"Guess you're right there, Frank, it would seem humdrum like if we didn't have to think of him every little while, and what new schemes he was planning to get the better of the Bird boys. And say, some of his games kind of dazzle a fellow, if only there wasn't so much meanness about 'em. When Perc gets to hating a fellow he doesn't stop half way, but goes the whole hog. Why, more than a few times he's given us a big scare, trying to do some stunt that would make us look small; and at the risk of sending us all down a thousand or two feet. After all, I'm beginning to believe I'd sleep sounder if Percy Carberry took to some other play, and let aeroplanes alone."

"Well, he seems just as wild about them as ever, and so I reckon he'll just keep on bothering us to the end of the chapter. But what are you looking at, Andy?" and Frank also turned his eyes down toward the fringe of quince trees that marked the old lane leading to the barnyard from the road.

"I thought I saw some one coming over there, and if it turned out to be our good friend, the profess, p'raps we'd be wise to skip out before he sighted us, Frank."

"Here, let's step back out of sight, anyhow, so as to be ready to slip away if it is our man," and Frank drew his companion around the corner of the house, from which point they could still keep watch over the lane.

Half a minute later Andy whispered:

"There, I saw him again, Frank, and as sure as anything it must be Casper. He's a little man, wearing brown glasses to keep the bright sun from his eyes, and yes, he's carrying a butterfly catcher's net over his shoulder. Shall we disappear?"

"I think that would be our best move, Andy; and lucky enough we've got the chance to slip around here, and get back of the barn before he comes along," with which the two boys hastened to follow out the plan suggested.



CHAPTER XVI

THROWING OFF THE MASK

"Do you think he saw us, Frank?" asked Andy, after they had found a place where they could peep around a corner, without being discovered.

"Well, that's more than I can say," the other replied. "We took every precaution, and unless he has mighty sharp eyes he couldn't have glimpsed us."

"And you think it's safe for us to stay here, eh, Frank?"

"Certainly," replied the other. "We're in a position to make a move any old way from here. There isn't one chance in ten of his coming around the corner; and if he does make a show of doing that, why we can be sitting here, playing mumble-de-peg, or something like that, just as if we didn't care whether school kept or not."

"Bully for that; who cares for expenses? Look, Frank, I was right, you see, for it was the little profess after all."

"Yes, sure enough. Careful now, Andy, and don't let him see you peeping. That'd give the whole thing away quicker than anything else."

They had both selected positions where they could see without attracting attention. And it was with considerable eagerness that they fastened their eyes on the figure of the small, wiry man who was sauntering along toward the farmhouse, carrying a butterfly-net across one shoulder, while with his other hand he held a queer-shaped black case, which, as Sallie said, contained his more recent captures in the way of beautiful and rare moths and insects.

"That's his stiff arm, Frank; see how he moves it—the one hanging down, I mean, with black box—good gracious! now, I wonder—"

"H'sh!" whispered Frank, "not so loud; he might hear you."

"Not with the roosters crowing like they are," said Andy confidently. "But just glimpse the black box would you, Frank?"

"I am looking," returned the other.

"He calls it the receiver for his new butterflies, but looks more like a kodak to me," Andy went on. "But d'ye know what I thought, Frank?"

"Tell me," whispered the other, still watching the professor, who had come to a stop at some little distance away, and seemed to be busily engaged looking back of him, as though laying out plans for an afternoon campaign among the bright winged butterflies.

"Why, how easy for him to tear out the inside works of a camera box like that, and make use of it for a better purpose, see?" Andy went on to say.

"Oh! now you've got a bright thought for a fact," Frank sent back, careful not to raise his voice above that cautious pitch.

"Well, it could be done; and I guess that little black box'd hold about all the money and securities that the bank lost. They say the thieves only picked out the papers they could dispose of, and left all the rest, which would indicate that the second yegg must have been in the banking line, some time or other, and knew what was what."

"H'sh! he's coming on again! Lie low, now; Andy!"

Accordingly both of them remained perfectly motionless as the professor advanced toward the house. Had he shown any disposition to head toward that particular corner Frank was ready to assume an attitude of indifference and appear to be engaged in some boyish game with his jack knife, tossing it up in the air, and causing the point of the long blade to stick upright in the ground.

But the small man with the brown glasses and the butterfly net made straight for the front porch of the house, and passed in at the door, just as though he felt perfectly at home there.

"Well, what next?" remarked Andy.

For reply the other beckoned, and started hurriedly to gain the shelter of the woodshed near by.

"What's this for?" questioned Andy, when they were once more crouched down, in a position where they could not be easily seen.

"Stop and think," answered the other; "if he just happened to look out of a window on this side of the house he'd see us easily and our suspicious actions would tell him we were on to his game. Now even if he looks he won't see anything."

"Huh! and do we stay here all afternoon just doing nothing; while p'raps he's taking a nap indoors?" grumbled the other, who wanted to be moving, and was never satisfied when not in action.

"Wait!" was all Frank would say.

Perhaps he could see further ahead than his cousin, and guessed something of what was likely to occur. They had not taken pains to warn Sallie or her mother to keep from mentioning the fact of their happening around; and chances were, that as soon as Casper Blue heard that the Bird boys had dropped in, he would become immediately suspicious.

On questioning the girl he would be apt to learn how curious Frank and Andy had seemed about him; and Sallie might even admit that they had asked to see his wonderful collection of rare and costly butterflies.

Well, if such a thing did occur, of course the keen-witted man would immediately know that the cat was out of the bag. Realizing that there must be a great hue and cry throughout the entire county just then, with reference to the yeggs who had looted the bank, he could easily imagine what had brought these boys here.

Through association with Todd Pemberton, Casper must have learned a whole lot with regard to Frank and his cousin. Being an aviator himself he would naturally take an immediate interest in boys who had given such a good account of themselves in the field of aeronautics. The attempt to steal the hydroplane in the first place before they turned to Percy Carberry's biplane proved that they knew all about the Bird boys. And so, learning of their presence would immediately give Casper warning that his hideout was no longer a secret, but that the net of the law must be closing around him.

What then?

Would he, like a desperate man, attempt to capture these venturesome lads, so as to keep them from informing the authorities at Bloomsbury? Either that, or else he would think that, since the game was up, and they could no longer loiter in the neighborhood of the aroused district in order to carry out the second part of the great scheme, they had better take to the aeroplane and vanish from view, leaving no trail behind by means of which they could be followed.

Frank had said all this in his mind when he lay there and waited to see what would turn up. He felt that they could surely afford to linger for some time, if there was any chance of learning whether the yeggmen meant to change their plans, or proceed to carry out their original scheme.

All seemed quiet at the farmhouse.

Sallie had come out on the porch, and looked rather disappointed to find that the two boys had strangely vanished. She stood there glancing around in a puzzled manner for several minutes, and then with a pretty shrug of her shoulders, and a pout of her lips whirled about and went back into the house again.

"Wow!" said Andy in a low tone, "she's got it in for you, Frank, because you dropped out of sight without even so much as saying goodbye."

But the other was thinking of weightier matters than the humor of a little coquette. He wondered whether Sallie would run across the professor and ask him if he had met two boys down the lane; which remark would excite his suspicions, and lead to other questions, now on his part.

If nothing happened inside of half an hour. Frank was of a mind to try the plan that had come to him—sending Andy off to try and reach some other farm where they would have a telephone; while he himself remained to keep watch.

That might necessitate taking Sallie into their confidence, for they would need to ask questions, and perhaps borrow a horse. On second thought Frank was now a little sorry he had not seen fit to tell the girl all. She seemed to be fairly clever, and could possibly keep a secret. At any rate, the chances of discovery would not be nearly so serious as now, when in her ignorance she was likely to blurt out all about the boys having been there, without knowing that in so doing she might be assisting clever yeggmen to avoid arrest.

The seconds moved along and changed into minutes.

If the professor had come to a window on that side of the house to look anxiously around, he must have been careful not to expose himself, for though Frank had kept a keen lookout he had failed to see anything of him.

It was getting very much of a bore to Andy. He changed his position restlessly several times, as though he wished Frank would make some sort of a move, he hardly cared what its nature so long as it meant action.

But although Andy could not see it at that moment, there were lively enough times ahead of them to please even his impetuous nature. And the passage of every minute brought the crisis closer and closer.

Once Frank believed he heard loud voices inside the farmhouse; and at the same time some one was certainly hurrying back and forth. But then possibly that might be only Sallie, obeying another call from the kitchen, where the good woman was so busily engaged with her canning operations.

Something like twenty minutes must have passed since the boys made their change of base. To Andy it was much longer, for he felt the time pass as though it had leaden wings.

Then Frank, watching, saw some one come hastily out of the front door, pass quickly down to the path, and move away in the direction of the lane.

"He's going off, Frank!" exclaimed Andy, all excitement, just as though he half expected that his companion would give the word that meant an immediate pursuit.

"Yes; keep quiet, Andy!"

"But he'll give us the slip, don't you see?" persisted the other.

"Let him, then; we can't help it. You can see that he's made quite a change in his looks, as though he's thrown the mask off, and doesn't expect to play the part of a collegeman and a bug collector any more," Frank whispered.

"That's so, he hasn't got the brown glasses on, and that old butterfly net is missing; but Frank, just notice, won't you, how he hangs to that little camera-like black box. Say, perhaps I was right after all; perhaps Casper Blue is carrying all that stuff cribbed from the Bloomsbury bank, inside the same."

The two boys crouched there behind the woodshed and by cautiously peeping around the corner could watch the late boarder of the Hoskins hurrying down the lane, as though he had received a hasty summons from the president of his college demanding an immediate return.

He seemed uneasy and suspicious, for several times he turned his head and looked this way and that, as though half expecting to discover some person ready to dispute his departure. And Frank also noted the way one of his hands had of keeping in the pocket of his short coat; just for all the world as though he might be grasping some sort of pistol that was concealed there.



CHAPTER XVII

SALLIE RIDES BAREBACK

"And now what's our next move?" demanded Andy, who generally found it very nice to let Frank do all the planning, though capable of taking hold himself when forced to do it.

Fortunately Frank had a great way of figuring out what he would do under certain conditions. This gave some sort of assurance when difficulties arose; for there was little time lost in fixing things up so as to have a programme.

"No use trying to follow after him, to begin with," he declared.

"Why do you say that?" his cousin wanted to know.

"First of all, it would be a bad business, because he's on his guard, and a desperate man," Frank went on to explain. "You can see that he's ready to pull out a weapon of some sort at the first warning. And we settled that we didn't want to fall into the hands of these two bad men. So we'll have to arrange things along a different line. And anyhow there's no terrible hurry, because I rather guess they've got the biplane hidden some distance away from here. It would take half an hour, perhaps much more, before they could get out. And we can reach our craft in a few minutes, if pushed."

"Yes, that's all so, Frank; but go on, and tell me the rest."

"I was thinking that we ought to try and let our folks know how things are going with us, so that if we have to cut out after these yegg aviators they'll know where we've gone. Suppose, now, you hunt Sallie up, and try to explain it all to her just as fast as you can."

"Who, me? Oh! well, I guess I can do it, if I have to. But what will you be doing all that time, Frank?"

"I want to write a message to either your father, or else Judge Lawson, whichever she can get on the phone," replied the other, immediately hunting in his pockets for pencil and paper, which he made it a habit to carry around with him always.

"She—say, do you mean Sallie, Frank?"

"No other. You must coax her to saddle up a horse, and make for the nearest neighbor where they've got a phone; get that, Andy?"

"But do you think she will?" asked the other, dubiously.

"I'm dead sure of it," came the confident reply. "Sallie has a touch of romance in her make-up; and besides, shell be so mad to think of that man deceiving her mother that she'll want to have him caught. Get along with you, now, Andy, and fix it all up inside of ten minutes. I'll have the message written out by that time, so she can start, if there's such a thing as any kind of a horse around this wreck of a farm."

And so Andy, glad at least to have something to do, hurried toward the house to look for the country girl.

Left alone, Frank continued to write as plainly as he could what he wanted those in Bloomsbury to know about matters in general. He used as few words to cover the case as possible, but gave the leading points, even to stating his fear that the scoundrels who had robbed the bank, and were plotting to also make a descent on the pay-car of the railroad that night, had now taken the alarm, and would be off in the stolen biplane.

In that event Frank wanted the police in Bloomsbury to know that he and Andy had started in pursuit; though what they could do to apprehend the rogues of course he was in no position to declare.

By the time he had this finished to his satisfaction he heard voices near by, and was glad to see his cousin coming, accompanied by Sallie.

The girl looked duly excited, just as Frank had expected. There were a thousand questions in her eyes, but he cut all this short.

"We can't stop to tell you any more now, Sallie, but we promise to drop in again after it's over, and explain all that seems queer to you now. Here's the message that we want to get to Bloomsbury the worst kind, and as quick as you could get on a horse and ride to the nearest neighbor who has a phone in the house. You'll do this for us, won't you, Sallie?"

Few people could say no to Frank once he wore that winning smile, and Sallie immediately declared that she was ready to do anything he suggested.

"To think of that little scoundrel fooling us all, and pretending to be a college professor!" she remarked, indignation flashing from her black eyes.

"I hope you've got a horse," said Frank, sticking to the business in hand.

"Oh! yes; we have one left that might do," Sallie answered.

"Then let's get him saddled right away," Frank went on.

"Can't," she snapped back, "ain't such a thing as a saddle around here any more. But I'm a country girl, you know, and I can ride bareback all right. A halter's the only bridle I want, Frank. Give me the message, and I'll see that it gets to somebody in Bloomsbury."

"And here's some money, Sallie," the other went on.

"What! do you think—"

"There might be something to pay, you know, and we can't afford to take chances when there's so much at stake. Thank you a thousand times for helping us out, Sallie. Now, please get the horse. I'd like to see you started before we pull out, because we may have to chase after these fellows in our aeroplane, if they take a notion to fly away."

The girl hastened to lead the way into the stable where they did find an apology for a horse, which she immediately unhitched, and led outside.

"Hope she doesn't happen to run across that man on the way, because he might wonder what was taking her off like that, and do something to turn her back. What if he found your message on her, Frank?" and Andy, as he said this, turned an anxious gaze upon his cousin.

But Frank shook his head.

"I saw him dodge out of the lane and take to the woods," he remarked, "as though he knew of a short-cut across lots to the place where his friend and the biplane were hidden. No danger of his seeing Sallie, so don't mention it to her. Wait, I'll give you my hand to help you up, Sallie!"

But the country girl had led the horse alongside the drinking trough, and was on his back in a jiffy, long before Frank could come across.

"Goodbye, and good luck, boys!" she called back, as she gave the horse a switch with the end of the halter, and was off at a lumbering pace.

They stood there a minute or so watching the girl flying down the lane. She turned around once, and waved her hand at them, while her long hair blew behind in a cloud. Frank would not soon forget the sight of Sallie Hoskins going to carry the news to a point where it could be telephoned in to town—news that would cause a tremendous wave of excitement to pass over the whole of Bloomsbury.

"Hurrah! that's done, and well done too, Frank, I say!" exclaimed Andy, turning on his cousin with a face that plainly said, "What's next on our programme?"

"Before we pull out I guess we owe it to the good woman to tell her something of the truth, for I don't believe she knows a single thing about it from Sallie or the professor. So come along to the kitchen with me, Andy. Then we'll chase off to where we left our aeroplane, and stand ready for anything that may happen."

The two of them quickly reached the kitchen door. Inside they found Mrs. Hoskins, tired looking and red of face, still busily engaged with her canning operations; for peaches were ripe, and tomatoes needing immediate attention if she hoped to lay away her customary stock for the coming winter.

She came to the door where it was cooler, a look of rising curiosity on her patient face. And Frank started in to tell what he thought necessary. She was at first much worried to learn that she had been innocently harboring a criminal under her humble roof; but Frank soon allayed her fears on that account.

He also told her how Sallie had consented to ride over to a neighbor to send a telephone message for him, so that the good woman might not be worried over her absence.

And now, having done what he considered his duty, Frank began to think it might be the part of wisdom for himself and his cousin to consider their own affairs, and make for the spot where their hydro-aeroplane lay in the field.

"Oh! I do hope they are caught," said the farmer's wife. "Just to think of that easy talking little man being a desperate criminal! I shall be afraid to stay all alone in the house after this."

"Listen, Frank; somebody's shouting out there. What if both of those yeggs are coming back to get us?"

Andy had clutched the sleeve of his cousin's coat when saying this; but Frank did not need to be told that something like excitement was bearing down upon them.

"Oh! it's Jerry, my husband!" exclaimed Mrs. Hoskins just then, "and he seems to be dreadfully excited, too. Listen to him calling to me! I wonder what could have happened. What if he's gone and cut himself badly, always digging and making holes in the ground, since that silly old fortune teller said he would find a mine on the farm. And here he comes too!"

Just then a figure came staggering around the corner of the house. It was the old farmer, plainly tremendously excited, and although weak and almost out of breath from running, trying to tell her something.

"It's there, Jennie—found it, wife—ain't had all my work for nothin' I tell you! A vein of hard coal, think, enough to make us all rich! D'ye hear that, Jennie, girl, rich! Gimme a drink of water, for I'm nigh dead from runnin' to tell you the great news. Who's these boys, wife? Where's Sallie at?"

Frank would have liked very much to remain and hear the particulars of the farmer's good luck in locating a vein of coal on his property; but time would not permit. He only hoped Hoskins was not mistaken, for traces of coal had been known to exist around that neighborhood for some time, though up to now none had been found in paying quantities for mining purposes.

"Come on, Andy, we'll have to be skipping out. Please tell your husband all you know about what's happened, Mrs. Hoskins. Hope you have struck it rich, sir."

With that Frank hurried off, Andy trailing behind. The farmer stared after them as though hardly knowing what to make of it all; but they could hear the good woman begin to explain, and had no doubt she would be able to satisfy his reasonable curiosity.

For the time being the Bird boys must forget all about what lay in the past, because it was the future that should interest them wholly. They had reached a point in the hunt where perhaps a sudden change of plans would be necessary; particularly if those they followed had taken the alarm, and were ready to shake the dust of this section of the country from their shoes.

Away from the farmhouse hurried the two young aviators, making as near a bee line for the field where they had left their aeroplane as they could possibly manage, and all the while searching the sky for signs of the other flying machine.



CHAPTER XVIII

AN AEROPLANE CHASE

"Here it is, and everything seems all right!" remarked Andy as they reached the field, and found the hydro-aeroplane just where they had left it.

"Yes, no one has disturbed a thing, which I think is lucky for us," Frank went on to say, as he proceeded to put back the small part he had taken away with him, and thus place the machine in perfect condition for business.

Andy moved about, looking to see that all obstacles threatening to interfere with a successful launching were removed from in front of the waiting aeroplane.

So minutes passed, until at least ten had crept by since their coming. Frank had everything tuned up, and knew of not the least chance where he could improve the conditions of planes or motor, for all seemed to be as nearly perfect as they could be made.

Both boys cast frequent glances aloft, and as a rule toward that particular quarter where they presently expected to see something moving. They were keyed up to a pretty lively pitch of excitement, though Frank did not show it half as much as his younger cousin, who was always affected this way.

Then suddenly Andy called out:

"There she rises, Frank! Oh! look at them boring up, will you, in that corkscrew spiral way! Tell me that Casper Blue doesn't know his business; Perc will never get as much out of his biplane as that old and experienced aviator means to. Are we going to follow suit, Frank?"

"Get aboard!" came the prompt answer; and it was almost laughable to see how nimbly Andy obeyed this order.

Frank lost no time in starting, and they went away with a rush, passing over the abandoned field that was now given up pretty much to thistles and burdocks, with a sprinkling of iron-weeds.

It was rather rough sledding, to be sure, and as the bicycle wheels pounded over the turf the boys had to hold on to keep their seats.

But when sufficient momentum had been acquired, Frank elevated the fore plane, and immediately there was the greatest relief felt; for they began to rise in the air, and all that terrible bumping stopped for good. The change was wonderful, and it felt as though they were gliding on velvet.

"We're off!" exclaimed Andy, exultantly.

Frank said nothing. He did not possess quite the same sanguine nature that his cousin had. Andy seldom allowed thoughts of possible disaster to annoy him, but on the other hand Frank was always trying to head off trouble.

He realized that with this launching of their new hydro-aeroplane they would be entering upon an extra hazardous game, the outcome of which no one could foresee. The two men whom they expected to follow must be desperate fellows, who would resort to almost any hazard rather than allow themselves to be caught.

And it was not an amateur aviator like Percy Carberry who was opposed to them now, but one who had had long experience in the art of harnessing a flying machine to do his bidding.

Once they left the ground behind them, Frank started to spiral upward much in the same way the others had done. One thing he was glad of, and this was the presence of Andy alongside. Casper Blue might be a daring air pilot, but with his companion a perfect greenhorn in all that pertained to the art, he would be more or less handicapped. A sudden incautious movement on the part of the novice might prove the undoing of the precious pair.

Once they had risen to a certain height, and the aeroplane was turned so as to follow the other air craft, which was speeding away, headed directly into the north. Of course, those aboard must know that they were being chased. They could not have failed to see the hydroplane, (as it is generally called, though the true word to cover it would be hydro-aeroplane) even before it left the field, once they started to ascend.

"Well, we're off at last!" commented Andy, in a satisfied tone, when the course had been taken, and they were following directly after the fugitive air craft.

"And let's hope we'll come out of this adventure as luckily as we have on other occasions," remarked sober Frank.

"Wonder if Perc happens to be looking this way right now," Andy went on to say. "Chances are, that he's got his old field glass leveled, and is searching the heavens right along, in hopes of locating his lost machine. And say, if he does glimpse this fine parade right now, can't you see him turning green with envy to think of another glorious chance coming to the hated Bird boys. Oh! my, oh! me! but it would be gall and wormwood to Perc. Just as like as not he'd take a fit!"

But Frank was not giving any time to such thoughts as these. More serious affairs engaged his attention. When once he left the firm footing of the solid earth, and invaded the upper currents where up to lately man had never traveled, save in a drifting balloon, he always put levity aside, and paid strict attention to business.

The panorama below them was constantly changing, and the boys could not but admire the pictures thus presented to their gaze. No matter how often one may go up a thousand feet or more above the earth, it is next to impossible to weary of the wonderful scenes that keep passing constantly in review as the buzzing motor keeps carrying the aeroplane along over plain, valley, hills, forests, rivers, and villages or towns that chance to lie in the route.

To Andy it was all somewhat in the nature of a grand picnic, for his nature was not one to contemplate peril at a distance. Had he and Frank just come out for an hour's spin he could not have shown more delight, as they went whirling through space, with that rival flier a mile or two ahead.

"Do you think we're gaining on them?" asked Andy, after some time had elapsed, and the country below began to get unfamiliar, proving that they had now come beyond the range of any previous trip taken to the northward of Bloomsbury.

"I don't know for sure," replied his cousin. "Sometimes I think we are, and then again I'm a little in doubt. Suppose you get the glass out, and see what they're doing, Andy?"

"Well, I'm a great one, forgetting all about that bully marine glass." As he said this Andy hastened to feel for the article in question, which was always kept handy, because there never could be any telling when they might want to use it in a hurry.

"Go slow; no use rocking the boat," sang out the pilot, who was forever cautioning his companion with regard to quick motions when seated in such a delicately balanced contraption as a biplane. "It's a good thing that we've got that new fool-proof contrivance that Mr. Wright invented, on this machine right now, because only for that you'd be giving me more than a few scares when you swing from one side to the other so quickly."

A minute later, and Andy, who had been looking through the glasses, spoke again.

"It's a little hard to cover them steadily, because they keep rising and dipping just like we are; but I can see that little Casper Blue, and the man alongside of him is a much larger chap."

"Of course it's Casper who's piloting the biplane?" remarked Frank.

"Yes, and he knows the ropes, let me tell you. I don't believe there are many professional birdmen today who can go ahead of that man. I only wish you could take a squint through here, and watch how he manipulates the levers, in spite of that stiff arm of his. Only for that, and he'd still be in the harness, and doing stunts that'd have Beachy left far behind."

"Either that, or else he'd be buried," remarked Frank, drily.

"Oh! well, the less we have to say about that the better I'll feel, Frank. If you're going in for aviation at all you've just got to forget all about being in constant danger; though I hope I'll never get so I'll be reckless like Perc Carberry. But Frank, sure we seem to be picking up a little on that crowd. And from the way they keep looking back all the while, I guess they know it too."

"Perhaps we are," Frank went on to say, "but if I really thought so I'd cut down a peg or two in our speed."

At that Andy set up a howl; at least he voiced his objection.

"Well, that's a queer stunt for you to do, I must say, Frank. Here we are chasing after our game, and the very first time we believe we're gaining some, you inform me you mean to cut down our speed. Is that the way to win the game, tell me?"

"But we don't want to come up with them while we're booming along like this, you understand," ventured Frank, as he gently moved a lever just a trifle; "this sort of racing is a lot different from what you'd do on the ground down there. Suppose we did come abreast of that biplane right now, what good would that do us? Could we put out a hand and arrest the yeggmen? Wouldn't it be more likely that such desperate men as these must be, would try some sort of game looking to disable our craft, and sending us tumbling down to our death? No, excuse me from coming to close quarters up here with such hard cases. Honest now, Andy, if they began to circle around as if they meant to turn on us, I'd think it my duty to run!"

"Oh!" exclaimed Andy, "you mean you'd coax 'em to follow us back to Bloomsbury, and then give themselves up, is that it, Frank? Oh! but you're a cunning chap, sure you are. But on the level now, what is our game, if it doesn't mean we're going to overtake 'em?"

"I'll tell you, Andy. We ought to keep following after them as far as we can, and in that way learn where they drop. If we get a chance to send down an occasional message to be sent on to Bloomsbury so much the better. I've written several such out, and have the cord to tie them to weights. Given a chance, when we're passing over some town perhaps we can get one such message sent on home. Even that would tell them where we were, and what the chances are."

"Great game, Frank! Suppose you let me have those messages, and I'll be amusing myself getting the same ready to heave, when you say the word. We c'n play that this is a war game, and we've been sent out to drop bombs on the fortifications of the enemy. We've done it with rocks, and we can throw pretty straight; so it seems to me we ought to get some sort of fun out of it all around."

Frank told him where he could find the written messages in his outer pocket; and for some time Andy was quiet, busying himself in fastening some sort of anchor to each piece of paper, sufficient to carry it earthward, despite the breeze that at the time might be blowing.

All at once Andy noticed that they were going quite slowly in comparison with the pace they had lately been "hitting up."

"What's happening, Frank?" he exclaimed, almost alarmed lest some accident had befallen the reliable little motor, which up to now had never failed them, no matter how great the call upon its resources. "Why are we slowing up? Is there something gone wrong, and must we own up to being beaten?"

"Look ahead at the biplane!" was all that Frank replied.



CHAPTER XIX

DROPPING A "BOMB!"

"Oh! we've started to swoop down on them! Honest to goodness, I don't believe they're more 'n half as far ahead as they were, Frank!" cried Andy, thrilled by the sight of the other biplane being so near.

"Just about that," said Frank, quietly, the busy motor having decreased its merry hum, so that they could talk without raising their voices very much.

"Then you must have let out an extra kink, did you, Frank, when I was busy with my bombs?" demanded the other.

"Oh! no," came the answer, "the fact of the matter is, Andy, they have dropped off a lot of their speed, and that's how we covered space quicker."

"Something gone wrong with Percy's new Gnome engine, then, has it; and he blew his horn so about what wonders it was going to do? Huh!" and Andy chuckled in his boyish delight.

"No, I don't believe that is the reason they've slackened their speed, Andy."

"Trying to save gasolene, then?" pursued the other.

"Hardly that, either, Andy."

"Oh! now I see what you mean, Frank; the poor old greenhorn's got cold feet, and is making Casper slow down. He thinks that there's less chance of a tumble if the speed is reduced; just as if that could make any particular difference."

"I reckon you're away off yet," persisted Frank.

"Then, for goodness' sake won't you tell me what they have cut notches out of their speed for; because I'm all balled up, and blessed if I can think of another thing! Oh! look at that, Frank! Sure as anything I saw a puff of smoke then. There must be something the matter with their engine, and they're getting scared. I wouldn't be surprised a mite to see them settle right away, and try to land."

"Well, you saw smoke all right, and if you'd listened sharp, you'd have heard a sassy little bark at the same time, Andy."

"A what, Frank?"

"Call it a snarl, then. Take up your glasses, Andy, and look; while I drop out even a little more of our speed, so we'll fall back further."

Hardly had Andy clapped the glasses to his eyes than he gave vent to an exclamation of mingled amazement and alarm.

"That greenhorn is looking this way, Frank, and as sure as goodness he's pointing at us right now. Oh! he did something then, for I saw another puff of smoke, and it came right from his hand. Why, he's shooting at us, Frank! That must be a gun he's got in his hand, and he's trying to hit us! If our motor didn't keep up such a constant whirl we might have heard the whine of that lead when it went singing past us!"

"Yes, perhaps we might," Frank went on to say, composedly.

"But what can we do?" demanded the other, nervously.

"Nothing more than decrease our own speed as often as they do, and play the game of tag backwards. If they get going it too strong, why, just as I said before, I'll turn tail, and head back toward Bloomsbury, daring them to follow, which you can be sure they won't, because our town is a mighty unhealthy place just now for Casper Blue and his pal. There! he fired again."

"That makes three times he's tried it, Frank!"

"And I guess he can try the other three without doing us any damage, Andy."

"You believe that, do you?" asked the one spoken to.

"Sure thing," Frank replied positively. "Why, it would be one chance in ten thousand that he could strike any part of our aeroplane at that distance, going as both of us are, and with only a revolver. I'd be willing to let him blaze away all day, without being a bit afraid. But I'm bound that the two air crafts must keep at least this distance apart."

The man in the other airship did fire three more times, but without any success whatever. And as though the rival navigator realized that Frank's tactics would effectually prevent his coming into closer contact with the pursuing craft, he no longer tried to close in, but increasing his speed, was quickly about the old distance away.

Whereupon Frank Bird also hit up the pace cautiously.

"That's the ticket!" cried out Andy, presently. "I guess we're holding our own again now. For a little while I began to be afraid that they were going to just make us take their dust, and give us the merry ha-ha, vanishing in the distance. But now I know you've got the twist of the thing down fine, Frank, and can haul up on the biplane, or drop back, just as you feel like."

For a long time they kept on, neither saying anything, for talking is always more or less of an effort when speeding along in an aeroplane, with the wind striking one in the face.

Frank had had no time to fully adjust the muffler which he usually wore about his neck when about to soar to a dizzy height, so he would have to do the best he could; and besides, there was little chance of the other aeroplane venturing to bore upward to any unusual degree, all the efforts of the bank thieves being directed toward making their escape.

He did have his goggles adjusted, however, which was a good thing, since his eyes must have watered very much from the cold air; and this is considered an ever present source of danger to one who manipulates the levers of a mile-a-minute aeroplane.

"We seem to have dropped a good deal lower, Frank," remarked Andy, after another space of time had elapsed.

"Yes," remarked the pilot, tersely.

"And I'm looking now for a good chance to make use of one of my bombs; don't you think it's about time to try the scheme out?" Andy continued.

"Just as you feel like," replied Frank.

"Then at the very next town, or place that looks like it had telephone connection with the outside world, I'm going to have a try. Might have done it when we passed over that last place where the people were all waving things up at us, and we could just hear a confused shouting. I bet you, Frank, they just thought this was a regular air contest, with a prize offered to the winner."

"Well, it is," observed the other. "If we win, we take back our prisoners; and on the other hand, if they come out first best they get away to Canada with their liberty and their plunder. Yes, it's a race, all right, Andy, a test of skill and endurance; and perhaps the best man will win."

"Then I know who that will be," declared Andy, enthusiastically.

"Don't be too sure," warned Frank, though it must have pleased him to know that he possessed the fullest confidence of his cousin and chum, who had been his constant companion on so many expeditions, and must understand him like a book.

"What if they keep everlastingly at it, and night comes on?" asked Andy, presently.

"Well, there's the moon, though I don't like chasing along this way after sundown; and if we're put to it, we've got our fine search-light, you must remember," Frank replied.

"There, I believe we're going to pass right over another town, Frank!"

"It does look that way, for a fact," admitted the other. "Casper doesn't see any reason why he should bother changing his set course due north because he happens to pass a few towns away up here in the northern end of the State. Let the people stare all they want to. He's been used to having crowds gape at him, you know, and rather likes it. Besides, if he gets away, what does it matter?"

Andy prepared himself for the little job he had on hand.

As he had practiced throwing stones from the aeroplane while at a great height, just to see how near he could come to hitting a certain place far below, so as to ascertain what chance aviators would have of making bombs tell in war times, the boy believed he would be able to drop his message pretty accurately in some open place, close to where the townspeople were clustered. And seeing it fall, some one would be sure to hurry over to secure the mysterious object.

"Here goes our old broken wrench, which has been hanging around so long!" declared Andy, as, leaning carefully over, he measured distances with his eye, and suddenly let the object slip, taking care to make all allowances for their speed.

This is more of a trick than most boys would suppose. The next time you are on a speeding electric car throw a stone at a telegraph pole just as you are passing it, and see how much beyond the missile will alight, because of the momentum it received because of the fact of its starting from the moving car.

Andy had this pretty well figured out, and knew just when to launch his weighted message. He turned his head, and tried to follow it downward as well as he was able because of the fluttering white paper.

"It's going straight there, Frank, I do believe!" he exclaimed, as he managed to get the powerful glasses up to his eyes, and fairly followed the progress of the message, though quickly losing it again. "Yes, and the crowd there on the green must see it coming, because already a bunch of boys has started to jump that way. They'll find it easy enough, Frank. Now, what d'ye think of that for a successful bomb throw?"

"Good enough for you, Andy," was the hearty response. "And we'll have to take it as a sign that we're going to come out of this scrape as we generally do, with our colors flying."

Frank usually allowed himself to feel the fullest belief in his own abilities; at the same time he always wished to avoid over-confidence.

Again time passed on, and the hum of the busy motor was the only sound that came to the ears of the two young aviators. They were again making nearly full speed; though Andy felt pretty confident that, had it been necessary for Frank to coax an additional unit or two of "hurry" from the gallant little Kinkaid engine, it would respond to his efforts.

"My! but we must have covered a lot of distance since we started," was the next remark from Andy. "How long do you suppose we've been going, Frank?"

"Look and see. It was just five minutes after one when we left the field on the Hoskins farm, Andy."

"Two hours, Frank; now, what d'ye think of that? Why, I never would have believed it if you'd told me. Do you think my watch has jumped on ahead?

"No, because we've been hustling right along all of that time, I guess, Andy."

"Keeping everlastingly at it, and headed due north all the while," said Andy.

"As straight as a die; they never varied their course even a little bit, as far as I could see," the pilot declared.

"But we've covered an awful lot of apace, Frank!"

"I guess you're right there," admitted the one addressed.

"And, Frank, if we keep on this way, and nothing happens, we ought to sight the big lake away; ahead there inside of 'half an hour more, I should think?" Andy ventured to say, and he was thrilled when his companion, turning toward him just at that moment, went on to say:

"Perhaps in less time than that, Andy; with the glasses you might glimpse it even now!"



CHAPTER XX

OVER LAND AND SEA

"Are you joshing me, Frank?" demanded the other Bird boy, as he swung eagerly around, so as to fix his glasses upon the far off horizon ahead of them.

"I certainly am not, Andy; but please be more careful how you move. You gave me a punch in the ribs just then that sent a cold shiver all over me. Don't forget that we're not stretched out on the ground under an apple tree taking an afternoon doze. Well, what do you see?"

"Frank, I do believe you're right about that lake business!" exclaimed Andy.

"Then you can see it?" asked the other, himself more than anxious, because of the fact that the fleeing bank robbers who had stolen the biplane of Percy Carberry apparently intended to escape over the line into Canada, even if to accomplish their purpose they had to daringly cross Lake Ontario, many miles wide, a feat as yet only successfully done by one or two bold fliers of national repute.

"I sure can; and the way we're heading it's a dead open-and-shut thing that we're just going to swing out over the water before another hour passes. Whew!"

Andy finished his sentence with this significant exclamation. It was as though not only the novelty of the thing but its thrilling nature staggered him. The Bird boys had flown under many strange conditions, but as yet they had not made a water flight.

There is and always must be a vast difference between passing over the land, with its forests, hills, valleys, plains, cities and villages, to starting out over a wide stretch of inland sea, with only the tumbling waves far below, and new as well as untried currents of air to meet and conquer.

More than a few times Andy Bird had expressed a wish to have just such an experience. It would be a novelty, something entirely new in their line, and which would give them possibly delightful thrills.

But now that the chance seemed opening up before them, he found himself viewing it with considerable apprehension, as well as delight.

Of course it made considerable difference that they should be chasing after a desperate pair of rascals, rather than simply trying to accomplish a flight from United States territory to that belonging to Canada. There was always the chance that these men might turn upon them, and succeed in doing something to injure the hydroplane, causing it to drop into the midst of that inland sea.

Strange how small things often insist upon thrusting themselves forward when some sort of peril threatens. The very first thing Andy seemed to think about was the fact that they did not happen to have any life preservers aboard the craft. Not that there was one chance in a thousand they would ever need such things around Bloomsbury, though there was Lake Sunrise to be reckoned with; but just then it struck the boy that every well equipped aeroplane ought always to carry a couple of rubber rings along, which, in moments of dire necessity could be blown full of air, and would serve to sustain wrecked aviators until help came.

He even decided to mention this fact to his cousin, after this voyage was concluded. It loomed up as large as the Rock of Gibralter just then, even as a dream may at the moment of awaking, but which later on begins to lose its realistic effect until it seems next door to silly.

"They don't show the least sign of changing their course, do they, Frank?" Andy remarked after another spell of time had passed.

"Not that you could notice," replied the other, composedly.

Andy derived more or less comfort from this way his chum had of keeping his head even under the most trying conditions. When his own nerves were fairly quivering with excitement, it always steadied Andy to turn and see that Frank was as cool and calm as though nothing were amiss. More than a few times in the past it had caused the more hot-headed Bird boy to conquer his own weakness, and do himself credit in some difficult feat that became necessary. Example is a splendid thing to lead any boy along safe roads. Words may be forgotten in the trying moment; but when he actually sees the thing done before his very eyes, it is indelibly impressed upon his mind.

"About how long will it be before we get there?" Andy asked again; for he was forever wanting to know, when he had any misgivings about his own capacity for reaching a reasonable conclusion.

"Do you mean before we leave the land, and commence our voyage across the lake?" Frank inquired.

"Yes, that's it—more than half an hour, at the speed we're going now?" continued the other.

"Just about, I should say," Frank replied, after carefully measuring distances with his eye. "We are up pretty high, and can cover a tremendous range, you know, so we first glimpsed the lake when we were a long ways off. It may be all of forty miles away right now; and as we must be clipping along at the rate of eighty, with the breeze favorable behind us, why, half an hour ought to see us there."

Andy fell silent again.

Many times did his eyes travel from the distant water to the earth below them; and then follow this up with an uneasy stare at the other aeroplane that was flying along far ahead of them. The whole solution of the problem of course lay in the hands of the man who controlled the destinies of that stolen biplane. Would he really have the nerve to attempt a flight across that great body of fresh water, aiming to land on foreign shores, from which he could not easily be extradited?

Frank seemed to think that such was undoubtedly the intention of Casper Blue, the little man who had been actor, aviator, and yeggman in turn, during the course of his adventurous life.

He had already proven beyond any doubt that he was a capable airman, even though he did have a crippled arm. Never had the Bird boys seen an aeroplane handled with more extraordinary skill and dash than was the one that had been stolen from the hangar of Percy Carberry.

No, unless something unexpected happened to disturb the plans of the fugitive yeggmen inside the next half hour, they plainly meant to launch out on a voyage across the lake, possibly thousands of feet above its surface, and perhaps among the very clouds.

Not once did Andy dream of asking his cousin whether in this event he considered it the part of wisdom for them to follow the men who were doubly risking their lives in this mad effort to escape with their booty.

He knew Frank only too well to doubt his willingness to undertake such a trip as this. In times gone by, and especially when they were down in South America with their aeroplane, seeking Professor Bird, who had been lost, with the balloon in which he was conducting experiments on the isthmus, they had bravely faced just as serious perils as this promised to be; yes, and wrenched victory from the jaws of apparent defeat more than once.

Hence, it was a foregone conclusion that if Casper Blue attempted the difficult feat of flying across the lake, after being in the air several long hours, the two Bird boys were determined to keep following after him. It seemed like a game of "conquer," which Andy remembered so well; where the rival aviator dared to go they must follow, or acknowledge his superiority as a bold airman, something neither of them felt like doing.

Frank had figured it all out while he was speeding along so smoothly.

So far as he could see everything was working as easily as could be; the motor never missed, and was running like a charm, just as though it could keep this up everlastingly in an endurance test. And besides, the wind, what there was of it at present, seemed to favor them most positively, because it was at their backs.

So far as appearances went the conditions were ideal for the crossing of the great lake that was now showing up ahead most grandly.

Andy drew in big breaths, and tried to keep from quivering with delight, mingled with just a little nervousness. Here was a new experience about to come to them; and one that they were not apt to soon forget. As a boy Andy delighted in novel sensations; and as an ambitious aviator he yearned to experience all the glorious possibilities that open up to the one who has the pluck and the nerve to attempt them.

They could see a town in plain sight, though they had gradually ascended since Andy cast his bomb so successfully. Perhaps his little game of opening communications with the earth below had been observed by one of those in the leading airship; and in order to prevent another attempt, this gradual ascent had been immediately carried out.

But Frank fully expected to see the rival aeroplane begin to drop as they drew near the border of the fresh water sea. Since just then there was no squally wind near the surface of the water, which they wished to avoid by remaining thousands of feet high, the chances were that Casper Blue would soon commence to use his deflecting rudder, and begin to descend in wide spirals; or else, with the daring of an old and skilled air navigator, shut off power, and volplane down in a slant that would thrill any spectator as nothing else could, until the required distance had been covered, when he would again bring the shooting aeroplane on a level basis, and resume his forward progress.

Whatever he did Frank was ready to imitate.

He had the fullest confidence in his own ability to accomplish the most difficult feat that would be required.

"Steady yourself, now, Andy," he cautioned; "because they're going to change the going pretty soon, I take it. Better put that glass away, and be ready to give me a lift if I need it. Watch and see if they don't drop down closer to the water. It would be a wise thing to do, I take it; for in case of accident the spill wouldn't be so bad."

"All right, Frank, just as you say," replied the other, accustomed to looking to his cousin for the words of command when an emergency or a crisis came along.

He fastened the precious glasses in their rigid case, where they would be safe so long as the aeroplane remained above the surface of the water, or did not fall to the ground in a serious wreck.

Then Andy paid attention to a number of small but very important matters that had always been given over into his charge at times like this. The Bird boys had been comrades so long that they worked together like a well oiled machine. The ball team that has played in company for a season can accomplish feats that would be utterly impossible to a nine that had been brought from various clubs, even though each player might have been a star in his respective team.

So it was with Frank and Andy; they had grown to know each other's points so well that when the moment came it often seemed as though they instinctively formed a single unit, with that exceedingly bright brain possessed by Frank doing all the piloting of the combination.

They were all ready for the business in hand long before the border of the big water was reached. Frank had looked around him several times, and his cousin seemed to know instinctively that he was endeavoring to decide as to whether the wind was apt to hold as it chanced to be at the time; or increase in velocity, should they drop to lower levels.

It was rather awe inspiring to see that vast gulf of glistening water stretching as far as the eye could reach in three directions, north, east and west. From the high altitude which they still occupied, they could not tell whether the lake was calm, or waves rolling along its surface. The westering sun glittered from its bosom as though it might be streaked with gold, and altogether it was a sight that neither of the boys would soon forget.

To Andy in particular it appealed with vigor. His nature was more inclined to worship at the shrine of the romantic than would be the case with the practical Frank. To Andy that vast sheet of water seemed mysterious, profound, filled with secrets of argosies that were launched on its breast centuries ago, when only the bark canoes of the red men had ever been wedded to its waters. In imagination the boy could even then see the barques of the early explorers, those bold men who had pushed thither from across the ocean, and risked their lives in order to learn what the New Country held for brave hearts.

Perhaps, had he still gripped the glass in his hands, and cared to look earthward before leaving the shore for that adventurous cruise, Andy might have seen many a group of wondering people all watching the flight of those hurrying ships of the upper air currents, and even waving hats and handkerchiefs in the endeavor to attract the attention of the bold navigators, whom they supposed to be engaged in a race for a wager.

But there was now no longer time for anything like this, and all their attention must be concentrated upon the one thing that meant so much to them—the safety of the delicate craft in which they were now about to entrust their very lives for a voyage, the like of which few airmen had ever entered before.

Already had the other aeroplane sailed away, and was even now hanging over the inland sea, that lay fully four thousand feet below, its further shore hidden in what seemed to be a cloud, though it might prove to be a rising fog, fated to engulf both pursuing and pursued air craft in its baffling folds, and turn the comedy of the race into a tragedy.

"Goodbye old land!" sang out Andy, when they seemed to suddenly pass out over the water, leaving the shore of New York behind.

Frank said not a word, but no doubt his feelings were just as strong as those of his companion. And so they had now embarked on what seemed to be the last leg of the strange chase, with the future lying before them as mystifying as that fog bank lying far away to the north.



CHAPTER XXI

OVER THE BOUNDARY LINE

It was with the queerest possible feeling that Andy saw the land slipping away, and realized that they were at last launched upon the water part of the voyage.

It seemed as though they had cast loose from their safe moorings, and were adrift upon an uncharted sea. When comparing his feelings with other aviators in later times, he learned that every one of them had experienced exactly similar sensations the first time they passed out of touch of land, and found the heaving sea alone beneath them. It was a sort of air intoxication; Andy even called it sea-sickness, though doubtless most of it came from imagination alone.

"There they go, Frank!" he called out, not ten minutes later.

The land was far behind them now, and still in the other three directions they saw only the level surface of the great lake.

His exclamation was called out by a sudden change in the method of advance adopted by those in the leading aeroplane. Instead of keeping along in a direct line the biplane had uptilted and was now shooting downward in what seemed a terribly perilous way; just as though the pair of precious scoundrels had taken a notion to end the pursuit by seeking a plunge into the water.

But both boys knew differently, and that this was only a volplane, adopted by experienced and rash aviators as a means of reaching the lower air currents more rapidly than by slow spirals; or else undertaken when having engine trouble that threatens destruction.

Frank was ready to follow suit. It would not be the first time by long odds that the Bird boys had accomplished this speedy method of descending from high altitudes. There was always an exhilaration about the clever trick that appealed irresistibly to their natures; though Frank would never have attempted it unless reasonably sure that the conditions were favorable for success.

"Hold fast, Andy!" he remarked, quietly.

The hum of the motor suddenly ceased, and with its cessation the hydroplane was turned head-on toward the surface of the lake, four thousand feet below.

Down they went, plunging toward what seemed to be instant destruction; but a steady hand was at the wheel, and the pilot knew just what was necessary to do at the proper instant in order to bring this rapid descent to a stop, and right the airship on a level keel.

But there was no time just then to note what the rival aeroplane might be doing. Whether the experienced airman in charge managed to stop that downward plunge before reaching the surface of the lake; or failing went to his death, was a matter that did not concern them now, since they had their own affairs to look after.

To tell the truth, Andy's heart seemed to be in his throat as they made the drop. As yet they had never tried out the new hydroplane in a trick of this sort; and hence really did not know just how it might act; though Frank must have been pretty confident, else he would never have attempted it.

Given the choice the Bird boys would easily have decided to descend from their lofty height by means of the much safer if slower "spirals," each circle seeing the aeroplane lower than before. But since the reckless man in the other air craft led the way, Frank had chosen to follow. He believed that he could accomplish any feat that was possible to Casper Blue, especially now that the old air navigator had a handicap in the way of a crippled arm.

The water seemed rushing up to meet them; so it looked to Andy, whose anxious gaze was fastened upon the lower depths, as they dipped down in that terrific swoop. But then, he had seen the same thing when over the land, so that in itself this did not daunt him.

"Oh!"

That exclamation seemed to be forced from Andy's lips when he felt Frank give a quick turn to the lever that caused the deflecting rudder to again resume a normal position. The drop of the aeroplane was brought to a gradual stop, and when immediately afterwards the buzz of the motor announced that the propelling power was again at work, it was no wonder that the nervous boy expressed his relief by giving vent to that cry. There was a world of gratitude back of that word, it can be set down as certain; for no matter how confident Andy might have been concerning his cousin's ability to accomplish wonders, the new hydroplane was as yet untried in many things.

Now he even dared take his awed gaze from the heaving waters beneath the framework of the aeroplane, and give a thought to those whom they had chased overland and water for nearly three hours.

"Bully for Casper Blue! He made the riffle too! he's all to the good!" was the way the impulsive Andy announced his discovery to Frank, who just then could not spare even a second to take his attention off the working of the motor.

After all, it was not so very strange that the boy should express himself in this way. True, the man he was praising was now a criminal, and they sought to effect his arrest in some manner as yet vague and uncertain; but it was not in this light Andy viewed him just then. As a birdsman Casper Blue had proved that he still possessed the nerve and skill to direct a daring flight, and that all the tricks known to celebrated fliers were at his finger's ends.

Any one who has risked his life up among the clouds must always respect such a valiant spirit, even though aware that the object of his admiration has in other ways forfeited the esteem of all honorable men.

There was the biplane moving along on a level keel, and not more than two hundred feet above the water. And still the course held due north, showing that the desperate men who were thus fleeing from arrest had not the slightest intention of changing their plans.

"What do you think of her now, Andy?" asked the pilot, with a quiver of pride in his voice.

"You must mean our new craft, I take it, Frank; and I want to say that she's a real peach, if ever there was one. We never volplaned as easy as that in our lives, and that's a fact. Why, it was like sliding downhill on a sled, with never a single bump on the way. I could do that all day, and never get enough."

"Dangerous business, all the same," remarked Frank; "and doubly so when you don't happen to be well acquainted with your machine. A single hitch, and we would have struck the water at a terrible rate."

"But all the same we didn't, Frank," the other went on, jubilantly; for now that this peril was of the past Andy could be his old self again.

"And they did just as well," remarked Frank, always ready to give credit, even though it might be to a rival, for his nature was generous to a fault.

"Well, that biplane was easier to manage than our hydroplane, with the pontoons underneath," Andy went on to say, grudgingly; for no one could ever convince him that Frank had his superior as an air pilot; and he would sooner go up to a record height of fifteen thousand feet in company with his cousin, than accompany the most famous man living.

"It looks like we might be booked for Canada, Frank," he went on to say, a minute later, after they had fallen into the new "stride" comfortably, and were rushing forward on a level stretch, with the surface of the lake close at hand.

"I shouldn't wonder," came the noncommital reply.

Now, Andy knew his cousin like a book. Perhaps it was something in the words; or on the other hand there may have been an undercurrent of doubt in the way Frank spoke, that aroused the other's suspicion.

"What is it, Frank?" he demanded, "for I reckon you see something that is all a blank to me? Take me in, won't you?"

"Oh! I was wondering what would happen if they had an accident away out on the lake, that's all," admitted the other.

"Well, in that event I guess it'd be up to the Bird boys to play the rescuer act for all it was worth. But Frank, do you think this new machine of ours could climb up off the water with four aboard? Wouldn't that be the limit?"

"To tell you the truth, Andy, I don't know, because we've never had the chance to try it out. With only two of us aboard you know how easy she climbed; three passengers she could hoist, but four might faze her. We can only wait and see, if ever the chance comes to make the test."

"But you wouldn't hesitate about trying the same, I know, Frank?"

"Of course not," the other remarked, confidently, "and especially when it might mean life or death to a poor fellow away out here on the lake miles from land. If we couldn't rise, we might still be able to float like a duck, and hope that some boat would come to the rescue. In the end that would be just the same."

"Do you know," said Andy, "I saw a tug pulling out at full speed from the little city on the shore of the lake, close to where we left land; and somehow I seem to have an idea they know all about us, and mean to keep in touch with us as long as they can, to be handy in case of accident. Perhaps, now, my message was phoned to Bloomsbury; and seeing about where we must be heading if we kept on a northerly course, they have wired up here to watch out for us. How about that, Frank; am I silly to figure that way?"

"I don't see why you should be, Andy. In fact, just as soon as you mentioned about the tug I began wondering if somehow these good people didn't know who we were, and what we were chasing after the biplane for."

They had to speak unusually loud in order to hear, even though their heads were close together at the time; for the propellers were whirling with a hiss, and the hum of the motor added to the noise. But then, it was all a merry racket that chimed in well with the spirit of the young aviators; and which gave them much the same pleasure that the splash through the foaming water of a ninety-foot racing yacht must awaken in the heart of an enthusiastic skipper, when he knows that every sail is drawing to the limit, and all things are working well.

"Have you figured out what we ought to do if by good luck we all get over to the other side, safe and sound?" went on Andy.

"We'll have to leave that," was the reply Frank made. "No use crossing a bridge till you come to it, you know, Andy."

"But they'll be safe then, Frank?" "I'm afraid so, even if I don't pretend to be up in all the international law connected with the passing of a thief from United States territory to Canada."

"But ain't that a measly shame?" ejaculated the indignant Andy, "to think of a robber being able to turn, and put his fingers to his nose and wiggle 'em at us, just because he happens to cross the boundary line. It oughtn't to be that way, Frank!"

"Of course not; and I guess lots of abler chaps than you and me have thought the same; but there it stands, and the two countries won't get together to change the law even a little bit. Every year dozens of embezzlers light out across the border for Canada, where they can spend their money, and start for Europe if they feel like it."

"Then perhaps it's the money they take with 'em that the Canadians like; though I wouldn't like to believe such a thing," ventured Andy.

"Hardly that; but both countries are jealous about bringing back political offenders, I've heard Judge Lawson say more than once. But don't let's talk any more'n we can help, Andy. We've got our hands full as it is watching those fellows, and keeping ready to match any trick they try."

This served to give Andy a new cause for concentrating his attention on the fleeing biplane once more. As yet the pilot of the leading airship had not diverted from his set course; but if he was as tricky as they had reason to believe, there was always a chance that he might engineer some scheme, sooner or later, looking to shaking off his pursuers here in the middle of the great lake, where possibly no mortal eye could witness the deed, so as to appear against him later on.

With the wind aft, of course the further they advanced the larger grew the waves; and Andy noticed that they were now of quite respectable size; though being directly above, he could not tell much about it, only that in many spots he saw the white caps breaking, and this served as a pointer.

Would the hydroplane be able to ride such a sea in safety, in case necessity compelled them to alight upon its swelling bosom?

Frank did not seem to doubt it, for he had the utmost confidence in the ability of those aluminum pontoons to sustain a great weight without sinking. What they would possibly have to fear more than anything else, was the chance of a capsize; and of course this would spell disaster as much as anything else.

Once they overtook a sailing schooner that was speeding along with a fair breeze. Possibly those aboard thought they were making most excellent time, with everything in their favor, but the aeroplanes sped past the vessel almost as though it were a toy craft.

A faint cheer was heard from those aboard who could be seen wildly waving head-gear, or red handkerchiefs; just as though what they considered a novel air race had been engineered especially for their amusement.

When Andy took occasion to look backward again in a short time he was amazed to discover how far distant the sails of the schooner seemed. And it was this incident more than anything else that gave him to understand just what amazing speed the aeroplanes were putting in their mad race across the inland sea.

But while up to now the voyage had been without incident worthy of mention, or accident of any kind, it could hardly be expected that this immunity would continue to the very end. The splendid good fortune that had hovered over both airships was apt to be brought to a sudden termination at any moment, as Frank well knew.



CHAPTER XXII

A HYDROPLANE RESCUE

All this while Andy's nerves had been strained to a high pitch. And it was not at all singular, therefore, that when the anticipated event came to pass he gave vent to a loud cry.

"Looky! Frank; they're going to drop! Something must have happened to the motor or else a plane guy broke to cripple them!" was what he almost shrieked.

Frank was watching, though he had not uttered a single sound. He knew that the half expected crisis was now upon them. At least his heart found cause for rejoicing that if an accident had to happen, it affected the other aeroplane rather than their own. It is much easier to bear watching another's troubles than to bear your own.

What Andy had said was the truth, for the craft they were chasing after had taken a sudden dip, and was fluttering downward.

If you have ever seen a crippled bird trying hard to keep afloat, you can have a pretty good conception of how that biplane dropped lower and lower toward the water.

That it did not fall like a lump of lead spoke volumes for the magnificent management of the pilot who controlled the levers, and whose long experience had taught him just what to do in such a dreadful emergency as this.

Frank had instantly cut off much of their power, though they still continued to sweep onward toward the place of the catastrophe, and were rapidly drawing near the falling aeroplane.

Both boys stared at the terrible picture of the descending biplane nearing the heaving surface of the lake. It seemed very serious indeed, for any one to drop in this way; and yet how much more dangerous to fall upon land, where the wrecked aviators would stand a good chance of broken limbs, even though they saved their necks.

Then a cry from the impulsive Andy told that the biplane was in the water. If the engine had broken loose there was a pretty fair chance that the craft with its long extended planes would float, and even bear up the two aviators. Perhaps the quick-witted Casper Blue had looked out for just such a contingency, and found a way to free the framework from the dead weight of the motor.

Frank had all he could do to manipulate his own craft, for in order to alight successfully, even as a wild duck does, he must make a turn, and head up into the wind.

That meant the passage of a certain length of time; and meanwhile who could say what might not be happening to the imperiled men?

On the other hand, Andy could not tear his horrified gaze away from the wreck of the fallen biplane; and it was really upon him that the navigator must depend for his information as to how things were going.

Fortunately Andy could talk as well as look; no matter if his tongue did show a decided inclination to cleave to the roof of his mouth with horror, he managed to find a way to make it wag.

"It floats, Frank, sure it floats!" he ejaculated, presently, even as the other was in the act of making a sweeping curve, and skilfully ducking a squally puff of wind, turn back over the course they had just covered, to sink down upon the heaving waters when he found the chance. "Yes, they must have kicked the engine overboard. That makes three poor old Perc has lost, don't it? There they are, both of 'em, squattin' in the middle of the wreck, just as cool as you please, awaitin' for us to call in and take 'em off. Hope it don't sink before we c'n get back. If either one can't swim they'd go down like a stone. Now you're around, Frank; and we're heading straight for the place. Hurrah! Hold hard there and we'll lend you a helpin' hand!"

He even waved toward the two men by now pretty well submerged in the water, but who seemed to be still clinging to the floating aeroplane, as though recognizing that their position might be much more desperate should they cut loose from that buoy.

Frank was watching closely, to pick out a favorable opportunity to alight. Well did he know the chances he and his chum were taking in thus dropping upon the heaving surface of such a tremendous body of water as Lake Ontario. It was true that they had successfully performed this operation many times with their other hydroplane, but that was upon the much calmer waters of little Sunrise Lake, where the sea never arose heavy enough to imperil the floating aircraft. It would be much more perilous now, under these conditions; but Frank had made up his mind to attempt the rescue of those in the water, and was not to be easily daunted.

When the right opening came he allowed the hydroplane to dip gently down, making sure that there was as little violence as possible in the drop, because of the chance of burying the forward propeller under; or losing his balance, upon which so much depended.

Andy knew what he was expected to do, and was nimbly endeavoring to swing his weight this way or that after they had launched on the waves, so as to keep the pontoons on an even keel, and prevent a disastrous spill. For once this occurred, the hydroplane would be of little more advantage than the wrecked biplane, which barely upheld the two clinging men, and was evidently sinking lower under the strain, with each passing second, until the end must be in sight.

At least they had dropped safely. The pontoons had been cleverly adjusted so as to bear a just proportion of the weight, and they did their duty faithfully and well in this great crisis.

Of course, the next thing was to try and work closer to the sinking biplane, and take the men aboard, one at a time. That would be a risky proceeding, requiring all the skill that Frank could bring to the front.

In the first place he had chosen to drop beyond the wreck of Percy's biplane. This he had purposely done, in the hope that the wind might drift them down upon the other aircraft.

A minute's observation convinced Frank, however, that if they waited for this to happen, the frail support which was buoying Casper Blue and his mate up would have gone under long long before they could get within touch.

Already the second man was shrieking for them to hurry, because he could feel himself slowly but surely sinking; and he let them know that he could not swim a stroke.

Plainly, then, they must do something to quicken things, if they meant to be of any service to the two rogues, thus brought to a sudden halt just when escape had seemed most bright.

Frank remembered his engine. But would it work under such strange conditions as this? He quickly saw that the rear propeller was half buried in the water; and if it turned at all would have to churn things just as though they were in truth a queerly fashioned boat, instead of an airship, intended to mount to lofty heights, and vie with the eagle in his circling above the clouds.

Quickly, then, he started to make the trial; and Andy, seeing his movement, comprehended what he must have in mind; for he swung out in such fashion as to preserve a balance, and thus help things along as far as lay in his power.

What a sensation of relief that hum of the faithful little Kincaid engine brought in its train, as it once more took up the burden of its busy song. Why, it seemed to Andy as though he could almost shout in sudden relief, when he heard it first, and saw the water flying from the partly submerged propeller.

But Frank was wise enough not to turn on full speed, knowing what a terrific strain this condition of affairs must be upon the entire fabric, flimsy at best; and if anything gave way it was all over with them; for if a chain is only as strong as its weakest link, a heavier-than-air flying machine certainly comes under the same category.

"We're going it, Frank!" shouted Andy, when he saw that their speed had increased several hundred per cent, and that they were now heading straight for the partly submerged air navigators.

It never occurred to Andy that either of the men might offer the slightest objection to being rescued. Frank looked a little further ahead; but even he could hardly believe that Casper Blue would prefer to drown rather than be saved.

What Frank was really concerning himself about more than anything else was how he could stow away the two fellows, once they found a chance to climb aboard the hydroplane; and whether he could get enough impetus from the engine with such an unusual load, to rise from the water, once he elevated his planes.

"Hurry! oh! Hurry! I'm going down!" cried the larger man.

Casper never said a word. Possibly, being a swimmer, he did not feel the same degree of terror that his companion experienced. Then again, he may have been coolly figuring on how he might turn the rescue to his own advantage in some way; for he seemed to have that little black box slung over his back by means of the strap; and it was easy to understand that it must, as Andy had guessed, contain something of considerable more value than a mere camera.

Now they were closing in. The hydroplane round-up was being carried out in what seemed to be a successful manner; and if all went well during the next few minutes the drifting fugitives would be hauled aboard by Andy, who stood ready to act the part of gallant rescuer to the king's taste.

It happened by mere accident that they were on that side of the sinking wreck where the larger man clung; and this was just as it should have been, since he seemed more in need of help, at least in far greater distress of mind, than the smaller man.

"Get ready, Andy!" warned the pilot; "I'll shut off the power if it seems best; but it may keep us on a more even keel if we move along."

"I'm going to try and get hold, and then pull him aboard; hope we don't have a spill, though!" the other sent back, as he braced himself as best the conditions allowed.

Frank gave one little turn to the rudder, for he was afraid that they might get past without coming in reach. Then the gap was completed, and Andy, leaning over, managed to get hold of the sinking man by the collar of his coat.

There was where the greatest danger lay.

When a man or a boy has the terror of drowning pressed in upon his heart, he is usually a most unreasonable being; and will even clasp his intended rescuer about the neck, and prevent him from carrying out his plans that might have worked well only for this blundering.

"Take it easy, you!" yelled Andy, as he saw the man clutch hold of the framework of the hydroplane, and struggle desperately to work his way along to where the others were. "If you give us half a chance we'll save you, all right; but upset us and well all like as not go down together. Slower, I tell you, or I'll give you this to teach you something. This ain't an ocean liner, d'ye understand. Let up!"

Whether it was the excited words of the boy, the manner in which he flourished that short steel bar, or his ferocious looks, that brought the excited man to his senses no one could ever say; but he did relax some of his frantic movements and began to act more within reason.

This presently gave Andy the opportunity he wanted to stretch out a helping hand, and get a firm grip of the other's coat collar; after which he exerted himself to the utmost to assist him to climb aboard.

What with his own weight, and the fact that his clothes were dripping with water, the addition of the new passenger caused the delicately constructed and already heavily freighted hydroplane to sink more deeply.

Frank, in that supreme moment realized that it would be almost a hopeless task to think of once more flying, with such a cargo aboard. Possibly the best they could do would be to keep afloat, and hope that the pursuing tug might come up with them before the darkness set in; and they could all be rescued.

Now that the first of the imperiled airmen had been hauled aboard, there remained but Casper Blue himself. The wreck had not as yet sunk wholly, since, relieved from the weight of the heavy man, it seemed to possess enough buoyancy to remain on the surface of the water. But this could be only for a short time; the planes would soon be thoroughly soaked, and then the end must come, when the clinging man would find himself deprived of all support, and must swim or go down.

He had something of a half defiant look on his small sunburned face, as he saw Andy trying to draw the wreck toward him, with the evident intention of giving him the next opening. Perhaps he was half inclined to take his chances as he was, rather than allow these two boys to make him a prisoner.

Frank had his mind made up. He figured that both men had been long enough in the water to have their weapons well soaked, so that they would be in no condition to threaten their rescuers.

"The box, make him pass it up first, or we leave him here!" he called out to Andy, as the latter was about to reach out and lay hold of the smaller man.

Casper Blue glared almost savagely at Frank. For the moment the Bird boys even thought the enraged man would hurl defiance back at them, and declare that he preferred taking his chances with the wreck rather than give up the spoils.

But just then it happened, fortunately, that the remnant of the biplane began to settle more positively than before, warning him that it was folly to pin any hope on its buoying him up more than a few minutes at most.

"Here, take it!" he snarled, handing up the box; which Andy immediately passed over to his cousin before he would stretch out his hand again to render the defeated yeggman any assistance.

Then Casper Blue was drawn aboard, and lower still sank the buoyant hydroplane, until both propellers were almost wholly submerged beneath the surface of the heaving billows that came rolling on, steadily and remorselessly.



CHAPTER XXIII

BROUGHT TO BOOK—CONCLUSION

"What time is it, Frank?" asked Andy, who w as breathing very hard after his recent exertions in helping both men to get a footing on the hydroplane.

"I think pretty close to four o'clock," replied the other, though he made no attempt to take out the little nickel watch, he always carried nowadays.

The fact of the matter was that Frank did not dare trust Casper Blue. He could see that the little man was a desperate character, and that he did not view the prospect of being made a prisoner, and taken back to Bloomsbury with any great show of enthusiasm. In fact, it was a most unpleasant proposition for the bank thief to contemplate at all.

And so Frank was watching him closely. He had, before starting on this dangerous air flight that had ended so far from home, and under such singular conditions placed a little pistol in his pocket, though hardly under the belief that he would have any occasion to make use of it.

But he was now determined not to let this man get the upper hand. He could see that various desperate plans must be forming in that scheming brain of the one-time aviator, and now yeggman; and Frank was constantly on the watch so that he might not be caught napping.

"Four o'clock!" repeated Andy; "that would mean at least two more hours before the sun set, wouldn't it; and even after that it might stay light enough another hour for them to see us if they steamed along?"

"You mean the people aboard that tug, don't you?" asked Casper Blue, sneeringly.

"Yes, they seemed to be chasing after us, and I only hope they do keep moving," replied Andy, "because they must have seen the accident, that is if they had any sort of a marine glass aboard, which I reckon they did."

"And I suppose, now, you think there might be officers aboard that same tug?" the other went on to say.

"Oh! we don't know anything about that," Andy remarked, carelessly. "But if they came along after a while it'd save us from a lot of worrying. Just think, if the night set in, and the four of us weighing this poor old hydroplane down like we are what a time we'd have before another morning came around."

"It would like as not rise, if there was only two aboard, wouldn't it?" Casper asked quickly, and before Andy could understand what his question meant he had replied to it.

"Sure thing, Frank and myself have left the water many a time in a less powerful hydroplane than this, haven't we, Frank?"

"Well, turn about is only fair," said Casper, fiercely.

"Why, I don't understand what you mean by that," complained Andy.

"Two's company, four a crowd; so please skip out of this, both of you boys. My pal and me can run this shebang, and just take my word for it, we mean to do the same. Get that straight, both of you? Now, jump, I tell you, and lively, or I might be tempted to let her go; and that would be a shame after the way you rescued the two of us. Overboard with you!"

Andy gaped when he saw that the man had actually drawn out a revolver, and was aiming the same directly at him.

"Here, quit that, will you?" he demanded, feeling a flush of alarm, for even a seasoned veteran of many battles does not fancy having such a threatening weapon thrust under his nose.

"Jump, then, d'ye hear, consarn you?" shouted the man, menacingly waving his pistol; "take a header, and over you go, both of you! I'm a desperate man, and not to be fooled with. P'raps you c'n keep afloat on that wreckage long enough for the tug to come up, and pull you in. But no matter, over you go, one way or the other!"

"Just wait a bit, Casper," said a quiet voice, and turning his head the man saw that Frank had him covered very neatly, "you must know that your weapon has been soaked, and wouldn't go off, the chances are. Besides, I don't believe there's a single cartridge in the chambers. Throw it overboard, do you hear, Casper, or I may be tempted to cripple that other arm of yours!"

No doubt Frank was speaking the exact truth when he declared his belief that the revolver had not been charged since the time when Casper emptied it at the pursuing airship, in the hope of either frightening the boy aviators; or else doing some sort of damage.

He stared hard at Frank for half a minute; then with some muttered words, as if he realized the folly of butting up against fate, threw the useless weapon far out on the heaving surface of the lake.

After that a dense silence fell upon them. The men were too down-hearted to want to talk; and there was little that the boys had to communicate, because they were now in a position where they could do absolutely nothing to help themselves; and must depend entirely upon the coming of the tug.

An hour passed, and it seemed very long. All of them were more or less wet because of the splashing waves; but as the air was balmy, they cared little for such a thing as that, if only the tug would show up.

Innumerable times did Andy stretch his neck, and look toward the quarter in which it must appear, if it came at all; but the hour began to extend far into a second one, and as yet there was nothing seen that brought with it a ray of hope.

Worse still the sea was gradually getting more and more tempestuous, it seemed to Andy, though the sky remained absolutely clear, and, there was not a sign of a storm.

If that had been a fog in the far distance which Frank had sighted, the breeze must have long ago dissipated it entirely.

Lower sank the sun, until it was now not more than half an hour above the horizon, if its stay could be measured in the way of minutes and seconds. Oh! if only the friendly tug would come in sight amidst the foam-crested waves! It was really getting to be too much of a good thing, trying to keep the hydroplane from keeling over, with those waves breaking against the frail planes. If this kept up much longer, Frank was very much afraid that Percy Carberry would not be the only boy in Bloomsbury to mourn the loss of an airship.

When, therefore, Andy gave a sudden shout, and announced that he believed he had seen the smoke of the tug wreathing above the waves, all of them looked considerably relieved, even Casper himself; for on second thoughts the yeggman must have decided that it was better to be alive and in prison, than dead, and under the waters of Lake Ontario.

In five minutes they could all see the smokestack of the powerful tug, and for fear lest it should pass by and not do them any good they shouted hoarsely in unison.

"They hear us!" exclaimed Andy, whose position, somehow, allowed him to see better than any of the others, "yes, they've changed their course, and are heading this way now. It's all right, Frank; we've won out, I guess!"

But Frank was keeping an eye on the two men. He did not mean to give them even the slightest chance to play a trick in the eleventh hour. Frank Bird was a pretty hard fellow to catch napping, he usually had his eyes open, and especially when he knew there was danger around.

The tug came booming on, and they could see that there were quite a number of people aboard.

"What if some of them are from Bloomsbury?" suggested Andy. At which his cousin laughed.

"You didn't stop to think twice before you made that break, Andy," he remarked. "Tell me, by what conveyance could they have got to the lake ahead of us, when we came through by lightning express at the rate of nearly a hundred miles an hour at times? But I can see they are expecting to take charge of our friends here, because there's an officer aboard. Just keep where you are, Casper; your goose is cooked, and there's no need of making matters worse."

The man settled back again with a growl, and then burst out into a reckless laugh.

"Small difference it makes, I guess, boys, how the thing's done, so long as we've got to go to the lock-up. You might just as well have the credit for the job as anybody; and man to man, now I want to say that I'm full of admiration for the fine way you handled that hydroplane of yours. If so be you're the Bird boys I've been hearing so much about, you've got the making of crack-a-jack aviators in you. That's about all from me now."

The tug came alongside, and the two men were assisted aboard, where the police officer saw that they were promptly ironed.

"We got the word from Bloomsbury, and your father hired this tug right away, Andy Bird, to follow you out on the lake, if so be you kept after the rascals," said a tall gentleman with a white mustache, who, they afterwards learned, was the mayor of the city on the lake shore. "Now what can we do for you?"

"Please stand by, and let's see if we can get away," answered Frank, "if not we'll have to go on board, and tow the hydroplane behind, but since relieved of so much extra weight the pontoons have risen again; and I expect she'll go."

And she did, with the very first effort, beginning to move over the surface of the water in the lee of the tug; then, as Frank hastened to elevate the planes, the airship started to mount and when free from the lake a mighty cheer broke from the lips of those aboard the small vessel, even Casper Blue joining in giving the brave lads their just dues.

Frank carefully started back toward the American side of the lake. He did not know whether the capture had been made on the Canadian side or not, and as the question was never raised, even in the trail of the bank robbers it was never wholly clear in his mind.

When they reached land it was early night; and save that the wind had lulled considerably, they would not have been able to get in for a long time after that. As there was no need of their hurrying homeward, Frank and Andy consented to stay over as the guests of the mayor, who was more than pleased to have the famous Bird boys stop under his roof.

But first Frank made sure to send a message to each of their homes; as well as to Chief Waller, who would have to come on and get the two bold men who had broken into the Bloomsbury bank and about cleaned out the vault; and not content with one haul, were planning to rob the pay-car when it stopped in Bloomsbury to settle with a large number of employees centering there.

Doubtless that must have been a season of considerable excitement in the home town; and the names of Frank and Andy Bird were cheered to the echo by the crowds of town boys Larry and Elephant would lead around, burning red lights and firing off Roman candles purchased with money supplied by Dr. and Professor Bird, the happy fathers of the two young heroes.

On the following day Chief Waller was on hand with one of his men to escort the prisoners back to the town where their latest crime had been committed. Frank had already sent the little camera box with its valuable contents, just as he had received it from Casper Blue, to the president of the bank by express, not caring to hold it any longer in his hands than was absolutely necessary.

About noon, the conditions being favorable, the Bird boys sailed away amidst the cheers of half the little city, and headed directly south on a bee line for home.

Fortunately enough no further adventures overtook them on their way there, and as their coming had been announced they found the whole town in an uproar, and came near being mobbed, such was the desire of every man, woman, boy and girl to have the honor of shaking hands with them.

Percy was on hand too, with a thousand questions concerning the fate of his precious biplane, and bemoaning the fact that he seemed to be the most unlucky fellow who had ever attempted to bring honors to Bloomsbury. But there were precious few who sympathized with him; and everybody knew that all he had to do was to demand that his mother advance the ready cash to buy another flier, and it was sure to be forthcoming.

But there were other lively times in store for Frank and Andy Bird, although neither of them suspected it just then, and believed that a period of calm would likely follow their hydroplane round-up. What the nature of these exploits were the reader who has accompanied us in our voyage through the pages of this book, will learn when he purchases the next story in this series, now on sale under the title of "The Bird Boys' Aeroplane Wonder or, Young Aviators On a Cattle Ranch."

The End.