"Oh, tell me about that!" jeered the cowboy. "Two strips of cloth, one above the other, with an engine between 'em and a propeller behind! Fine! You'd look pretty a mile high in that thing!"
"This," said Matt, taking the model on his knee, "is the fruit of several hundred years of thought and study."
"Sufferin' buzzards! If I couldn't think up an arrangement like that in two minutes, and make it in three, I'm a Piute."
"When you understand it, Joe, you'll think differently. An aëroplane is like a kite, but instead of a string to pull it against the air, it has a propeller to push it. It's easy enough to fly a kite, but when you put a man in the kite, and a gas engine and other machinery, and take away the string that connects the kite with the earth, you're confronted with problems that it has taken centuries to solve."
"Keno!" spoke up McGlory. "And do you mean to say, Matt, that those two pieces of cloth have guessed the riddle?"
"They'll come pretty close to it," asserted Matt. "The thing that bothered, you see, was keeping the centre of wind-pressure coincident with the centre of gravity so the machine wouldn't turn turtle, or——"
"Help!" fluttered McGlory, throwing up his hands.
"A German named Lilienthal tried and failed, and so did an Englishman named Pilcher. It remained for the Wright brothers to work out the conundrum. Lilienthal and Pilcher shifted weights to keep their machine right side up in the air, but the American scientists shift the ends of the wings, or planes. Traquair's invention does away with the shifting of weights or planes. Look here, Joe."
Matt pulled a diminutive lever affixed to a platform in the middle of the lower plane. The ends of the left-hand wings drew in, and the ends of the right-hand wings simultaneously extended. By pulling the lever the other way, a contrary movement was effected.
"Sufferin' blockheads!" muttered the cowboy, pushing his fingers desperately through his thick hair. "I'm only in the primer, pard, and you're leading me through the hardest part of the fifth reader. Shucks!"