The shade of the cottonwoods was pleasant. Slone found this valley oppressively hot. There was no wind and the sand blistered his feet through his boots. Wildfire held to the Indian trail that had guided him down into this wilderness of worn rock. And that trail crossed the stream at every turn of the twisting, narrow valley. Slone enjoyed getting into the water. He hung his gun over the pommel and let the water roll him. A dozen times he and Nagger forded the rushing torrent. Then they came to a box-like closing of the valley to canyon walls, and here the trail evidently followed the stream bed. There was no other way. Slone waded in, and stumbled, rolled, and floated ahead of the sturdy horse. Nagger was wet to his breast, but he did not fall. This gulch seemed full of a hollow rushing roar. It opened out into a wide valley. And Wildfire's tracks took to the left side and began to climb the slope. Here the traveling was good, considering what had been passed. Once up out of the valley floor Slone saw Wildfire far ahead, high on the slope. He did not appear to be limping, but he was not going fast. Slone watched as he climbed. What and where would be the end of this chase? Sometimes Wildfire was plain in his sight for a moment, but usually he was hidden by rocks. The slope was one great talus, a jumble of weathered rock, fallen from what appeared a mountain of red and yellow wall. Here the heat of the sun fell upon him like fire. The rocks were so hot Slone could not touch them with bare hand. The close of the afternoon was approaching, and this slope was interminably long. Still, it was not steep, and the trail was good. At last from the height of slope Wildfire appeared, looking back and down. Then he was gone. Slone plodded upward. Long before he reached that summit be heard the dull rumble of the river. It grew to be a roar, yet it seemed distant. Would the great desert river stop Wildfire in his flight? Slone doubted it. He surmounted the ridge, to find the canyon opening in a tremendous gap, and to see down, far down, a glittering, sun-blasted slope merging into a deep, black gulch where a red river swept and chafed and roared. Somehow the river was what he had expected to see. A force that had cut and ground this canyon could have been nothing but a river like that. The trail led down, and Slone had no doubt that it crossed the river and led up out of the canyon. He wanted to stay there and gaze endlessly and listen. At length he began the descent. As he proceeded it seemed that the roar of the river lessened. He could not understand why this was so. It took half an hour to reach the last level, a ghastly, black, and iron-ribbed canyon bed, with the river splitting it. He had not had a glimpse of Wildfire on this side of the divide, but he found his tracks, and they led down off the last level, through a notch in the black bank of marble to a sand-bar and the river.