john sharp was more than surprised at the effect his piece of information had on tom swift. though the young inventor had all along suspected andy of having the missing plans, yet there had been no positive evidence on this point. that, coupled with the fact that the red-haired bully had not been seen in the vicinity of shopton lately, had, in a measure, lulled tom's suspicions to rest, but now his hope had been rudely shattered.

"do you really think that's his game?" asked mr. sharp.

"i'm sure of it," replied the youth. "though where he is building his aeroplane i can't imagine, for i haven't seen him in town. he's away."

"are you sure of that?"

"well, not absolutely sure," replied tom. "it's the general rumor that he's out of town."

"well, old general rumor is sometimes a person not to be relied upon," remarked the balloonist grimly. "now this is the way i size it up: of course, all i know officially is that andy foger has sent in an entry for the big race for the ten-thousand-dollar prize which is offered by the eagle park aviation association. i'm a member of the arrangements committee, and so i know. i also know that you and several others are going to try for the prize. that's all i am absolutely sure of.

"now, when you tell me about the missing plans, and you conclude that andy is doing some underhanded work, i agree with you. but i go a step farther. i don't believe he's out of town at all."

"why not?" exclaimed tom.

"because when he has an airship shed right in his own backyard, where, you tell me, he once made a craft in which he tried to beat you out in the trip to alaska, when you think of that, doesn't it seem reasonable that he'd use that same building in which to make his new craft?"

"yes, it does," admitted tom slowly, "but then everybody says he's out of town."

"well, what everybody says is generally not so. i think you'll find that andy is keeping himself in seclusion, and that he's working secretly in his shop, building a machine with which to beat you."

"do you, really?"

"i certainly do. have you been around his place lately?"

"no. i've been too busy; and then i never have much to do with him."

"then take my advice, and see if you can't get a look inside that shop. you may see something that will surprise you. if you find that andy is infringing on your patented ideas, you can stop him by an injunction. you've got this model patented, i take it?"

"oh, yes. i didn't have at the time the plans were stolen, but i've patented it since. i could get at him that way."

"then take my advice, and do it. get a look inside that shed, and you'll find andy working secretly there, no matter if his cronies do think he's out of town."

"i believe i will," agreed tom, and somehow he felt better now that he had decided on a plan of action. he and the balloonist talked over at some length just the best way to go about it, for the young inventor recalled the time when he and ned newton had endeavored to look into andy's shed, with somewhat disastrous results to themselves; but tom knew that the matter at stake justified a risk, and he was willing to take it.

"well, now that's settled," said mr. sharp, "tell me more about yourself and your aeroplane. my! to think that the red cloud was destroyed! that was a fine craft."

"indeed she was," agreed tom. "i'm going to make another on similar lines, some day, but now all my time is occupied with the humming-bird."

"she is a hummer, too," complimented mr. sharp. "but i almost forgot the real object of my trip here. there is no doubt about you going in the race, is there?"

"i fully expect to," replied tom. "the only thing that will prevent me will be—"

"don't say you're worried on account of what andy foger may do," interrupted mr. sharp.

"i'm not. i'll attend to andy, all right. i was going to say that my father's illness might interfere. he's not well at all. i'm quite worried about him."

"oh, i sincerely hope he'll be all right," remarked the balloonist. "we want you in this race. in fact, we're going to feature you, as they say about the actors and story-writers. the committee is planning to do considerable advertising on the strength of tom swift, the well-known young inventor, being a contestant for the ten-thousand-dollar prize."

"that's very nice, i'm sure," replied tom, "and i'm going to do my best. perhaps dad will take a turn for the better. he wants me to win as much as i want to myself. well, we'll not worry about it, anyhow, until the time comes. i want to show you some new features of my latest aeroplane."

"and i want to see them, tom. don't you think you're making a mistake, though, in equipping it with a wireless outfit?"

"why so?"

"well, because it will add to the weight, and you want such a small machine to be as light as possible."

"yes, but you see i have a very light engine. that part my father helped me with. in fact, it is the lightest air-cooled motor made, for the amount of horsepower it develops, so i can afford to put on the extra weight of the wireless outfit. i may need to signal when i am flying along at a hundred miles an hour."

"that's so. well, show me some of the other good points. you've certainly got a wonderful craft here."

tom and mr. sharp spent some time going over the humming-bird and in talking over old times. the balloonist paid another visit to mr. swift, who was feeling pretty good, and who expressed his pleasure in seeing his old friend again.

"can't you stay for a few days?" asked tom, when mr. sharp was about to leave. "if you wait long enough you may be able to help me work up the clues against andy foger, and also witness a trial flight of the humming-bird."

"i'd like to stay, but i can't," was the answer. "the committee will be anxious for me to get back with my report. good luck to you. i'll see you at the time of the race, if not before."

tom resolved to get right to work seeking clues against his old enemy, andy, but the next day mr. swift was not so well, and tom had to remain in the house. then followed several days, during which time it was necessary to do some important work on his craft, and so a week passed without any information having been obtained.

in the meanwhile tom had made some cautious inquiries, but had learned nothing about andy. he had no chance to interview pete or sam, the two cronies, and he did not think it wise to make a bald request for information at the foger home.

ned newton could not be of any aid to his friend, as he was kept busy in the bank night and day, working over a new set of books.

"i wonder how i can find out what i want to know?" mused tom one afternoon, when he had done considerable work on the humming-bird. "i certainly ought to do it soon, so as to be able to stop andy if he's infringing on my patents. yet, i don't see how—"

his thoughts were interrupted by hearing a voice outside the shop, exclaiming:

"bless my toothpick! i know the way, eradicate, my good fellow. it isn't necessary for you to come. as long as tom swift is out there, i'll find him. bless my horizontal rudder! i'm anxious to see what progress he's made. i'll find him, if he's about!"

"yes, sah, he's right in dere," spoke the colored man. "he's workin' on dat dragon fly of his." eradicate did not always get his names right.

"mr. damon!" exclaimed tom in delight, at the sound of his friend's voice. "i believe he can help me get evidence against andy foger. i wonder i didn't think of it before! the very thing! i'll do it!"