"Why do you say that as if you felt sure?" demanded Tom Betts.
"Yes," put in Phil, eagerly, "you've got on to something, Paul; give us a chance to grab it, too, please."
"Sure I will," complied the scout master, cheerfully. "And I'm only surprised that one of you, always so quick to see such things, hasn't jumped on to this little game as soon as I have. Look back a short time, and you'll remember how we were scratching our heads over the tracks of wheels down in that big opening!"
"Wheels!" exclaimed Bobolink, with fresh excitement. "Well, I should say yes; and looks to me like we had 'em in our heads too, where the brains ought to be. Wheels, yes, and rubber-tired wheels too! Remember how they seemed to run up and down a regular track, and just went so far, when they gave out? Whoop! why, it's as easy as two and two make four. Anybody ought to have guessed that."
"Huh!" remarked Tom Betts, scornfully; "that's what they said, you recollect, when Columbus discovered America. After you know, everything looks easy. In my mind Paul goes up head. He's in a class by himself."
"And that forge might have been used, among other things, for doing all sorts of mending metal pieces connected with an aeroplane," Paul went on, smiling at Tom's tribute of praise.
"Not forgetting these sort of things," Bobolink observed, positively, as he took out a pair of bright new quarters, and jingled them musically in his hand.
"Well, we haven't had any reason to change our minds about that thing,—yet," said Paul. "But what strikes me as the queerest of all is the fact that while we must have been pretty close by when that aeroplane went up, how was it none of us heard the throbbing of the engine?"
They looked at each other in bewilderment. Paul's query had opened up a vast field of conjecture. One and all shook their heads.
"I pass," declared Tom.