A barn, large and vacant, would be an excellent place in which to hide the proceeds of a pirate raid. Lest--possibly--the barn should recognize him and hide itself, Mr. Gubb first went to his office in the Opera House Building, disguised himself as a hostler, with cowhide boots, a cob pipe, a battered straw hat, and blue jean trousers. Lest his face be recognized by the barn he wore a set of red under-chin whiskers, which would have been more natural had they been a paler shade of scarlet. Thus disguised, he crept softly down the Opera House Building stairs and ran full into Billy Getz, Riverbank's best example of the spoiled only-son species, and the town's inveterate jester. Mr. Getz put a hand on Mr. Gubb's arm. "Sh-h!" he said mysteriously. "Not a word. Only by chance did I recognize you, Mr. Gubb. Now, about this pirate business--it has to stop." "I am proceeding to the deteckative work preliminary to so doing," said Mr. Gubb. "Good!" said Billy Getz. "Because I can't have such things happening on my Mississippi River. I hate to see the dear old river get a bad name, Mr. Gubb. I'm just organizing the Dear Old River Anti-Pirate League--to suppress pirates, you know. And we want you as our official detective. In the meantime--Greasy! That's all I say--just Greasy! Tough-looking character. Lives in a barn." [Illustration: HE WORE A SET OF RED UNDER-CHIN WHISKERS] "I am just proceeding to locate the whereabouts of the barn," said Mr. Gubb. "That's easy," said Billy Getz. "Hampton's barn--Eighth Street alley. I know, because I've been there. He's doing our scenery for the Kalmuck summer show. You go straight up this street--or no, _you'd_ go in the opposite direction, and three miles into the country, and back across the cemetery, as advised in Lesson Thirteen, wouldn't you?" "There are only twelve lessons," said Mr. Gubb haughtily and stalked away. He went, however, to Hampton's barn, climbed in through the alley window, and searched the place. The barn contained nothing of interest. A cot stood at one end of the hay-loft; and stretched across the wall at the other end was a canvas on which was a partly completed scene of a ruined castle, with mountains in the distance. On the floor were pails and brushes, bundles of dry colors, glue, and the various articles needed by a scene-painter. Mr. Gubb looked behind the canvas. No loot was concealed there. He returned to his office, discarded his disguise, and went back to the Himmeldinger house. Seated on the front steps, quite neglecting his work, was Greasy, and beside him sat a girl. "This," said Greasy, "is Maggie Tiffkins. Youse ought to know her. Mag, consider this a proper knockdown to P. Gubb, my boss." That night the Silver Sides was attacked by the pirates on her return from Derlingport. The next morning Mr. Gubb awaited Greasy's coming impatiently, hoping for a new clue, but Greasy had none. He was glum. He had had a quarrel with Maggie, and he was cross.