"Good advice, Roger, if it wasn't for one thing. I don't want to give them a chance to get out of our sight. Let us tie our handkerchiefs over the lower parts of our faces. Then they won't be able to recognize us--at least unless we get pretty close." With Dave's suggestion carried out, the chums leaped into the rowboat, and, this done, each took an oar. They pulled hard, and as a consequence reached the mouth of the little creek on the United States side in time to see those ahead just disembarking. "Where do you suppose they are going?" queried the senator's son. "That remains to be found out," answered Dave. "Duck now, so they won't see us." And with a quick motion of the oar he possessed he sent the flat-bottomed boat in among some tall grass which bordered the creek at this point. Ward Porton and those with him had tied up their boat and were walking to the higher ground away from the creek. Jarvey Porton paused to look back along the creek and the bosom of the river beyond. "I don't see anything on the river just now," he announced. "Look! Some one is coming from the other way!" exclaimed his son, suddenly. "Is that Lawson, the ranchman?" questioned Packard Brown, anxiously. "No, I don't think it is," answered Ward Porton. "They seem to be strangers," he added, a minute later. Two men and a well-grown boy were approaching. They came on slowly, as if looking for some one. "I'd like to know what those fellows want around here," came from Jarvey Porton, as he gave up looking along the river to inspect the newcomers. From their position in the tall grass bordering the creek, Dave and Roger looked from the Porton party to those who were approaching. Then, of a sudden, our hero uttered a low exclamation of surprise. "Look who's here, Roger! Ben Basswood and my Uncle Dunston! And Mr. Andrews is with them!" "Oh, Dave! are you sure?" "Of course I am! I would know my Uncle Dunston as far as I could see him. And you ought to know Ben." "My gracious, Dave, you're right! This sure is luck!" "I know what I'm going to do," decided our hero, quickly. "I'm going to send both of the boats adrift. Then, no matter what happens, those rascals won't have any easy time of it getting back to Mexico." In feverish haste Dave sent the flat-bottomed boat out into the creek once more. Roger assisted him, and a few strokes of the oars brought the craft alongside of that which had been used by the Porton party. Then the chums leaped ashore, threw all the oars into the water, and set both of the rowboats adrift. "Hi there! What are you fellows up to?" came suddenly from Packard Brown, who had happened to look behind him. "See, Jarvey, those two fellows have cast our boat adrift!" "Who are they?" demanded Jarvey Porton, and looked in some bewilderment at the two figures approaching, each with a handkerchief tied over the lower portion of the face.