The morning passed without any adventures, and the afternoon sun was waning when at last Reuben entered a defile that was, as he recalled it, several miles long. On his left were stunted growths of trees and the sides of the mountains sloped gently back with the valley. On the opposite side, however, the cliffs were steep and the mighty crags in places hung directly over his pathway. He was following the bed of a stream, which was nearly dry, as the snows had largely disappeared from the slopes of the mountains. The sense of his absolute loneliness was resting more heavily upon him now that he was tired from the long ride.

Suddenly the pony stopped and trembled violently in every muscle. An instant later the frightened animal did its utmost to leap forward, and it was only by using all his strength that Reuben was able to restrain him. Then it was that he glanced behind him to discover the cause of the terror of his horse. His own alarm was hardly less when not more than twenty yards behind him he saw the crouching figure of a mountain lion. The savage beast evidently was following him, occasionally seeking the shelter of some huge rock, or climbing among the bushes. It was unusual, however, for such treacherous animals to come into the open, as the one behind him now was doing, and for a moment Reuben was at a loss to account for the tenacity with which the powerful beast had been clinging to his trail.

Instantly Reuben raised his rifle to his shoulder and fired. At that very moment, however, his pony, maddened by terror, suddenly leaped forward, and the aim of the young hunter was destroyed. It was plain an instant later that the savage mountain lion was unharmed.

[CHAPTER XVI—A MOUNTAIN LION]

Reuben was aware that if he permitted his pony to run, the beast would instantly pursue him. He knew also that it would not be long before the mountain lion would overtake the fleeing pony. As long as he moved slowly, he had been frequently informed by his companions, a lion, though it might creep close upon his trail, would not be likely to attack him. On the other hand, if he should show his fear by flight the courage of the lion instantly would be strengthened and it would follow and attack any man or animal that fled in this way from his presence.

The snorting and trembling of the pony he was riding were pitiful. The flanks of the swift little animal already were wet, and its eyes were rolling and bloodshot with terror. By a supreme effort, however, Reuben succeeded in bringing the pony to a walk, and though there were moments when his mount was so terrified that it almost crouched upon the ground, still he was able to prevent it from running. It was impossible now for the boy to reload his gun. The actions of the pony prevented him from holding his rifle sufficiently quiet to enable him to ram home the bullet.

Occasionally Reuben glanced behind him, and he was aware that the one long leap forward which the mountain lion had taken when the pony had first darted ahead had given place to a more wary and careful approach. The savage beast was creeping along the ground. For several yards it would advance in this crouching manner, and then when Reuben looked behind him it would leap back into the bushes or seek the shelter of some huge crag.

Reuben was carrying his rifle in his hands, ready to defend himself if the beast should leap upon the flanks of his pony. The lion was now not more than thirty feet behind him, and why it did not attack him the young trapper was at a loss to understand.

Reuben glanced anxiously at the sky, and his fears increased when he discovered that already the afternoon sun was below the rim of the mountain. Darkness would soon approach and would come, as he was aware, after the manner of the sunset among the towering mountains. Usually there was only a brief period of twilight. The day abruptly ceased and night with equal abruptness swept over the land. Confident that his perils would be greatly increased with the coming of night, Reuben was at a loss how he was to prevent the lion from following him, until in the darkness in some narrow defile it would leap upon its victim.

Again he glanced behind him at the beast, which now was motionless, crouched as if it had been a cat ready to spring upon a helpless and unsuspecting bird. A moment later, however, he saw it leap gracefully into the bushes and disappear from sight.