“We can pick up their trail in the morning if we want to,” returned his chum, smiling. “How?” demanded Dig, interested. “Why, all we need do,” Chet explained, “is to go back to those mounds, find the trail of the buffaloes, and follow it. They left a trace that a blind man could scarcely miss to the point where we turned west. It’s easy.” “Whew!” blew Dig. “Of course! What a thickhead I am! We’ll get those buffaloes yet.” “I don’t know,” Chet returned thoughtfully. “Ought we to go so far from the Grub Stake trail? Father did not tell me to hasten; but I am sure he expected us not to delay much on the road. I’ll feel a whole lot better, too, when I’ve attended to these deeds,” and he patted his breast to make sure of the packet he carried. “Surely you wouldn’t drop the chase when we’re so near those beasts?” cried Dig. “We don’t know how near they are. Maybe they’re running yet,” returned Chet grimly. Their mounts quickened their pace and the boys fell silent. Twilight had fallen, and the immensity of the plains and their loneliness impressed the lads. Suddenly Chet started upright in his saddle and pointed ahead. “Look!” he cried. It was the gleam of water. There was no mistaking it. The horses snorted and broke into a trot. It was a fair-sized sheet of water, lying in a little saucer scooped in the plain—a “water-hole” in the West, but what would have been called a “frog-pond” in the East. Rushes and willows grew about it. There were several stunted trees, too, offering plenty of firewood if not much shelter. The stars were already appearing in the arch of the sky overhead, and that would be their tent-roof. The two chums became cheerful, however, as soon as they saw water and fuel. An open camp on a fair night like this had no terrors for them. They unsaddled their mounts, let them drink their fill, and then hobbled them on a flat piece of prairie next to the camp. The fire was built and the strips of venison toasted. They were ravenously hungry and the remainder of the haunch the robber had left for them now looked very small. There was no more hard-bread. “Whew!” sighed Digby, “I reckon we’ll have to start for Grub Stake bright and early in the morning, for we haven’t anything to eat!” “We still have coffee, and milk for it, and all these cooking things,” chuckled Chet. “Lots better off than many hunters. Lost all your desire to shoot a buffalo, Dig?” “Shooting a buffalo is all right, I don’t doubt,” returned his chum scornfully, “but chasing all over this country hunting the creatures isn’t much fun. Say, Chet!” “Put a name to it.” “What do you suppose ever scared that wolf so?” “The wolf that stampeded the buffaloes?” “Yes.” “You may have three guesses. But that’s why we’re going to keep watch and watch to-night,” Chet said grimly. “You don’t think it was another hunting party?” cried Dig.