“I’ll take him unawares some time,” he was saying to himself, as he stood on deck that afternoon, after they had tied up, with the sunlight around him, and looked out from under the shady branches of the tree to which the boat was fast; “and spring that name on him—call him Mr. Stackpole. If he can look me in the eye, and never show a sign, I’ll have to think I’m mistaken; but all the same, off this boat he goes at Memphis, if I have to get an ambulance, and send him to the hospital.” Bluff was seated, as he often might be seen, on the rail of the boat; while Will pottered over the tangled fish lines, for Jerry had taken a notion to put a new roll of film in the little camera, and was even then rubbing it up. Luther Snow, a blanket about his shoulders, sat near by, watching it all in a pleased sort of way. “Time was when I could stand anything, boys,” remarked the old man as he gathered this covering closer to his body; “and I reckon I’ve been through considerable all over the wide world, for a man who never had a cent that he didn’t earn himself. But I’m getting a little old now, you see. I begin to feel rheumatism in my bones, and sometimes I begin to believe that my days as a rover are nearly over.” Frank always listened when he started to speak of experiences in his checkered past. It often aroused the curiosity of the boy to understand how a man who, as he confessed himself, was only a common carpenter (and a mighty poor one at that, Frank would say to himself), had been able to get around in all the queer corners of the world that Luther Snow had. He seemed to know many foreign cities by heart, and spoke of certain things in a way that only one familiar with them could do. Well, there could be no doubt of one thing, and this was that Luther occupied the rôle of a mystery to Frank, a puzzle he could not wholly solve. If, then, he proved to be Marcus Stackpole, the very man against whom they had been especially warned, what did he want? Frank kept repeating that to himself time and again as he lounged there and in the light of the declining sun watched his chums; then turned his eyes in the direction of the man who had the blanket about his shoulders, and who seemed so satisfied to be with them on board Uncle Felix’s houseboat. It was Jerry who startled them all suddenly by calling out: “Hey! there’s a gray squirrel right over your head, Bluff! Watch me give the little beggar a scare, will you?” He reached over, and picked up one of a number of sticks of wood which had been brought on board at their last stop, being intended to serve as fuel for the little cook stove, after they had been chipped in half, perhaps. This was a short and heavy one Jerry had selected. Rising to his feet, he gave it one whirl around his head, and then let fly. Jerry had always been reckoned something of a thrower. He often played in the pitcher’s box before he went away from home, and was even now a promising fielder on the sub nine at college.