Feeling anything but as confident as he looked, Rob boldly put his foot in the heavy wooden stirrup with its big leather tapadero covering, and swung into the saddle. Hardly had he touched it when a strange thing happened. The boy felt as if an explosion must have occurred directly beneath him, and he was being shot skyward by it. The next instant the sensation changed, and as the broncho struck the hard ground of the corral, all four legs as stiff as drum sticks, Rob felt as if every bone in his body was in process of dislocation. "Stick to her, boy! Yow-ee-ee!" Blinky, roaring with laughter, shouted the advice. At this moment, too, just when Rob would much rather not have had any spectators about, several cow-punchers appeared as if by magic, and perching themselves on the corral rails, settled down to enjoy the spectacle. "Whoop!" they yelled. "That's a regular steamboat bucker." "Go on, boy! Grip her!" "Don't go to leather!" These and a hundred other excited exclamations were borne dimly to Rob's ears as the buckskin threshed about, trying in vain to rid itself of the troublesome boy. How he did it Rob never knew, but he stuck like a cockle-burr, and that without "going to leather," or, in other words, gripping any part of the saddle. He must have been a born rider to stand the antics of the maddened cayuse as he did. One second the little brute, tiring of bucking, would rear backward as if it must overbalance, and the next it would be fairly standing on its head. Once it lay down and tried to roll over, but the high horn of the saddle prevented this. As it collapsed to the ground, Rob skillfully slipped off, and when it struggled upon its feet again, the boy was standing over it and was as firmly in his seat as ever by the time the animal was ready for a new performance. All at once the buckskin made a mad rush for the corral fence. It was five feet in height, and Rob turned sick as he faced what seemed inevitable disaster. The yells of the cowboys, however, made him determined to stick it out. "I've stood it all this time. I'll stay with it if it kills me," thought the boy. The next instant the little broncho rose at the fence. The bars rose in front like an impassable wall. "He'll never make it," was the thought that flashed through Rob's head. But even as the fear of a direful crash flashed through his mind, the active little animal he bestrode had cleared the barrier, its hind hoofs just splintering the upper edge of the top rail. The buckskin alighted on the other side, trembling and sweating, with expanded nostrils and heaving flanks, but its ears were no longer back, nor did its eyes show white. The broncho seemed to have realized that it had played its trump card and lost. "Get up!" cried Rob, kicking the shivering pony in the sides.