, showed a towering wounded soldier sitting by the side of a path, his arm in a sling, the stump of one leg extended, a crude crutch on his lap. Then two wounded soldiers, both the same, standing side by side. "That's Variety One. The Wounded Soldier." Klaus reached out and took the pictures. "You see, the claws were designed to get to human beings. To find them. Each kind was better than the last. They got farther, closer, past most of our defenses, into our lines. But as long as they were merely _machines_, metal spheres with claws and horns, feelers, they could be picked off like any other object. They could be detected as lethal robots as soon as they were seen. Once we caught sight of them--" "Variety One subverted our whole north wing," Rudi said. "It was a long time before anyone caught on. Then it was too late. They came in, wounded soldiers, knocking and begging to be let in. So we let them in. And as soon as they were in they took over. We were watching out for machines...." "At that time it was thought there was only the one type," Klaus Epstein said. "No one suspected there were other types. The pictures were flashed to us. When the runner was sent to you, we knew of just one type. Variety One. The big Wounded Soldier. We thought that was all." "Your line fell to--" "To Variety Three. David and his bear. That worked even better." Klaus smiled bitterly. "Soldiers are suckers for children. We brought them in and tried to feed them. We found out the hard way what they were after. At least, those who were in the bunker." "The three of us were lucky," Rudi said. "Klaus and I were--were visiting Tasso when it happened. This is her place." He waved a big hand around. "This little cellar. We finished and climbed the ladder to start back. From the ridge we saw. There they were, all around the bunker. Fighting was still going on. David and his bear. Hundreds of them. Klaus took the pictures." Klaus tied up the photographs again. * * * * * "And it's going on all along your line?" Hendricks said. "Yes." "How about _our_ lines?" Without thinking, he touched the tab on his arm. "Can they--" "They're not bothered by your radiation tabs. It makes no difference to them, Russian, American, Pole, German. It's all the same. They're doing what they were designed to do. Carrying out the original idea. They track down life, wherever they find it." "They go by warmth," Klaus said. "That was the way you constructed them from the very start. Of course, those you designed were kept back by the radiation tabs you wear. Now they've got around that. These new varieties are lead-lined." "What's the other variety?" Hendricks asked. "The David type, the Wounded Soldier--what's the other?" "We don't know." Klaus pointed up at the wall. On the wall were two metal plates, ragged at the edges. Hendricks got up and studied them. They were bent and dented.