The cramping darkness was suddenly full of threats. In panicky haste he continued his feeling-out of the walls, found that he was in a small domed chamber, high enough in the center so that he could almost stand upright. On three sides the walls extended down to the uneven floor, or to the mouths of horizontal crevices too narrow to stick more than an arm in. On the fourth side was a low opening. By getting down on hands and knees he could wriggle in. It led slightly upward. The smell of woodsmoke grew heavier. After two sharp turns, where jagged edges caught but did not tear his heavy clothing, he began to see the gray gleam of daylight. The roof of the passageway grew higher, so that he could almost walk upright. Then it suddenly opened into a larger chamber, the other end of which was completely open to a gloomy landscape. This landscape consisted of a steep hillside of granite boulders and wind-warped pines, all patched with snow, at a middle distance, as if across a ravine. But Thorn did not inspect it closely, for he was looking chiefly at the fire blocking the mouth of the narrow passageway, sending up smoke that billowed back from the ceiling, making the day even more gloomy and dim. It immediately struck him as being a very remarkable fire, though he couldn't say why. After a while he decided that it was because it had been very cleverly constructed to burn steadily for a long time, some of the logs and branches being so placed that they would not fall into the fire until others had been consumed. Whoever had built that fire must have painstakingly visualized just how it was going to burn over a period of several hours. But why should he waste time admiring a fire? He kicked it aside with the clumsy boots Thorn II had dug up God knows where, and strode to the mouth of the cave. Claws skirred on rock, and he had the impression of a lithe furry animal whisking off to one side. The cave opened on a hillside, similar to the one opposite and slanting down to a twisting, ice-choked stream. Overhead a gray, dreary sky seemed to be trending toward nightfall. The walls of the ravine shut off any more distant horizon. It was very cold. The scene was hauntingly familiar. Had Thorn II been insane, or gone insane? Why else should he have hidden himself in a cave in a near-arctic wild-life reserve? For that certainly seemed to be what he had done, despite the difficulty in picturing just how he had managed to do it in so short a time. A fine thing if, after getting back to his rightful world, he should starve to death in a reserve, or be killed by some of the formidable animals with which they were stocked. He must climb the hill behind him. Wherever he was, he'd be able to sight a beacon or skylon from its top.