"Not unless he sneaked in the barn some night," went on the machinist, who seemed to have little regard for the former lieutenant. "Well, there's no way of telling for certain, so we had better say nothing about it," decided Dick. "Then, too, any of us might have accidentally dropped the waste in the tank while we were working around the ship. I guess we'll call it an accident." "But it must have been in the tank for some time," argued Larry Dexter, "and yet it only stopped up the pipe a little while ago." "It was probably floating around in the tank, doing no damage in particular," explained Mr. Vardon. "Then, when we made the ship tilt that way, to test the stabilizer, the gasolene shifted, and the waste was flushed into the pipe. But we're all right now." This was proved a little later when the motor was started with no trouble whatever. There was not a very good place to make a start, along the edge of the stream, but Dick and his chums realized that they could not always have perfect conditions, so they must learn to do under adverse ones. "Look out of the way!" warned the young millionaire to the assembled crowd. They scattered from in front of the craft. The motor throbbed and thundered up to high speed, and then the propellers were thrown into gear. The big blades beat on the air, the ship moved slowly forward. It acquired speed, and then, amid the wondering comments and excited shouts of the crowd, it soared aloft, and glided through the air to a great height. "Off again!" cried Dick, who was at the wheel. The trip back to Hamilton Corners was made safely, and without incident worthy of mention. The four young men took turns in working the various controls, so as to become familiar with them, and Dick paid particular attention to Larry Dexter, who needed some coaching. "I'll get a good story out of this for my paper," said the young reporter, who was always on the lookout for "copy." "Well, we've proved that she will fly, and take care of us even when an accident happens," remarked Dick, when the craft had been put back in the barn. "Now we'll groom her a bit, put on the finishing touches, and we'll be ready to try for that prize. The time is getting short now." "I hope you win it," said Mr. Vardon. "I shall feel responsible, in a way, if you don't." "Nothing of the sort!" cried Dick. "Whatever happens, I've got a fine airship, and we'll have a good time, even if we don't get the twenty thousand dollars." The next week was a busy one, for there were several little matters about the airship that needed attention. But gradually it was made as nearly perfect as possible. Then, one morning, Mr. Hamilton, who had some business to transact with Uncle Ezra, said to Dick: