The sun had set shortly after they started away from the ranch, and the sky took on the brightest red colors that could be imagined. But neither of the boys felt in a humor to admire the view. They had business on their hands of a nature to engross their every thought--Jimmy, with the control of his vicious mottle mount; and Ned, in calculating what the ill-natured suspect might attempt, in order to outwit those who were pitted against him. Night settles down promptly after sunset in this far southern country, there being very little gloaming, such as people living in more northern latitudes are accustomed to. But as the moon was due to peep above the eastern horizon in short time this was not apt to give them any trouble. Besides, Chunky and his riders knew every rod of the plain and could easily avoid such places, where the prairie dogs had their underground homes and which have been the means of breaking the legs of many valuable horses. Ned had already noticed how careful Chunky was to keep in a certain position on the gallop. Here he could watch Sloper and at the same time be ready to draw quickly upon him should the suspect attempt any crooked business. "He doesn't trust the man any further than he can see him," Ned was telling himself, as he noticed this game that was being played between the two men; and, at the same time, he meant to try and keep his own eye on the slippery customer, in so far as the conditions would allow. The evening star shone in the western sky and they were making in a straight line away from it, Ned noticed. This told him what the course was. While Jimmy was apparently paying not the least attention to such things, content to trust himself in the hands of the puncher guide, Ned believed in knowing for himself. There might arise an occasion where he would be thrown on his own resources; and, in such an event, it would be a valuable asset to know just which way to head, in order to fetch up at the ranch house. That was scout tactics and scout practice--being prepared against possible need. And now over the low rim in the far east, where the squatty hills lay against the sky line, a yellow glow began to appear. It was the moon rising to fulfill a night's vigil as sentinel while men slept. Ned greeted it as an old friend, and Jimmy, too, expressed his satisfaction over seeing it come upon the scene, for Jimmy and darkness never did agree, and that was one reason he always wanted to keep the fire burning through the night while in camp, during the period when there was no moon. As they drew closer to the hills, Ned began to calculate just about how many miles they would have to drive the herd once they managed to round it up and get it on the run for home. He knew from what he had been told that what had taken them not more than an hour to cover, as the crow flies, would mean at least four times that length of time with the cattle.