Close as it had looked from the pass, the plain was yet a day and a night, spent in careful watching by turns, ahead of them. It was midmorning of the second day that they left the foothill breaks, and the grass of the open country was waist high about them. Travis could see it rippling where the coyotes threaded ahead. Then he was conscious of a persistent buzzing, a noise which irritated faintly until he was compelled to trace it to its source. The grass had been trampled flat for an irregular patch, with a trail of broken stalks out of the heart of the plain. At one side was a buzzing, seething mass of glitter-winged insects which Travis already knew as carrion eaters. They arose reluctantly from their feast as he approached. He drew a short breath which was close to a grunt of astounded recognition. What lay there was so impossible that he could not believe the evidence of his eyes. Tsoay gave a sharp exclamation, went down on one knee for a closer examination, then looked at Travis over his shoulder, his eyes wide, more than a trace of excitement in his voice. "Horse dung--and fresh!" 5 "There was one horse, unshod but ridden. It came here from the plains and it had been ridden hard, going lame. There was a rest here, maybe shortly after dawn." Travis sorted out what they had learned by a careful examination of the ground. Nalik'ideyu and Naginlta, Tsoay, watched and listened as if the coyotes as well as the boy could understand every word. "There is that also--" Tsoay indicated the one trace left by the unknown rider, an impression blurred as if some attempt had been made to conceal it. "Small and light, the rider is both. Also in fear, I think--" "We follow?" Tsoay asked. "We follow," Travis assented. He looked to the coyotes, and as he had learned to do, thought out his message. This trail was the one to be followed. When the rider was sighted they were to report back if the Apaches had not yet caught up. There was no visible agreement; the coyotes simply vanished through the wall of grass. "Then there are others here," Tsoay said as he and Travis began their return to the foothills. "Perhaps there was a second ship--" "That horse," Travis said, shaking his head. "There was no provision in the project for the shipping of horses." "Perhaps they have always been here." "Not so. To each world its own species of beasts. But we shall know the truth when we look upon that horse--and its rider." It was warmer this side of the mountains, and the heat of the plains beat at them. Travis thought that the horse might well be seeking water if allowed his head. Where did he come from? And why had his rider gone in haste and fear?