“Kind o’ light and flimsy,” suggested the captain, when they finally quit work.

“Sure,” admitted Andy. “It wouldn’t hold at all that way. It won’t be rigid until we get the wire braces on. Then we’ll tune her up like a fiddle. This string and glue don’t do much but hold the frame together until we get the wires attached. They’ll brace her like a bridge span.”

The sawing of the spruce strips for ribs—pieces 6 feet long by ¾ inch thick and an inch wide—was the program for the next day. Captain Anderson adjusted the small power circular saw that was a part of his outfit, and the roughing of the slender pieces was soon accomplished. As each had to be delicately planed, sandpapered, and shellacked, this job ran into night again.

That evening, Mrs. Leighton began to wonder if she might not get a letter from her husband the next day in relation to the little estate and its disposition.

“I hope not,” whispered Andy to his friend, the captain. “He’ll likely put a crimp in my airship plans.”

“Put a crimp in your airship plans?” repeated Captain Anderson soberly. “What have you got to do with the airship? Aren’t you working for me? It’s your father and I who are partners.”

“Oh, of course,” replied the boy. “Of course—I forgot. But he may not want me to work on it.”

“That needn’t stop the work,” exclaimed the captain. “I think I’ll go ahead just the same. I reckon I’ve got a sort of interest in the engine, and, as for the bird-tail rudder, I can give that up if he wants it. But he won’t; he’s a mechanic.”

The letter did not come the next day, but when it did, in the middle of the following week, it was even enthusiastic about the possibilities of the discovered model, and congratulated Mrs. Leighton on her good luck in being able to make an arrangement with Captain Anderson to work out the idea. It said nothing about Andy’s work on the testing apparatus. This was probably because of Mr. Leighton’s special interest in his wife’s description of her brother’s estate. How much this was, was indicated by his suggestion that no part of the property be sold, as he was arranging, if possible, to come to Florida in about two weeks.

When Mrs. Leighton read this, Andy did not “hurrah.” Instead, he made a quick calculation. Then he smiled. In two weeks the aeroplane would be completed, and someone would have tested it.