"I judge from that you are a good shot on the wing," continued Archie. "Let me advise you to keep both eyes open; for the first thing you know, you'll see us disappearing over the tops of these mountains. Each of us has a patent, duplex, double-back-action flying-machine in his pocket." Archie was going on to explain to the Ranchero the principles on which his imaginary flying-machine operated, when the call to supper interrupted him. During the meal, the robbers were quite as polite as they had been at dinner. They gobbled up every thing within their reach, devouring it greedily, as though they feared that somebody might get more than his share, and the boys, having learned by experience, that, when one sojourns among Romans, it is a good plan to do as Romans do, snatched what they liked best, and ran back to their blankets. "Look at Benedict," said Johnny, speaking as plainly as a mouthful of cracker would permit. "He's hot about something." Arthur was sitting on the ground beside the robber chief, to whom he was talking earnestly, and even angrily, judging by the frantic manner in which he flourished his arms about his head, and struck with his fists at the empty air. Pierre was listening attentively, and so were all the other members of the band, who appeared to be deeply interested in what he was saying. Arthur had told the chief that his secret was discovered, and Pierre had urged him to use every exertion to allay the suspicions of the boys. "You don't know them as well as I do," said the Ranchero; "and, if you will take my advice, you will try to make friends with them again." "That's something I'll never do," said Arthur, decidedly. "Shall a gentleman's son stoop to beg the good-will of a lot of young Arabs? Not if he knows himself; and he thinks he does. They have found me out, somehow, and I don't care if they have. I may as well throw off the mask entirely. I'll let them see that, while they are prisoners, and bound hand and foot, I am at liberty to go and come when I please." When Arthur said this, he was gazing into the fire, and consequently did not see the significant glances which the robber chief exchanged with his men. It might have astonished him to know that he was not free to go and come when he pleased; and that Pierre, in spite of all his promises to the contrary, intended to demand twenty thousand dollars for him, as well as for the others. When Frank and his friends had eaten their supper, they began to make preparations for the night, by collecting a pile of dried leaves and grass, over which they spread their blankets, placing the saddles at the head of the bed, to serve as pillows. When the couch was completed, it was very inviting, and, had it not been for the knowledge of the fact that they were to be bound hand and foot, they would have been sure of a good night's rest.