The river at this point was broad and shallow and contained numerous sand-bars. Almost before they knew it the craft containing our friends ran up on one of the bars and stuck there. In the meantime Ward Porton continued his efforts to gain the shore. "What's the matter, Dave?" cried Roger, when he saw our hero stop rowing. "We are aground," was the answer. "Here, Roger, get to the stern of the boat with me, and we'll see if we can't shove her off again." With the two chums in the stern of the craft, the bow came up out of the sand-bar, and in a few seconds more Dave, aided by the current of the stream, managed to get the rowboat clear. But all this had taken time, and now the two chums saw that Ward Porton had beached his boat and was running across the marshland beyond. "I'm afraid he is going to get away," remarked Roger, dolefully. "Not much!" answered Dave. "Anyway, I'm not going to give up yet," and he resumed his rowing. "Here, let me take a turn at that. You must be getting a little tired," said Roger, and he insisted that Dave allow him to do the rowing. Soon they reached the Mexican shore, at a point where there was a wide stretch of marshland with not a building in sight. They had gotten several glimpses of Ward Porton making his way through the tall grass. The trail was an easy one to follow. "Come on! We'll get him yet!" muttered Dave, and started off on the run with Roger behind him. They had just reached an ill-kept highway when they heard shouting in the distance. They saw Ward Porton running wildly in the direction of a set of low buildings, evidently belonging to some sort of ranch. As the former moving-picture actor disappeared, a band of Mexican cavalry swept into view. "Quick, Roger! Down in the grass!" cried Dave. "We don't want those soldiers to see us! They may be government troops, but they look more like guerrillas--like the rascals who raided the Tolman ranch!" "Right you are," answered the senator's son. And then both lay low in the tall grass while the Mexican guerrillas, for they were nothing else, swept past them. CHAPTER XXVIII A STRANGE DISCOVERY As nearly as Dave and Roger could calculate, there were about two hundred of the Mexican guerrillas--dirty and fierce-looking individuals, led by an officer wearing an enormous hat and a long, drooping mustache. The entire crowd looked disreputable in the extreme, and the youths could not help but shudder as they gazed at the cavalcade. "My gracious, Dave! do you call those revolutionists?" remarked Roger, after the last of the horsemen had disappeared down the roadway. "They may be revolutionists, Roger. But to my mind they look more like bandits than anything else. Under the pretense of aiding Mexico they probably steal whenever they get the chance." "I'd hate awfully to fall into their clutches. I think they'd rob a fellow of every dollar he had."