Headed by Jack, the three Border Boys started on the run for the grove in which the horses had been picketed. Some of the animals were saddled and bridled, and for these they made a dash. They were not to escape without some difficulty, however, for, as they placed their feet in the stirrups, preparatory to swinging into the high-peaked saddles, a dozing trooper sprang up from a litter of opened hay-bales. He shouted something in Spanish, and made a spring for the head of the animal Jack bestrode. It was no time for half measures. The heavy quirt, with its loaded handle, hung from the horn of the saddle. With a quick movement, Jack secured it, and brought the loaded end down on the fellow's skull. He fell like a log, without uttering a sound. "Now, forward boys!" cried Jack in a low tone, "it's a ride for life." The others needed no urging. As rapidly as they could, consistent with making as little noise as possible, the three young horsemen rode out of the patch of woods in which the camp had been made, and emerged on the high road without being stopped. Suddenly, however, a sentry with a fixed bayonet, seemed to spring from the ground in front of them. He cried something in Spanish, to which Jack replied by driving his horse full at him. The fellow went down, and rolled over and over, as the horse's hoofs struck him. Before he recovered his feet, the Border Boys were upon the road and galloping for dear life. There was no use in caution, now. Everything depended, in fact, on putting as much distance as possible between themselves and the camp before their absence was discovered. Fortunately, their horses were fresh, powerful animals, with long, swinging gaits. They got over the ground at a wonderful rate, and Jack's heart began to beat exultingly. Not far distant lay some hilly ground, broken with deep gullies and thickly grown with wooded patches. Could they gain it, they would have a chance of concealing themselves. "Hullo! They've discovered we've gone!" exclaimed Jack suddenly, as behind them they could hear shots and bugle calls. "Don't spare the horses, boys; we've got to make that rough country." The quirts fell unmercifully on the big, powerful horses, and they plunged snorting forward. "We're kicking up dust enough to be seen ten miles," grumbled Walt. "Can't be helped," flung back Jack, "speed is what counts now." Before many minutes had passed, such good progress had they made that the edge of a clump of woods was reached, and they plunged rapidly into the friendly shelter. "Where to now?" gasped Ralph. "Right on! Right on!" shot out Jack. "Keep going till the horses drop, or they overtake us. It's our only chance." On and on into the wood, the hunted boys rode. Their wiry horses were flagging now, but still seemed capable of more effort. Over the rough ground, though, the pace at which they urged them was a killing one. Still, as Jack had said, it was "their only chance."