Who were they? What were they doing here? Where were they going? At first he had a momentary fear lest they should see him perched up here on his point of vantage. Then he realized that the backing of rocks prevented his figure from showing against the skyline, which, together with the distance and the clouds of dust stirred up by the car itself, made the danger almost negligible. So he merely dismounted and, leaning against his horse, kept the glasses riveted on the slowly moving machine. The car advanced steadily until it reached a point about a quarter of a mile from the rough ground and a little distance north of where Buck stood. Then it stopped, and a capped and goggled head was thrust out of the tonneau. Buck could make out nothing definite about the face save that it was smooth-shaven and rather heavy-jowled. He was hoping that the fellow would alight from the car and show himself more plainly but to his disappointment the head was presently drawn back and the machine crept on, swerving a little so that it headed almost due north. Ten minutes later it halted again, and this time the two men got out and walked slowly over the sand. Both were clad in long dust-coats, and one seemed stouter and heavier than the other. Unfortunately they were too far beyond the carrying power of the binoculars to get anything more clearly, and Buck swore and fretted and strained his eyes in vain. After a delay of nearly an hour, he saw the car start again, and followed its blurred image until it finally disappeared beyond an out-thrust spur well to the northward. Stratton lowered his glasses and stood for a moment or two rubbing his cramped arm absently. His face was thoughtful, with a glint of excitement in his eyes. Presently his shoulders straightened resolutely. "Anyhow, I can follow the tracks of the tires and find out what they've been up to," he muttered. The difficulty was to descend from his rocky perch, and it proved to be no small one. He might have clambered down the face of the cliff, but that would mean abandoning his horse. In the end he was forced to retrace his steps along the twisting ledge by which he had come. From his knowledge of the country to the south, Buck had started out with the idea that it would be simple enough to reach the flats through one of the many gullies and canyons that fringed the margin of the hills further down. He had not counted on the fact that as the range widened it split into two distinct ridges, steep and declivitous on the outer edges, with the space between them broken up into a network of water-worn gullies and arroyos. "I ought to have known from the look of the north pasture that all the water goes the other way," he grumbled. "Best thing I can do is to head for that trail Bud spoke of that cuts through to the T-T ranch. It can't be so very far north."