But noon came, and still the trail led him on. He had plenty of time, so did not hurry. He could do nothing alone, other than to discover the retreat, and then he would make for his rendezvous with the surgeon-scout, and together they would plan their future movements. But night came on, and found him still on the trail. He was compelled to go into camp, for he could not follow it by night, and he soon made himself comfortable. Again he started after daybreak, and a ride of several hours caused him to say: "This trail is surely leading direct to the Grand Canyon of the Colorado. Can they have sought that weird land for a retreat?--yet why not, for no safer one could be found." Within an hour more he felt that the country had a familiar look, and he was not long in discovering upon riding a few miles farther, that he had ridden right along there with Doctor Dick when on the trail of Andrew Seldon. Suddenly he came upon the grand vista of the canyon, and at once drew rein. There before him was the mighty view that had so impressed him on his former visit, and he knew that the outlaws must have found a retreat in the depths of the Grand Canyon. Not daring to go farther on horseback, he rode off the trail to find a hiding-place for his horse, and, after a search, discovered a little glen where he felt that he would be safe, unless his trail was discovered and he was tracked there. There was a pool of water in one end and grass about it, so he staked his horse out, feeling that he could at least subsist comfortably there for a couple of days, should he be kept away that long. Hiding his saddle and bridle he set out on foot, with a couple of blankets strapped on his back, his bag of provisions, rifle, lasso, and belt of arms. He went back to the trail and again took it up where he had left it to hide his horse. Every step forward now was one of caution, for the country was open in places, and he did not know what moment he might come upon a party of outlaws and have to fight for his life. But he reached the rim of the canyon by dark, and a short search revealed to him that the trail down into the depths of the tremendous chasm had been discovered also by the road-agents, and their tracks led down into it. The night passed with a cold supper and breakfast, and then he set off on foot down the dizzy pathway leading to the bottom of the canyon, for now he felt sure that he would discover the lair of the outlaws, and that done and his own presence unknown to them, he could arrange for an attack upon them at his leisure. CHAPTER XXXVII. THE MINER'S MISSION. The gold-hunter, Andrew Seldon, rode on his way from his retreat in the canyon, determined to risk his life by returning to Fort Faraway and reporting the presence in the Grand Canyon of the masked outlaw band. If recognized as Sergeant Wallace Weston, under sentence of death, he would be at once arrested and his execution would follow.