When he got to the hole, his arrangement of tin cans, traps, and tobacco juice no longer looked nearly as secure as it had. He got his ax and cut two stout posts, framing the hole; built a stout slab door and hung it from them. Then he drove stakes close together at the threshold, to foil any attempts to dig under, and trimmed a sill tight to the door. His feeling in this matter, as it happened, was sound. The Harn was beginning to develop a pretty strong dislike for Ed Brown. Three of its stinging units were dead, and most of the rest were in poor shape, thanks to the tobacco spray. It had got a little whiff of the stuff itself, not enough to do any serious damage ordinarily, but right now, so close to swarming time-- Ed was going to have to go. So far, in this world, the Harn had needed only the three basic types of mobile units. There were other standard types, however, for dealing with more complicated situations. As it happened, a couple of carrier embryos were at just about the right stage. With a little forcing, they could be brought on in not too long a time. Meanwhile, the Harn would do what it could with the material available. When Ed came through the next day to set his snares, the Harn was prepared to test his snakeproof pants. They held, which was disconcerting to the Harn, but it was a hard creature to convince, once thoroughly aroused. Ed was not too sure of how well the pants would stand up to persistent assault himself. After the third ambush, he took to spraying suspicious looking spots with tobacco juice. He shot two more stingers in this way, but it slowed him up quite a bit. It took him all day to make four sets. In the next three days he made a dozen sets and caught two carriers. Then, the fourth day, as he adjusted a snare, a seeming root suddenly came to life and slashed at his hand. He was wearing gloves to keep his scent from the snares, and the fang caught the glove and just grazed the ball of his left thumb. The hatchet he had been using to cut a toggle was lying by his knee. He snatched it up and chopped the stinger before it could strike again, then yanked off the glove and looked at his hand. A thin scratch, beaded with drops of blood, showed on the flesh. Unhesitatingly, he drew the razor edge of the hatchet across it, sucked and spat, sucked and spat again and again. Then he started for home. He barely made it. By the time he got to the hole, he was a very sick man. He latched the door, stumbled into the cabin and fell on the bed. It was several days before he was able to be about again, his hand still partly paralyzed. During that time, the situation changed. The Harn took the offensive.