Treve slackened speed. He glanced around him. The houses had grown few and straggling. He was on the compact little city’s outskirts. Ahead of him arose green foothills. Toward them he bent his pavement-bruised feet. Assuredly there was no sense in trying to find Joel Fenno in that hell of unfriendly humans behind him. There was no trace of the old man. And Treve did what the wisest of lost collies usually do. He headed for home. On he went, until he had breasted the nearest green slope of the ridge which divided the fertile valley from the desert beyond. Almost at the summit, he found a little trickle of water, from a hilltop-spring not yet dried by the approaching summer. There he paused; and drank long and greedily. His thirst assuaged, he stretched himself and clambered to the crest of the ridge. Pausing again, he lifted aloft his dainty muzzle; and sniffed. For perhaps two minutes he stood thus, testing the breeze with quick, comprehensive intakes of breath. From side to side he moved his head and forequarters; until presently he stood still; verifying the hint the air had brought him. Then, without a shadow of indecision in mind or in gait, he set off down the desertward side of the ridge. He knew the course he must take. (If perhaps this action of Treve’s be scoffed at, as nature-faking, there are a dozen authentic cases of the sort. How a collie can get his direction in the way just described, is past human knowledge. But that such direction _is_ gotten in that way cannot be denied.) Thus it was that the great dog began his hundred-mile homeward journey, across unknown land and guided solely by his mysterious sixth sense. Down the hill he went, never breaking that deceptively rapid choppy wolf-trot of his. In another half hour his feet had left the springy turf and ridges of the hill and were pattering across the prickling gray sands of the desert. On he went; while the sun dipped past the meridian; on into sweltering afternoon. Here was no chance for thirst-quenching; no chance for adequate shade; no chance for anything but grim endurance. The collie’s pink tongue lolled far out. His eyes were bloodshot from sand and from heat. The mud on his coat had caked and dried; as had the blood from the graze on his flank. He was suffering from thirst, from fatigue, from reaction. But he kept on. At sunset, he had his first alleviation of discomfort. Trotting exhaustedly over the top of a gray sand dune he saw at its base, in front of him, a black and white animal, about the size of a cat. The animal saw and heard him. Yet it made no hurry to get out of his way. Skunks know from experience that few larger animals willingly take a chance of attacking them. But Treve was as hungry as he was thirsty. All day he had been on the move; and he had eaten nothing. With express train speed he dashed downward, at this possible dinner. The skunk wheeled, bracing its four feet firmly in the sand; tail aloft.