For an instant he towered over his helpless enemy, white-faced and hesitating. Then Stratton caught the hard impact of his boot against his side, and felt the edge of the rock slipping horribly beneath him. Powerless to help himself, his clutching fingers slid despairingly across the smooth surface. A blinding ray of sunlight dazzled him for an instant and vanished; the mountain trail flashed out of sight. His heart leaped, then sank, with a tremendous, poignant agony that seemed to tear him into shreds. Then blackness seemed to rush out of the gulch to enfold him in an impenetrable cloud of merciful oblivion. CHAPTER XXI WHAT MARY THORNE FOUND A few hundred yards away from the fence strung along the western side of middle pasture, Mary Thorne pulled her horse down to a walk and straightened her hat mechanically. Her cheeks were flushed becomingly and her eyes shone, but at the end of that sharp little canter much of the brightness faded and her face clouded. For the last week or more it had grown increasingly difficult to keep up a cheerful front and prevent the doubts and troubles which harassed her from causing comment. This morning she had reached the limit of suppression. Stella got on her nerves more than usual; Alf annoyed her with his superior air and those frequent little intimate mannerisms which, though unnoticed during all the years of their friendship, had lately grown curiously irksome to the girl. Even Mrs. Archer's calm placidity weighed on her spirits, and when that happened Mary knew that it was high time for her to get away by herself for a few hours and make a vigorous effort to recover her wonted serenity of mind. She told herself that she was tired and jaded, and that a solitary ride would soothe her ragged nerves. And so, at the first opportunity after breakfast, she slipped quietly away, saddled her favorite horse, Freckles, and leaving word with Pedro that she would be back by dinner-time, departed hastily. It was rather curious behavior in a girl usually so frank and open, and free from even a suspicion of guile, but she deliberately gave the Mexican an impression that she was going to join the men down in south pasture, and as long as she remained within sight of the ranch-house she kept her horse headed in that direction. Furthermore, before abruptly changing her course to the northwest, she pulled up and glanced sharply around to make certain she was not observed.