The sight nerved Bob to the most desperate exertions. The blows of the rawhide quirt fell faster. Frowning brow and grim-set lips told of a determination which would never give up while the slightest hope remained. Faster, but not fast enough, tore his broncho.

From behind came the sound of a thundering cavalcade and shouts of encouragement. A cold chill seemed to strike his heart when the realization came to him that he was scarcely gaining on the runaway.

"Jump when you get the chance!" he yelled.

As his voice was flung to the breeze, Bob's broncho stumbled, and the rider, hurled violently forward on the animal's neck, felt its mane lashing his face. With a supreme effort, he recovered from the jarring shock.

"J-u-m-p!" he again shouted, in a ringing voice.

"J-u-m-p!" came high above the din of flying hoofs, as the five boys, perceiving that their leader's tremendous effort was doomed to failure, yelled with all the power of their lungs.

The cold, clear sunlight shone brilliantly on the whirlwind of dust and horsemen. Already the edge of the bluff stood before them with terrifying distinctness, and to the boys bringing up in the rear it seemed as if nothing now could save Jack Conroy from being dashed to pieces at the base of the cliff.

The steaming bronchos slackened their headlong pace—the race was over.

Meanwhile Jack Conroy was not as badly scared or helpless as every one imagined. He quickly saw that it was beyond his power to check the frenzied sorrel, and knew that his only chance to escape lay in keeping his wits about him.

Jolted and bumped, he still sawed desperately at the bit and struggled to keep his seat. Peering through narrowed lids, he kept his gaze fixed, with fascinated attention, upon the brow of the cliff. A mass of vegetation slightly to one side rose before him, and not a hundred feet beyond was the fateful goal.