“Why, I must have had a dozen letters about your carryings on,” continued the old sportsman, still laughing at the puzzled looks on their faces; “and Marcus did you all justice, I’ll wager, for he’s a good hand at describing things, Marcus is. But all the same, I’m going to have you tell me everything that happened, from the time you started out. I’m deeply interested in the voyage you made; and unless I miss my guess, you’re just the stripe of young heroes the accounts said.” “But, Uncle, we can’t tell you anything at all until you satisfy our curiosity,” declared Will, resolutely. “I suppose that’s only natural,” the gentleman remarked, nodding. “Why, just look at it yourself, Uncle,” Will went on, as the spokesman for the four chums, “ever since I got your letter some months back, while still at college, we’ve been hammering our brains to understand just what it all meant. We had all sorts of ideas about it. One thought this Marcus Stackpole must be some bitter enemy of yours, who wanted to do you an injury.” “And see here,” demanded Uncle Felix; “which one was it who was always so positive that I had some valuables secreted somewhere behind the paneled walls of the cabin, and kept on rapping and tapping every chance he got, trying to find the treasure trove?” Jerry turned red, but he stood up manfully before the quizzical eyes of the old gentleman. “That was I, sir,” he said, boldly. “I thought it was a good guess, after reading that letter you wrote our chum, Will. But I gave that up when we learned that our passenger, Luther Snow, must be the man, Marcus Stackpole. Because I saw then how silly the thing looked. If there had been any valuables hidden, and he knew where to find them, he wouldn’t have stuck to us like he did, but skipped out.” “That’s correct, I guess, Jerry,” commented Mr. Milton. “And now to lift the curtain and let you understand what it was all about. Just a little wager, my boys, between myself and my friend Marcus; who has been my comrade on many a hunt through African wilds.” “A wager!” faltered Bluff, weakly, looking at Frank; who smiled, as though some such idea might have flitted through his mind some time or other, to be dismissed as out of the question. “Why, yes,” continued the owner of the houseboat. “We had heard a great lot of stuff about you four boys. My sister-in-law even took the trouble to send me some clippings concerning a rescue you made of a balloonist from the waters of the Mexican Gulf. So Marcus and myself got to discussing things, and as I had that houseboat up North, I proposed that I get you four to take a long voyage down the big Mississippi during your vacation, which was near at hand.” “And that was something we’ll always thank you for, Uncle!” cried Will; “because we’ve surely had one of the finest times of our lives.”