Glen borrowed a pair of spurs, soothed the mule for a moment, sinched the girth a trifle tighter, and, with a sudden leap, vaulted into the saddle. For an instant the animal remained motionless with astonishment; then he bounded into the air, and came down with all four legs as stiff as posts. The shock would have been terrible to the boy, had he not lifted himself from the saddle and supported his whole weight in the stirrups. The mule repeated this movement several times, and then began to plunge and kick. But the saddle in which Glen sat was a deeply hollowed, high-pommelled, Mexican affair, built for just such occasions as this, and so the plunging might have been kept up all day without disturbing the rider in the least.