“He doesn’t seem to be hurt, Tom,” remarked Garret Jackson, Tom’s shop manager, as he laid Mr. Damon on a pile of coats and jackets which some workmen hastily spread on the roof. “Hurt! Bless my doctor’s bill, I’m not hurt at all!” exclaimed the odd man. “I’m shaken up, but I’m more worried about the plane than about myself. Is it all right, Tom? I tried to avoid the chimney, but I’m afraid one wheel grazed it.” “Yes, that’s what happened,” replied the young inventor, as soon as he had made sure his friend was not hurt and had had time to inspect the craft. “You damaged it a little. But I can easily put on another wheel. I have some spare ones for that model.” “Have you, Tom? That’s fine! Put one on and I’ll fly off your roof. You may charge me storage if I stay here too long,” and Mr. Damon laughed in a way which showed, better than anything else, that he had suffered no ill effects from the sudden ending of his flight. “Are you going to trust yourself again to that plane?” asked Mr. Jackson. “Of course I’m going to fly again!” cried the odd man. “A little bump like this doesn’t disturb me. I’ve been in worse smash-ups; haven’t I, Tom?” “Off hand, I should say you had,” was the smiling answer. “Besides, I want to learn how to run this jigger!” cried Mr. Damon, sitting up on the pile of workmen’s garments while the men gathered smilingly about him, for they all knew him. “What did I do wrong, Tom? Or is the steering gear out of order?” “It seems to be all right,” answered the young inventor, who had been looking at the mechanism. “Tell me just what happened.” “Well, as I say, I was coming over to see you. Or, if I didn’t say that before, I tell you now. I have a big offer for you, Tom Swift, a most important offer. I’ll get to that in a moment. But I was coming over in this plane, which I bought only yesterday, and I decided to fly across your shop and land in the meadow. “But, just as I got here, I felt the machine dip suddenly. First I thought I had struck an air pocket, but I didn’t have time really to decide what it was before I came down with a crash. Luckily I was able to straighten her out a little before I struck, so I made a slanting landing. Otherwise I might have gone through the roof.” “And right down on our heads!” exclaimed Ned. “Mighty glad you didn’t!” “So am I,” said Mr. Damon. “But what’s wrong, Tom? I want to know so that the same thing won’t happen again.” “I guess you forgot that you were in a monoplane instead of a biplane, Mr. Damon,” he answered. “You banked too much on the turn.” “That’s it, Tom! I remember now! I was making the curve to head straight for the meadow, and it was then a sort of side slip came.” “Yes,” remarked the young inventor, “you spilled too much air from beneath your wing tips. You see in a biplane, with two surfaces, the air is held in a sort of pocket and you can afford to make a sharper bank on the turn. But in monoplanes you must be more careful.”