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TOM SWIFT AMONG THE FIRE FIGHTERS OR Battling with Flames from the Air

CHAPTER I

"IMPOSSIBLE, Ned! It can't be as much as that!"

"It doesn't seem possible, Ned, that we have made as much as that this past year. And this, as I understand it, doesn't include what was taken from the wreck of the Pandora?"

"You really didn't get anything to speak of out of your undersea search, Tom," replied the young financial manager, "so I didn't include it. But there's enough without that."

"Well, you've earned it, every cent, with the inventions of yourself and your father."

"Well, that's what I'm here for," remarked Ned modestly.

But Tom did not say what he had started to. He broke off suddenly, and seemed to be listening to some sound outside the room of his home where he and his financial and business manager were going over the year's statement and accounting.

But after he had finished his financial labors and had handed Tom the first of a series of statements to look over, the young financial expert began to realize that there was no moving picture house near Tom's home. Consequently the passing throngs could not be accounted for in that way.

And then had come Tom's interruption of himself when he broke off in the middle of a sentence to listen intently.

"I thought I heard Rad or Koku moving around out there," murmured Tom. "It may be that my father is not feeling well and wants to speak to me or that some one may have telephoned. I told them not to disturb me while you and I were going over the accounts. But if it is something of importance--"

"G'wan 'way from heah now!" cried the voice of a colored man.

"G'wan 'way! I'll tell Massa Tom!"

"Koku!" exclaimed Tom, with a half comical look at Ned. "He and Rad are at it again!"

The discussion and scuffle in the hall at length grew so insistent that Tom, fearing the aged colored man might accidentally be hurt by the giant Koku, opened the door. There stood the two, each endeavoring to push away the other that the victor might, it appeared, knock on the door. Of course Rad was no match for Koku, but the giant, mindful of his great strength, was not using all of it.

"No can be quiet!" declared the giant. "Too much noise in street--big crowds--much big!"

"What are the crowds doing?" asked Ned. "I thought we'd been hearing an ever increasing tumult, Tom," he said to the young inventor.

"Heah! Let me tell Massa Tom!" pleaded Rad. Poor Rad! He was getting old and could not perform the services that once he had so readily and efficiently done. Now he was eager to help Tom in such small measure as carrying him a message. So it was with a feeling of sadness that Tom heard the old man say again, pleadingly:

"Well, go ahead and tell me!" burst out Tom, with a goodnatured laugh. "Don't keep me in suspense. If there's anything going on--"

"Where is it?"

"And with this wind it'll be worse!"

"Has anything happened?" asked the young inventor.

"Heap big blaze!" added Koku.

"Fire! Fire!"

"No, it's quite a way off, on de odder side of town," answered the colored man. "But we t'ought we'd better come an' tell yo', an'--"

"Yes, suh, Massa Tom, he's done sleepin' good."

The buildings had grown up around the old Swift homestead, which, now that so much industry surrounded it, was not the most pleasant place to live in. Tom and his father only made this their stopping place in winter. In the summer they dwelt in a quiet cottage far removed from the scenes of their industry.

As they turned out of the driveway into the street they became aware of great crowds making their way toward a glow of sinister red light showing in the eastern sky.

"You said it!" ejaculated Ned. "Must be a general alarm," he added, as they caught the sound from the next street of additional apparatus hurrying to the fire.

"Where do you reckon it is?" asked Ned, as they sped onward.

Shopton, the suburb of the town where Tom lived, was named so because of the many shops that had been erected by the industry of the young inventor and his father. In fact the town was named Shopton though of late there had been an effort to change the name of the strictly residential section, which lay over the hill toward the river.

"Where is it?"

"Fireworks factory!" cried Ned. "Bad place for a fire!"

The chums had become gradually aware of the gale that was blowing, and, as they reached the summit of the hill and caught sight of the burning factory, they saw the flames being swept far out from it and toward a collection of houses on the other side of a vacant lot that separated the fireworks industrial plant from the dwellings. As Tom Swift glimpsed the fire, noted its proportions and the fierceness of the flames, and saw which way the wind was blowing them, he turned on the power to the utmost.

"I'm going down there!" cried Tom. "That place is likely to explode any minute!"

"Don't you understand?" shouted Tom in his chum's ear. "The wind is blowing the fire right toward those houses! Mary Nestor lives in one of them!"

"They may be all right," Tom went on. "I can't be sure from this distance. Or they may be in danger. It's a bad fire and--"

CHAPTER II

Only momentarily was Tom Swift halted in his progress toward the scene of the blaze in the fireworks factory. To him, and to the chum who sat beside him on the seat of the electric runabout, it appeared that the blast had actually stopped the progress of the car. But perhaps that was more their imagination than anything else, for the machine swept on down the hill, at the foot of which was the conflagration.

"I should say so! Must have been somebody hurt in that blow-up!"

"What are you going to do, Tom?" yelled his chum, as the business manager saw the young inventor heading directly for the blaze. "What's the idea?"

"I'm with you!" was Ned's quick response. "But you can't go any closer. The police are stretching the fire lines!"

He slowed his car as he approached a place where an officer was driving back the throng that sought to come closer to the blaze.

"Are there any killed?" asked Tom, stopping the car near the officer.

"I've got to go through!" replied Tom, with tightening lips. "I've got to go through, Cassidy!" He knew the officer, and the latter now seemed, for the first time, to recognize the young inventor.

His voice was lost in the roar of another explosion, not as loud or severe as the first, but more plainly felt by Tom and Ned, for they were nearer to it.

Tom started the runabout forward again.

In another moment the two young men were lost to sight in a swirl of smoke that swept across the street. And while they are thus temporarily hidden may not this opportunity be taken of telling new readers something of the hero of this story?

Tom, with the help of his father, an inventor of note, rebuilt the motor cycle adding many improvements, and it served Tom in good stead more than once.

His venture in proceeding to save Mary Nestor from possible danger in the blaze of the fireworks factory was not the first time Tom had rendered service to the Nestor family. There was that occasion on which he had sent his wireless message from Earthquake Island, as related in an earlier volume.

Tom Swift's activities in connection with his inventions had become so numerous that the Swift Construction Company, of which Ned Newton was financial manager and Mr. Damon one of the directors, had been formed. And when the rumor came that there was a chance to salvage some of the untold wealth at the bottom of the sea, Tom was interested, as were his friends.

Not to go into all the details, which are given in the last volume of this series, entitled "Tom Swift and His Undersea Search," suffice it to say that the venture was begun. Matters were complicated owing to the fact that Mary Nestor's uncle, Barton Keith, was in trouble over the loss of valuable papers proving his title to some oil lands. Mary mentioned that a person, Dixwell Hardley, was the man who, it was supposed, was trying to defraud her relative. And the complications may be imagined when it is said that this same Hardley was the man who had interested Tom in the undersea search for the riches of the Pandora.

"Whew, Tom, some heat there!" gasped Ned, lowering his arm from his face, an action which had been necessitated by Tom's daring in driving the car close to the blazing fireworks factory.

"Lucky she didn't take the notion to blow up as we were passing," grimly commented Ned. "Where are you aiming for now?"

A few seconds later they had passed through the black pall that was slashed here and there with red slivers of flame, and, coming to a more open space, Ned and Tom cleared their eyes of smoke.

But the conflagration was still a fierce one. Not half the big factory was yet consumed, and every now and then there would sound dull, booming reports, causing nervous screams from the women who were out in front of their homes, while the men would crouch down as though fearing a shower of fiery embers.

"I think the worst is over, as far as you people here are concerned," the young inventor replied. "The wind has shifted a bit."

"That ought to do the trick," said Tom, with a show of confidence. "Anybody hurt around here?" he asked. "One of the policeman said he heard several were killed."

"Too bad!" murmured the young inventor. "You're not worried about your home, are you, Mrs. Nestor?" he asked of Mary's mother.

"Neither it would, if we've got to burn, but I don't believe we have--now," said her husband. "That last explosion and the shift of the wind saved us. I appreciate your coming over, Tom," he went on. "We might have needed your help. It's queer there isn't some better, or more effective, way of fighting a fire than just pouring on a comparatively insignificant bit of water," he added, as, from what was now a safe distance, they watched the firemen using many lines of hose.

"Yes, for little baby blazes that have just started," went on Mr. Nestor. "But in all the progress of science there has not been much advance in fighting fires. We still do as they did a hundred years ago--squirt water on it, and mighty little of it compared to the blaze. It would take a week to put this fire out by the water they are using if it were not for the fact that the blaze eats itself up and has nothing more to feed on."

The young inventor was about to reply when several firemen, equipped with smoke helmets which they adjusted as they ran, came running down the street.

"Some men are trapped in a small shed back of the factory," was the answer. "We just heard of it, and we're going in after them. Oh! Oh--my--my heart!" he gasped, and he sank to the sidewalk. Evidently he was either overcome by the smoke and poisonous gases or by his exertions.

"I'll fill your place! See if you can grab a hat, Ned, and come on!"

One of the firemen pointed through the luridly-lighted smoke to a small structure near the main building. This was beginning to burn. With quick blows of an axe the door was hewed down, and the rescue party, including Tom and Ned, made its way inside. In the light from the blaze, as it filtered through the windows, it could be seen that a man lay in a huddled heap on the floor.

The man was taken to the Nestor yard and stretched out on the grass. Word was relayed to one of the ambulance doctors who were on the scene attending to several injured firemen, and in a short time the man, who, it appeared, had been overcome by smoke, was revived.

"Yes, it was touch and go," remarked the young doctor, who had used heroic measures to bring the man back from the brink of the grave. "But you'll live now, all right."

"Of what use to live?" he murmured. "You might as well have let me die in there. Life isn't worth living now," and he sank into a stupor, while Tom and the others looked wonderingly at one another.

CHAPTER III

"I don't believe so," answered the doctor. "At least I don't believe that he is dying, though his mind may be wandering. He isn't injured--at least not outwardly. Just temporarily overcome by smoke is what it looks like to me. But of course I haven't made a thorough examination."

"The best medicine he can have is fresh air, the doctor replied. "He's better off out here than in the house. Though if he doesn't revive presently I will send him to the hospital."

"I don't want to go to the hospital," he murmured. "I'll be all right presently, and can go home, though--Oh, well, what's the use?" he asked wearily, as though he had given up some fight. "I've lost everything."

"You said it!" commented the other grimly.

"Who is he?" asked Tom, as the physician knelt down beside the silent form.

"I've seen him going into the main offices several times," remarked Mary, who was standing beside Tom. "He seemed to be one of the company officers."

"Mentally, as well as physically," put in Ned. "He acted as if sorry that we had saved his life."

"I know him."

"Name's Baxter, Josephus Baxter. He's a chemist, and he works in the fireworks factory here. Not as one of the hands, but in the experiment laboratory. I've seen him there late at night lots of times. That's how I got acquainted with him. He was going in around two o'clock one morning, and I stopped him, thinking he was a thief. He proved his identity, and I've passed the time of day with him many a time since"

"Down on Clay Street," and the officer mentioned the number. "He lives all alone, so he told me. He's some sort of an inventor, I guess. At least I judged so by his talk. Do you want an ambulance, Doctor?" he asked the physician.

"I'll take him in the runabout," eagerly offered Tom. "But if he lives all alone will it be safe to leave him in his house?"

"Then I'll take him home with me!" announced Tom. "We have plenty of room, and Mrs. Baggert will feel right at home with some one to nurse. Bring the runabout here, will you please, Ned?"

"It's all over!"

"Myself, yes, maybe," said the man bitterly, and he managed to rise to his feet. "But what of my future? It is all gone! The work of years is lost."

"Oh, it isn't the fire--that is directly," said the man, in the same bitter tones. "I've lost everything! The scoundrels stole them! And I--Oh, never mind!" he cried. "What's the use of talking? I'm down and out! I might just as well have died in the fire!"

"Though if I do lapse into unconsciousness you might as well let me keep on sleeping until the end," said Mr. Baxter bitterly to Tom and Ned, as they drove away from the scene of the fire with him.

The man did not answer, and the two chums did not feel much like talking, for they were worn out and weary from their exertions at the fire. The factory had been pretty well consumed, though by strenuous labors the blaze had not extended to adjoining structures. The home of Mary Nestor was saved, and for this Tom Swift was thankful.

"Can I do anything for you?" asked Tom, as he was about to go out and close the door.

"Do you mean Amos Field and Jason Melling of the fireworks firm?" asked Tom, for the names were familiar to him in a business way.

"You don't mean that!" cried Tom. "Deliberately to start a fire in a factory where there was powder and other explosives! That would be a terrible crime!"

"Were your formulae for the manufacture of fireworks?" asked Tom.

"Perhaps it will not be as bad as you think," said Tom, recognizing the fact that Mr. Baxter was in a nervous and excited state. "Matters may look brighter in the morning."

"I'll see you again in the morning," Tom said, trying to infuse some cheerfulness into his voice.

"How is he?" asked the young business manager.

"You generally do have--lots of 'em!" Ned rejoined.

"Yes, the pressure here isn't what it ought to be," Ned agreed. "And some of our engines are old-timers."

"Of course," Ned answered. "There are plenty of chemical fire extinguishers on the market, too, Tom. If your idea is to invent a new hand grenade, stay off it! A lot of money has been lost that way."

Tom paused in a listening attitude. There was the rush of feet and a voice cried:

CHAPTER IV

"That can't be Koku and Rad in one of their periodic squabbles, can it?" asked Ned.

"Guess I'd better go along," remarked Ned. "Sounds as if you'd need help."

"I'll get 'em! I'll get the scoundrels who stole my secret formulae that I worked over so many years! Come back now! Don't put the match near the powder!"

"Have you my formulae?" he asked. "I want them back!"

Josephus Baxter glared about with wild eyes, but between them Tom and Mrs. Baggert managed to get him to drink the mixture.

"I'll do my best," declared Tom cheerfully. "Now please lie down."

"Ah done guess Ah ain't wanted much mo'," muttered Rad sadly.

"Will yo', really, Massa Tom?" exclaimed faithful Rad, his face lighting up. "Dat's good! Is yo' goin' off after mo' diamonds, or up to de caves of ice?"

"Anyt'ing yo' wants, Massa Tom! Anyt'ing yo' wants!" offered the now delighted Rad, and he went to bed much happier.

"Oh, I don't know that it's much of a game," was the answer. "But I just have an idea that a big fire in a towering building can be fought from above with chemicals, as well as from the ground with streams of water.

"I wasn't thinking of a hose," returned Tom. "What then?" asked the young financial manager.

Ned was silent a moment, considering Tom's daring plan and project. Then, as it became clearer, the young banker cried:

"That's my notion," Tom said.

"Thanks," commented Tom dryly. "But there are several things to be worked out before we can start. I've got to devise some scheme for carrying a sufficient quantity of chemicals, and invent some way of releasing them from an airship over the blaze. But that last part ought to be easy, for I think I can alter my warfare bomb-dropping attachment to serve the purpose.

"You haven't delved much into chemistry, have you?"

"No," agreed Ned. "You have enough types of airships to be able to select just the best one for the purpose. But, say, Tom!" he suddenly cried, "why not ask him to help you?"

"Mr. Baxter. He's a chemist. And though he says his formulae are about dyes and fireworks, maybe he can put you in the way of inventing a chemical solution that will be death to fires."

"It's worth trying," declared Ned. "What do you suppose he means, Tom, saying that Field and Melling stole his formulae?"

"We inventors are a suspicious lot, Ned, as you probably have found out," he added with a smile. "We imagine the rest of the world is out to cheat us, and I presume Josephus Baxter is no exception. Still, there may be some truth in his story. I'll give him all the help I can. But I'm going into the aerial firefighting game. I've been waiting for something new, and this may be it."

"That's right. Tomorrow is another day. I hope Mr. Baxter gets some rest. Sleep will improve him a lot, the doctor said."

"Who?" Tom wanted to know.

"No, he's been off on a little trip, blessing everything from his baggage check to his suspender buttons," laughed the young inventor, as he recalled his eccentric acquaintance. "I shall be glad to see him again."

The hopes that Mr. Baxter would be greatly improved in the morning were doomed to disappointment. He was in no actual danger, the doctor said, but his recovery from the effects of the smoke he had breathed was not as rapid as desired or hoped for.

"I wouldn't dream of it!" Tom exclaimed. "Let him stay here by all means. We have plenty of room, and Mrs. Baggert has been wishing for some one to nurse. Now she has him."

But as everything possible had been done, Tom decided to go ahead with the new idea that had come to him--that of inventing an aerial chemical fire-fighting machine.

"All right, Tom, I'm with you any time you need me," Ned promised.

And one day, when Ned called, Tom electrified his chum with the exclamation:

"What?"

"Where are you going to get the fire?" asked Ned. "You can't have a sky-scraper blaze made to order, you know."

"Sure thing!" cried Ned. "And I hope the experiment is a success!"

Ned and he were busy putting the can of Tom's new chemical extinguisher in the airship when the door of the hangar was suddenly opened and a very much excited man entered crying:

CHAPTER V

Tom and Ned were so startled by the entrance of the excited man with his cry of "Fire!" that the young inventor nearly dropped the tank of liquid extinguisher he was helping to hoist into the aeroplane. Then, as he caught sight of his visitor, Tom exclaimed:

"Experiment, Tom Swift! Experiment! Bless my Latin grammar! but you'd much better be calling out the fire department to play on that blaze down in your meadow. What is it--your barns or one of your new shops?"

"And the fire department is here," added Tom.

"Here," and Tom pointed to his airship--one of the smaller craft--into which the tank of chemicals had been hoisted.

"Yes. Fighting fires from the air. I got the idea after the fireworks factory went up in smoke. Will you come along? There's plenty of room."

"Oh, yes," replied Tom. "I had Rad and Koku light a big pile of packing boxes, to represent, as nearly as possible, on a small scale, a burning building. I plan now to sail over it and drop the tins of chemicals. They are arranged to burst as they fall into the blaze, and I hope the carbon dioxide set loose will blanket out the fire."

The airship was wheeled out of the hangar and was soon ready for the flight. A big cloud of black vapor down in the meadow told Tom and Ned that Koku and Eradicate had done their work well. The giant and the colored man had poured oil over the wood to make a fierce blaze that would give Tom's new chemical combination a severe test.

"Contact!" cried Tom sharply, and the man stepped forward to give the big blades a final turn that would start the motor. There was a muffled roar and then a steady staccato blending of explosions. Tom raced the motor while his men held the machine in place, and then, satisfied that all was well, the young inventor gave the word, and the craft raced over the ground, to soar aloft a little later.

Tom had told Ned and Mr. Damon, before the trio had entered the machine, what he wanted them to do. This was to toss the chemicals overboard at the proper time. Of course in his perfected apparatus Tom hoped to have a device by which he could drop the fire extinguishing elements by a mere pressure of his finger or foot, as bombs were released from aircraft during the war. But this would serve for the time being.

At last the signal came. Mr. Damon and Ned heaved over the side the metal containers of the powerful chemicals.

Tom and his friends leaned over the side of the machine to watch the effect. They could see the chemicals strike the blaze, and it was evident from the manner in which the fire died down that the containers had broken, as Tom intended they should to scatter their contents.

Truly the effect of the chemicals was seemingly to cause the fire to go out, but it was only a momentary dying down. Koku and Rad had made a fierce, yet comparatively small, conflagration, and though for a time the gas generated by Tom's mixture dampened the blaze, in a few seconds--less than half a minute--the flames were shooting higher than ever.

"Something wrong!" declared the young inventor, when they were back at the hangar, climbing out of the machine.

"Didn't use the right kind of chemicals," Tom answered. "From the way the flames shot up, you'd think I had poured oil on the blaze instead of carbon dioxide."

"Don't blame you," Tom assented. "But I'll do the trick yet! This is only a starter!"

"If I could only get my secret formulae back!" he sighed, as he thanked Tom for his kindness. "I'm sure Field and Melling have them. And I believe they got them the night of the fireworks blaze; the scoundrels!"

One afternoon, at the end of a week in which he had been busily and steadily engaged on this work, Tom finally moved away from his laboratory table with a sigh of relief, and, turning to Eradicate, who had been helping him, exclaimed:

"Good lan' ob massy, I hopes so!" exclaimed the colored man. "It sho' do smell bad enough, Massa Tom, to make any fire go an' run an' drown hisse'f! Whew-up! It's turrible stuff!"

Leaving Rad to mix some of the chemicals, a task the colored man had often done before, Tom went out into the yard near his laboratory to start a blaze on which his new mixture could be tested.

"Oh, Massa Tom, I'se blowed up! It done sploded right in mah face!"

CHAPTER VI

"I hope nothing serious has happened," was the thought that flashed through Tom's mind. "But I'm afraid it has. I should have mixed those new chemicals myself."

"Ho! Ho!" laughed Koku. "You much better hab me work, Master Tom. I no make blunderstakes like dat black fellow! I never no make him!"

"Yep, dat Rad he don't as know any more as to blow up de whole place!" chuckled Koku.

But what gave Tom more concern than anything else was the sight of Eradicate lying in the midst of broken glass on the floor. The colored man was moaning and held his hands over his face, and the young inventor could see that the hands, which had labored so hard and faithfully in his service, were cut and bleeding.

"It sploded! It done sploded right in mah face!" moaned Eradicate. "I--I can't see no mo', Massa Tom! I can't see to help yo' nevah no mo'!"

Though the fumes from the chemicals that had exploded were choking, causing both Tom and Koku to gasp for breath, they never hesitated. In they rushed and picked up the limp figure of the helpless colored man.

Probably Koku meant "greased pig," but Tom never thought of that. All his concern was for his faithful Eradicate.

It was a fine and generous spirit that the giant was showing, though Tom had no time to speculate on it just then.

"Whatever Master Tom say," returned the giant humbly, as he looked with pity at the suffering form of his rival--a rival no longer. It seemed that Rad's working days were over.

"Where are you worst hurt, Rad?" asked Tom, with a view to getting a line on which physician would be the best one to summon.

"Oh, I guess it isn't as bad as that," said Tom. But when he had a glimpse of the seared and wounded face of his faithful servant he could not repress a shudder.

"Bless my bottle of arnica, Tom!" exclaimed the eccentric man, with sympathy in his voice. "What's this I hear? One of your men tells me old Eradicate is killed!"

"It wasn't your fault, Tom. Perhaps he did something wrong," said Mr. Damon.

"He's doing as well as can be expected for the present," was the answer. "I have given him a quieting mixture. His worst injury seems to be to his face. His hands are cut by broken glass, but the hurts are only superficial. I think we shall have to get an eye specialist to look at him in a day or two."

"Well, we'll not decide right away," replied the doctor, as cheerfully as he could. "I should rather have the opinion of an oculist before making that statement. It may be only temporary."

"Me take care ob him," put in Koku, who had been humbly standing around waiting to hear the news. "Me never be mad at dat black man no more! Him my best friend! I lub him like I did my brudder!"

Everything possible was done for Eradicate, and the doctor said that it would be several days, until after the burns from the exploding chemicals had partly healed, before the eye-doctor could make an examination.

"And hope for the best!" advised Mr. Damon.

"I can't understand it," said Tom. "I was trying to make a fire extinguishing liquid, and it turned out to be a fire creator. I don't see what was wrong."

"Yes," agreed Tom. "I'll check them over and try to find out where the mistake happened."

"I don't mind that in the least, if Rad doesn't lose his eyesight," was the answer of the young inventor, and his friends could see that he was much worried, as well he might be.

"It will take a month to get this back in shape," he said ruefully. "I guess I shall have to postpone my experiments."

"What can he do?" Tom wanted to know. "He hasn't any laboratory."

"Yes," Tom nodded.

"Glad you did," returned Tom. "But do you suppose his plant is large enough to enable me to work there until mine is in shape again?"

"I'll do it!" decided Tom, more hopefully than he had spoken since the accident.

CHAPTER VII

"I'm glad to see you, Mr. Swift," said the chemist, who seemed to have aged several years in the few weeks that had intervened since the fire. "I want to thank you for giving me a chance to start over again."

"As much as possible without my secret formulae," was the answer. "If I only had those back from the rascals, Field and Melling, I would be able to go ahead faster. As it is, I am working in the dark. For some of the formulae were given to me by a Frenchman, and I had only one copy. I kept that in the safe of the fireworks concern, and after the fire it could not be found."

"No. But the doors were open, and much of what had been inside was in ashes and cinders. Amos Field claimed that the explosion had blown open the safe and burned a lot of their valuable fireworks formulae too."

"I'm sure of it!" was the fierce answer. "Those men are unprincipled rogues! They had been at me ever since I was foolish enough to tell them about my formulae to get me to sell them a share. But I refused, for I knew the secret mixtures would make my fortune when I could establish a new dye industry. Field and Melling claimed they wanted the formulae for their fireworks, but that was only an excuse. The formulae were not nearly so valuable for pyrotechnics as for dyes. The fireworks business is not so good, either, since so many cities have voted for a 'Sane Fourth of July.'"

"Sounds like a good idea," said the chemist, rather dreamily.

"I haven't given that much study myself," said Mr. Baxter. "But you are welcome to anything I have, Mr. Swift. The whole place, such as it is, will be at your disposal at any time. I intend to have it in better shape soon, but I have to proceed slowly, as I lost nearly everything I owned in that fire. If I could only get those formulae back!" he sighed.

"He is dead," answered the chemist. "Everything seems to be against me!"

"Yes," agreed Mr. Baxter, "you have big assets when you have your health and eyesight."

"Well?" asked Tom nervously, as he faced the physician.

Tom could not repress a gasp of pity.

"Poor Rad!" murmured Tom. "This will break his heart."

"We'll see to that," declared Tom. "Is he otherwise injured?"

Tom and his friends were forced to take such comfort as they could from this verdict, but no hint of their downcast feelings were made manifest to Eradicate.

"Oh, he talked a lot of big Latin words, Rad--bigger words than you used to use on your mule Boomerang," and Tom forced a laugh. "All he meant was that you'd have to stay in bed a while and let Koku wait on you."

"I here right upsidedown by you, Rad," said Koku, and his big hand clasped the smaller one of the black man.

"Huh! me an' you good friends now," said the giant. "Anybody what hurt my Rad, I--I--bust 'im! Dat I do!" cried the big fellow.

But Eradicate caught the sound of his young employer's footsteps and called:

"Yes, Rad. Is there anything you want?"

"Indeed I do!" laughed Tom, and Eradicate also chuckled at the recollection.

For Tom the following days, that lengthened into weeks, were anxious ones. There was a constant worry over Eradicate. Then, too, he was having trouble with his latest invention--his aerial fire-fighting apparatus. It was not that Tom was financially dependent on this invention. He was wealthy enough for his needs from other patented inventions he and his father owned.

But there was something about this chemical fire extinguishing mixture that defied the young inventor's best efforts. Mixture after mixture was tried and discarded. Tom wanted something better than the usual carbonate and sulphuric combination, and he was not going to rest until he found it.

"Well, I'm not going to give up," was the firm answer.

"Well, it doesn't seem to work," said the young inventor ruefully. "Everything I do lately goes wrong."

"I wish you would!" exclaimed Tom eagerly. "My head is woozie from thinking! Suppose I leave you to yourself for a time, Mr. Baxter? I'll go for an airship ride."

"Will you come along, Ned--Mr. Damon?" asked Tom, as he prepared to leave the improvised laboratory, the repairs on his own not yet having been finished.

"And I promised my wife I'd take her riding, Tom," said the jolly, eccentric man. "Bless my umbrella! she'd never forgive me if I went off with you. But I'll run you to your first stopping place, Ned, and you to your hangar, Tom."

"Guess I'll drop down and get Mary Nestor," he decided, after riding about alone for a while and finding that the motor was running sweetly and smoothly. "She hasn't been out lately."

"Go for a ride? I just guess. I will!" cried Mary, with sparkling eyes. "Just wait until I get on my togs."

"Oh, isn't it glorious!" said Mary, as she sat at Tom's side. They were in a little enclosed cabin of the craft--which carried just two--and, thus enclosed, they could speak by raising their voices somewhat, for the noise of the motor was much muffled, due to one of Tom's inventions.

"I do love these rides, Tom!" the girl cried one day when the two were soaring aloft. "And this one I really believe is better than any of the rest. Though I always think that," she added, with a slight laugh.

"What's the matter, Tom?" she asked. "Has anything happened? Is Rad's case hopeless?"

"But what makes you so serious?"

"I should say so! You haven't told me one funny thing that Mr. Damon has said lately."

Tom suddenly stopped speaking and began rapidly turning several valve wheels and levers.

"The motor has stopped," Tom answered, and the girl became aware of a cessation of the subdued hum.

"Not necessarily so," Tom replied. "It means we have to make a forced landing, that's all. Sit tight! We're going down rather faster than usual, Mary, but we'll come out of it all right!"'

CHAPTER VIII

A jar, a nerve-racking tilt to one side, the creaking of wood and the rattle of metal, a careening, and then the machine came to a stop, not exactly on a level keel, but at least right side up, in the midst of a wide field.

"Scared?" he asked, smiling.

"I hope not," answered the young inventor. "At least if it is, the damage is on the under part. Nothing visible up here. But let me help you out. Looks as if we'd have to run for it."

"No. But it's going to rain soon--and hard, too, if I'm any judge," Tom said. "I don't believe I'll take a chance trying to get the machine going again. We'll make for that farmhouse and stay there until after the storm. Looks as if we could get shelter there, and perhaps a bit to eat. I'm beginning to feel hungry."

Tom did not answer. He was making a hasty but accurate observation of the state of his aeroplane. The landing wheels had stood the shock well, and nothing appeared to be broken.

"What caused it?" asked Mary, glancing up at the clouds, which were getting blacker and blacker, and from which, now and then, vivid flashes of lightning came while low mutterings of thunder rolled nearer and nearer. "Something seemed to be wrong with the carburetor," Tom answered. "I won't try to monkey with it now. Let's hike for that farmhouse. We'll be lucky if we don't get drenched. Are you sure you're all right, Mary?"

She proved this by hastening along at Tom's side. And there was need of haste, for soon after they left the stranded aeroplane the big drops began to pelt down, and they reached the house just as the deluge came.

"No, I don't remember being here before," Tom answered. "But I've passed the place often enough with Ned and Mr. Damon. I guess they won't refuse to let us sit on the porch, and they may be induced to give us a glass of milk and some sandwiches--that is, sell them to us."

"Guess they didn't hear that," observed Tom, as the echoes of the blast died away. "I mean my knock. The thunder drowned it. I'll try again."

"Guests must go to the front door."

"That can be arranged--yes," said the old woman, who spoke with a foreign accent. "But you must go to the front door. This is the servant's entrance."

"Is this a restaurant--an inn?" he asked.

"All right," Tom agreed good-naturedly. "I'm glad we struck the place, anyhow."

"I see what has happened," Tom remarked, as he opened the oldfashioned ground glass door and ushered Mary in. "Some one has taken the old farmhouse and made it into a roadhouse--a wayside inn. I shouldn't think such a place would pay out here; but I'm mighty glad we struck it."

The old farmhouse, one of the best of its day, had been transformed into a roadhouse of the better class. On either side of the entrance hall were dining rooms, in which were set small tables, spread with snowy cloths.

"Somebody is fond of seclusion," thought Tom, as he and Mary took their places. And as he glanced over the bill of fare his ears caught the murmur of the voices of two men coming from behind the screen. One voice was low and rumbling, the other high-pitched and querulous.

"I wasn't very hungry until I came in," she answered, with a smile. "But it is so cozy and quaint here, and so clean and neat, that it really gives one an appetite. Isn't it a delightful place, Tom? Did you know it was here?"

"I should think you would have had enough experience by this time," laughed Mary, for it was not the first occasion that she and Tom had dined out.

"I must bring Ned and Mr. Damon here," said Tom. "They'll appreciate the quaintness of this inn," for many of the quaint appointments of the old farmhouse had been retained, making it a charming resort for a meal.

"And cause the waiter to look at me as though I had brought in an escaped inmate from some sanitarium," laughed Tom. "No use talking, Mr. Damon is delightfully queer! Now what do you want for dessert?"

Tom gazed idly but approvingly about as she scanned the list. The sound of the rumbling and the higher-pitched voices had gone on throughout the entire meal, and now, as comparative silence filled the room, the clatter of knives and forks having ceased, Tom heard more clearly what was being said behind the screen.

"Yes," agreed he of the rumbly voice, whom Tom thought of as Mr. Low, "it was a close shave. If it hadn't been for his chemicals, though, there would have been a cleaner sweep."

Tom seemed to stiffen at this, and his hearing became more acute.

"What's this? What's this?" thought Tom, shooting a glance at Mary and noting that apparently she had not heard what was said. "What strange talk is this?"

CHAPTER IX

A crash had resounded through the room, but it spoke well for the state of Tom's nerves that he gave no indication that he had heard the noise. It was caused by a waiter when he dropped a plate, which was smashed into pieces on the floor. The noise was startling enough to excuse Mary for jumping in her chair, and it seemed to put an end to the strange talk of "Mr. High" and "Mr. Low" back of the screen, for after the crash of china only indistinct murmurs came from there. But Tom Swift did not cease to wonder at the import of the talk about chemicals, fire, and the mention of the name of Josephus Baxter.

"Two if you like," answered the young inventor. "They say tea is good for the nerves, and you seem to need something, judging by the way you jumped when that plate fell."

"That's right!" he conceded. "I forgot about that. My fault, entirely!"

"I wonder who they are, and what they meant by that talk," mused Tom, as the waiter served the Murolloas to him and Mary. "Poor Baxter! It looks as if he might have more enemies than the fireworks men he accuses of having taken his valuable formulae. I must see him soon, and have a talk with him. Yes, I must make a special point to see Josephus Baxter. But first I'd like to have a glimpse of these men.

Tom's judgment as to the statures of the men, based on the quality of their voices, was not exactly borne out. For it was the big man who had the high pitched, squeaky voice, and the little man who had the deep, rumbling tones.

Tom took the chance to make certain this conjecture when Mary left her seat, announcing that she was going to the ladies' parlor to arrange her hair, which the run to escape from the rain had disarranged.

"Yes, sir, it came suddenly. Hope you didn't have to change a tire in it, sir."

"Oh, then--" Obviously the man was puzzled.

"We accommodate a few cars in what was once the barn, and we have a good mechanic, sir. If you'd like to see him--"

"Yes, sir. And they had engine trouble, I believe. Our man fixed up their machine."

"Oh, them two fellers!" exclaimed the mechanician, after he had agreed to go with Tom to where the airship Scud was stalled. "They come from over Shopton way. They own a fireworks factory-or they did, before it burned."

"That's the names they gave me," said the man. "Little man's Field. He gave me his card. I'm going to get a job overhauling his car. There isn't enough work here to keep a man busy, and I told 'em I could do a little on the outside. This place just started, and not many folks know about it yet."

And this, when the young inventor and the mechanician from Meadow Inn reached the stranded Scud, was found to be the case. The storm had passed, and Mary told Tom she would not mind waiting at the Inn until he found whether or not he could get his air craft in working order.

"Glad you found it," said Tom heartily. "Now I guess we can ride back."

"If their talk meant anything at all," reasoned the young inventor, "it meant that there was some deal in which Josephus Baxter got the worst of it. 'Putting it over on him in the fire,' could only mean that. Of course it isn't any of my business, in a way, but I don't think it is right to stand by and see a fellow inventor defrauded.

"But I have my own troubles, I guess, trying to perfect that fire-fighting chemical, and I haven't much time to bother with Field and Melling, unless they come my way."

"Yes?" replied Tom, questioningly.

"A dye company?" repeated the young inventor, all his suspicions coming back as he recalled that Baxter had said his formulae were more valuable for dyes than for fireworks.

"Yes, the Germans used to have a monopoly of the dye industry," said Tom, hoping the man would talk on. He need not have worried. He was of the talkative type.

"Where's that?" asked Tom.

"No," Tom answered, "I haven't. Been too busy, I guess. So Field and Melling have their offices there?"

"It is a nice place," agreed Tom. "Well, now let's see if she'll work," and he nodded at the Scud.

"Are you sure we shall not have to make an. other forced landing?" she asked with a smile, a she took her place in the cockpit.

"I suppose I'll have to take a chance," said Mary.

"What is their game?" Tom found himself asking himself over and over again. "What did they 'put over' on poor Baxter?"

"Is Rad worse? Is there more trouble with his eyes?" asked the young inventor.

"Mad?" queried Tom.

"Oh, you mean Mr. Baxter, who was in the fireworks blaze," translated Tom. "Where is he, and what's the matter?"

CHAPTER X

"Oh, Tom, I'm glad you have arrived," said his father. "You remember Mr. Baxter, of course."

"I hope he hasn't been getting on dad's nerves," thought Tom, as he took a seat. The elder Mr. Swift had been quite ill, and it was thought for a time that he would have to give up helping Tom. But there had been a turn for the better, and the aged inventor had again taken his place in the laboratory, though he was frail.

"No, you are right, unfortunately," said Mr. Baxter gloomily. "The trouble is that everything I do is a failure. Up to a little while ago I thought I might succeed, in spite of Field and Melling's theft of the formulae from me. I made a purple dye the other day, and tested it today. It was a miserable failure, and it got on my nerves. I came to see if you could help me."

"Well, I need better laboratory facilities," the man went on. "I know you have been very kind to me, Mr. Swift, and it seems like an imposition to ask for more. But I need a different lot of chemicals, and they cost money. I also need some different apparatus. You have it in your big laboratory. That wouldn't cost you anything. But of course to go out and buy what I need--"

"Oh, thank you!" exclaimed the inventor. "Now I believe I shall succeed in spite of those rascals. Just think, Mr. Swift! They have started a big new dye factory."

"And I'm almost sure they're using the secret formulae they stole from me!" exclaimed Mr. Baxter. "But I'll get the best of them yet! I'll invent a better dye than they ever can, even if they use the secrets the old Frenchman gave me. All I need is a better place to work and all the chemicals at my disposal."

"And if I can do anything let me know," put in Mr. Swift. "I shall be glad to get in the harness again, Tom!" he added.

"Perhaps I may be able to give you a hint or two after I get settled down," suggested Mr. Baxter.

"I'll never forget this," said Mr. Baxter, and there were tears in his eyes as he shook hands with Tom, who tried to make light of his generous act.

The little conference broke up, and Tom was on his way to his own special private laboratory when there came the sound of some excitement in the corridor outside and Mr. Damon burst in.

"I'm sure I don't know," answered the young inventor, with a smile. "What about?"

"If you can believe the evidence of your own eyes, I'm far from being in that state," laughed Tom. "And as for Mary, she just left here with Ned Newton."

"No gladder than I," said Tom. "We had to make a forced landing, that was all," and he made as light of the incident as possible when he saw the look of terror in his father's eyes.

"It was a false alarm," replied Tom. "And now, Mr. Damon, if you want to smell some perfumes come with me."

"I mean I'm going to experiment some more with fireextinguishing chemicals," laughed the young inventor. "If you want to--"

"Guess I'm used to 'em," was the answer. And then, leaving his father to entertain Mr. Damon and to make arrangements for Mr. Baxter's use of the main laboratory, he betook himself to his own private quarters.

"Well, Tom, how goes it?" asked Ned one day when he came over to call on his chum. "Are you ready to accept contracts for putting out skyscraper blazes in all big cities?"

"You mean another experiment?"

"When are you going to try it?" asked Ned.

"Then I'd better get my leather suit on," remarked Ned, starting to take off his street coat. Tom kept for his chum a full outfit of flying garments, one suit being electrically heated.

"Why, I thought you were going to test your aerial fire fighting dingus!" exclaimed Ned.

"Then you want me, and perhaps Mr. Damon to take the stuff up in the machine? Excuse me. I don't believe I care to run an airship myself."

Ned Newton followed his chum out into the big yard near one of the shops. Erected in it, and evidently a new structure, was a large wooden scaffold in square tower shape with a long overhanging arm and a platform on the extremity. Beneath it was a pit dug in the earth, and in this pit, which was directly under the outstanding arm of the tower, was a pile of wood and shavings, oil-soaked.

"Yes," Tom answered. "There will be time enough to go on with the airship end of it after I get the right combination of chemicals. And by having a metal container with the stuff in dropped from this frame work, I can station myself as near the burning pit as I can get and watch what happens."

"Mr. Baxter suggested it," replied Tom. "That helpful idea more than pays me for what I have done for him. So now, if you're ready, I'd like to have you watch with me and make some notes, one of us on one side of the pit, and one on the other. There are always two sides to a fire, the leeward and the windward, and I want to see how my chemicals act in both positions."

"No, he is a bit too heavy for the framework, which I had put up in a hurry. I'd have Rad do it, but he's out of the game."

"I don't know," sighed the young inventor. "All I can do is to hope. He is very patient, and Koku is devoted to him. All their little bickerings and squabbles seem to have been forgotten."

"Light her up!" cried Tom Swift, and a match was thrown in among the oiled wood. In an instant a fierce blaze shot up, as hot, in proportion, as would come from any burning building.

"All ready up there?" he called to his helper perched high in the air.

Would success or failure attend the young inventor's project?

CHAPTER XI

He quickly reviewed, mentally, the composition of the chemical compound. He had made it as strong as possible, and he had spared no pains to insure a hot fire, so that the test would not be too simple.

"Nothing. I was just making sure I hadn't forgotten anything," Tom answered. "I guess I haven't."

"Let her go!"

There was a scattering of the fire in the pit as the extinguisher bomb fell among the blazing embers. Then followed a slight explosion when the bomb broke, as it was intended it should.

Almost immediately he had his answer. For after a fierce burst of the tongues of fire following the fall of the bomb, there was a distinct dying down of the conflagration in the pit. Great clouds of smoke arose, but the fire was quenched in a great measure, and as the fire-blanketing gas continued to be generated from the chemicals liberated from the bomb, there was a further dying down of the crackling fire.

Tom did not answer. He leaned forward and looked eagerly down into the pit. He was about to join with Ned in agreeing that he had, indeed, solved the problem, when, to his surprise, the flames started up again.

"Not that I know of," was the puzzled answer. "I don't exactly understand this myself, Ned. By all calculations this fire ought to have died a natural death, but now it is breaking out again. I think what must have happened is that a quantity of the oil they poured on collected in a pool and didn't get all the effects of the chemicals from the bomb. Then the oil started to blaze."

"Oh, I've got another bomb up there," and Tom pointed to his helper who was still perched on the overhanging arm. "I was prepared for some such emergency as this. Drop the other one!" Tom yelled, and again a dark object fell. bursting in the pit and again liberating the gas that was supposed to choke any fire.

"Hurray, Tom! That does the business!" But the young inventor shook his head. "I'm not quite satisfied," he remarked. "It didn't work quickly enough. What I want is a chemical combination that will choke the fire off first shot."

"Yes. But 'good enough' isn't what I want," Tom said. "I've got to work on that chemical compound again. I think I know where I can improve it."

"But not enough," declared Tom. "I want the fire to be out more quickly than this one was. I think I can improve that chemical compound, and I'm going to do it."

"What is your next move?" asked Ned, as Tom started for his small, private laboratory.

"Bless my vest buttons! then I'm not coming in, exclaimed a voice which could proceed from none other than Mr. Damon. And he it proved to be. He had driven over from Waterford in his automobile and had arrived just as the fire test was concluded.

"Poor Rad! How is he?" asked Mr. Damon, walking along with Tom and Ned.

"And when they do will he be able to see?" asked Mr. Damon.

"I will," promised the eccentric man. "At any rate I'll not venture near your perfume shop, Tom Swift!"

"All right," assented Tom. "I've got several new schemes to try. Some of them ought to work."

"And that's about all the benefit I derived from being with those scoundrels, Field and Melling," said Mr. Baxter gloomily.

"I'm positive of it, but I can't prove anything. They threatened to get the best of me when I would not sell them, for a ridiculously low sum, an interest in the secrets. And I believe they did get the best of me during that fire."

"How is that? What do you know? Can you help me prove anything against them?" eagerly asked the chemist.

Thereupon he related the conversation he had overheard while with Mary at the wayside inn. The eyes of Josephus Baxter gleamed as he listened to this recital.

"What did happen?" asked Tom. "All I know is that you were overcome in the laboratory room."

"One night they came to see me as I was working there over my formulae. They pretended to have discovered something in an expired patent that nullified what I had. I did not believe this to be so, and I brought out my formulae to compare with theirs-or what they said they had. The next thing I remember was that the fire broke out and my formulae disappeared. Then I was overcome, and I did not care what happened to me, for, having lost the valuable dye formulae, I did not think life worth living.

"I know," said Tom sympathetically. "I've been in the same boat myself. But are you sure they took the papers which meant so much to you?"

"No," agreed Tom, "it was mostly smoke in there, and smoke won't melt tin. Nor did I see any box on the table when we carried you out."

"Not much, for a fact," agreed Tom. "Well, with what I heard and what you tell me, perhaps we can work up a case against them later. I'll go over it with Ned. He has a better head for business than I."

Tom and Mr. Baxter spent many days and nights perfecting the fire-extinguisher chemical, and, after repeated tests, Tom felt that he was nearer his goal.

"Anything special on?" asked the young manager.

"All right, I'm with you," assented Ned. "Newmarket," he added musingly. "Isn't that where Field and Melling are now?"

"I shall need a little more time," remarked Ned. "But I think we can at least bluff them into playing into our hands. I have a report to hear from a private detective I have hired."

A little later Tom and Ned were speeding through the air on their way to Newmarket. The rapid flier was making good time at not a great height when Ned, leaning forward, appeared to be gazing at something in the near distance.

"No. But what's that smoke down there?" and Ned pointed. "It looks like a fire!"

He did not finish what he started to say, but changed the direction of his air craft and headed directly toward a pall of smoke about a mile away.

"Look, Tom!" cried Ned. "It's an immense tree on fire!"

"Yes, as sure as Mr. Damon would bless something if he were here! It's a tree on fire up near the top!"

Ned wondered at this remark on the part of his chum as the airship drew nearer the blazing monarch in the patch of woods over which they were then hovering.

CHAPTER XII

"I fancy it can easily be explained," answered the young inventor. "We'll go into that later. Here, Ned, grab hold of that tin can on the floor and take out the screw plug."

"I want you to drop it as nearly as you can right into the midst of the tree that's on fire."

Ned picked up from the floor of their aeroplane a metal can similar to those Tom used to hold oil or perhaps spare gasoline when he was experimenting on airship speed. The opening was closed with a screw plug, with wings to afford an easier grip. As Ned unscrewed this his nostrils were greeted by an odor that made him gasp.

Ned leaned over the side of the craft and had a good view of the strange sight. The tree that was on fire was a dead oak of great size, dwarfing the other trees in the grove in which it stood. In common with other oaks this one still retained many of its dried leaves, though it was devoid, or almost devoid, of life. Ned noticed in the branches many irregularly shaped objects, and it appeared to be these that were on fire, blazing fiercely.

"Let her go, Ned!" cried Tom. "You'll be too late in another second!"

And then, before the eyes of Tom and Ned, the fire seemed to die out as a picture melts away on a moving picture screen. The smoke rolled away in a ball-like cloud, and the flames ceased to crackle and roar.

It was!

"My new aerial extinguisher," answered Tom, with justifiable pride in his voice. "This fire happened in the nick of time for me, Ned. I had a tin of my new combination in the car, not with any intention of using it, though. I intended to pour it in the new containers I am having made in Newmarket to see if it would corrode them, a thing I wish to avoid.

"Well, I should say so!" agreed his chum. "That blaze was doused for fair. The test could not have been better. But what in the name of a volunteer fire department set that tree to blazing, Tom?"

Ned was capable of managing an airship, especially under Tom's watchful eye, and as this craft was one with dual controls there was no difficulty in shifting from one steersman to the other.

"And now," observed Ned, as his chum resumed the wheel, "suppose you enlighten me on how that tree came to be on fire--if you didn't set it yourself."

So the aeroplane made a landing, and then the mystery was explained. The dead oak, to which some of its last year's foliage still clung, was the abiding place of thousands of crows that had built their nests in it. There were hundreds of the big nests, made of dried sticks, mostly, and these made an ideal fuel for the fire.

"I fancy the birds flew away as soon as they saw their homes on fire," said Tom. "Or they may not have been at home. Flocks of crows often go to some distant feeding ground for the day, returning at night. I fancy that is what happened here.

And Tom's theory was, eventually, proved to be true. Some lads, wandering afield, had set fire to the crows' nests and then, frightened as they saw a bigger blaze than they intended, ran away.

Tom had lingered long enough to make sure that his latest combination of chemicals had been just what was needed. He felt sure that by using a larger quantity, no fire, however fierce, could continue to blaze.

It did not take long for Tom to secure another supply of the new chemical. He then went with it to the firm in Newmarket that was making his containers, or "bombs" as he called them.

"I believe you have at last hit on the right combination," said the chemist. "You are on the road to success, Tom. I wish I could say the same of myself."

Busy days followed for the young inventor. Now that he was convinced he had at last evolved the right mixture of chemicals, he prepared to make a test on a larger scale than merely a blazing tree.

Preparations were made, and the day before Tom was to carry out his plans he received a letter.

"Nothing much. Only Mary is going away, and I had expected her to be at the test," Tom answered.

"Oh, no, only for a couple of weeks. She is going to visit an uncle and aunt in Newmarket, or just outside of that city. Another uncle, Barton Keith, has offices in the Landmark Building, I believe."

"Yes. But don't mention Mary's uncle in connection with them," laughed Tom. "He wouldn't like it."

Ned well remembered Mary's uncle, who had been associated with Tom in recovering the treasure in the undersea search.

This Tom did, though Ned noticed that his chum acted as though lonesome on his return.

CHAPTER XIII

"It took you long enough," Ned remarked as Tom entered the main office of the plant, having been to see Mary off on her trip to Newmarket. This was following his call of the night before to learn more particulars of her unexpected visit.

"And did you?"

"Getting poetical in your old age!" laughed Ned. "Well, here is that statement you said you wanted me to get ready. Want to go over it now?"

"Of what--your new aerial fire fighting apparatus?"

"Let me know when you do," begged Ned. "I want to see you do it."

Then he began several days and nights of hard work. And he was glad to have the chance to occupy himself, for, though Tom professed not to be much affected by the departure of Mary Nestor, he really was very lonesome.

"About as usual," was the answer. "He sends word by Mary that he'll be glad to see us any time we want to call. He has some nice offices in the Landmark Building."

"Well, yes--that and other things," agreed Tom. "Say, we had some exciting times on that undersea search, didn't we?"

"No, I didn't get a chance. Besides, I wanted to keep away from the Landmark Building."

"Oh, I might run into Field and Melling, and I don't want to see them until I can accuse them, and prove it, of having taken Mr. Baxter's dye formulae."

"Yes," assented Tom. "It's a big building--the tallest ever erected in that city, and a fine structure. Though while they were about it I don't see why they didn't make it fireproof."

"Yes, it was a mistake not to have the Land mark Building fireproof," admitted Tom. "And Mr. Keith says the owners are beginning to realize that now. It is what is called the 'slow burning' construction."

These were busy days for the young inventor. He laid aside all his other activities in order to perfect the plans for manufacturing his new chemical fire extinguisher on a large scale. For Tom realized that while a small quantity of chemicals in a compound might act in a certain way on one occasion, if the bulk should happen to be increased the experimenter could not always count on invariably the same results.

So Tom wanted to mix up a big tank of his new chemical compound and see if it would work in large quantities as well as it did with the small amount Ned had dropped on the blazing tree.

"There's the stuff!" exclaimed Tom, not a little proudly, as he waved his hand toward an immense carboy in the main shop. "That's what I hope will do the trick. Just take a--"

"I wasn't going to open it," laughed the young inventor. "It has a worse odor and seems to choke you more in a big quantity than when there's only a little. I was just going to shake the carboy to let you realize how full it was."

"There are to be two tests," answered Tom. "The first, and the smaller, will be in the pit, as before, only this time we shall have what, I believe, will be the successful combination of chemicals to drop on it.

"Will there be any smell?" asked the eccentric man, who seemed to have a dislike for anything that was not as agreeable as perfume.

"On those conditions I'll go along," agreed Mr. Damon. "But bless my wedding certificate, Tom! don't tell my wife. She thinks I'm crazy enough now, associating with you and flying occasionally. If she thought I would help you battle with flames from the air she'd likely never speak to me again."

Preparations for the test went on rapidly. In the morning a fire was to be started in the same pit where the experiment had partly failed before.

To this end he had purchased from a farmer the right to set on fire an old ramshackle barn, standing in the midst of a field about three miles outside of Shopton. The barn was on an untilled farm, the house having been destroyed some years before, and it was not near any other structures, so that, even in a high wind, no damage would result.

The time came for the preliminary trial, and there were a few anxious moments after the oil-soaked boards and boxes in the pit were set ablaze.

"You've struck it, Tom! You've struck it!" cried Ned.

Quite a throng was on hand when the old barn was set ablaze. Tom and Ned and Mr. Damon were there with the airship which had been especially fitted to carry the bombs filled with the extinguisher.

Necessarily they had to circle off away from the blaze to get to the necessary height, but Tom soon brought the airship around again and headed for the black pall of smoke which marked the place of the blazing barn.

Higher mounted the flames, and more fiercely raged the fire. The heat of it penetrated even aloft, where Tom and his friends were scudding along in the airship.

CHAPTER XIV

Almost as though some giant hand had dropped an immense cloak over the fire in the barn, so did the blaze die down instantly after Tom Swift's extinguishing liquid had been dropped into the seething caldron of flame. For a moment there was even no smoke, but as the embers remained hot and glowing for a time, though the flames themselves were quenched, a rolling vapor cloud began to ascend shortly after the first cessation of the fire. But this only lasted a little while.

"Bless my insurance policy, I should say so!" exclaimed Mr. Damon. "It was certainly neat work, Tom!"

"Look so! Why, hang it all, man, it is so!" declared Ned. "That fire went out as if sent for by a special delivery telegram to give a hurry-up performance in another locality. Look, there's hardly any smoke even!"

"Yes, I guess she doesn't need a second dose," observed Tom, when he saw how effective had been his treatment of the fire. "I had an additional batch of chemicals on hand, in case they were needed," he added, and he tapped some unused bombs at his feet.

"Hardly that yet," said Tom, with a laugh. "Now that I have my chemical combination perfected, or practically so, I've got to rig up an airship that will be especially adapted for fighting fires in sky-scrapers."

"I want a little better bomb-releasing device, for one thing. This worked all right. But I want one that is more nearly automatic. Then I am going to put on a searchlight, so I can see where I am heading at night."

"No. But one patterned after that." Tom answered.

"No," answered the young inventor, as he made his usual skillful landing. "You know all the big city fire departments have searchlights now for night work and where there is thick smoke. It may be that some day, in fighting a sky-scraper blaze from the clouds at night, I'll have need of more illumination than comes from the flames themselves."

"Mighty clever piece of work, Tom Swift!" declared a deputy chief. "Of course we won't have much use for any such apparatus here in Shopton, as we haven't any big buildings. But in New York, Chicago, Pittsburgh and other cities--why, it will be just what they need, to my way of thinking."

"Thank you. But you don't need to go to that trouble," asserted Tom. "My idea isn't to have every sky-scraper equipped with an airship extinguisher."

"Well, I think there ought to be one, or perhaps two, in a big city like New York," Tom answered. "Perhaps one outfit would be enough, for it isn't likely that there would be two big fires in the tall building section at the same time, and an airship could easily cover the distance between two widely separated blazes. But if I can perfect this machine so it will be available for fires out of the reach of apparatus on the ground, I'll be satisfied."

And that was the verdict of all who had witnessed the performance.

Tom Swift owned several airships, and he finally selected one of not too great size, but very powerful, that would hold three and, if necessary, four persons. This was rebuilt to enable a considerable quantity of the fire-extinguishing liquid to be stored in the under part of the somewhat limited cockpit.

The giant was aching to be with Tom and help in the new work, but Koku was faithful to the blinded Eradicate, and remained almost constantly with the old colored man.

While the colored man was, in fact, unable to see, following the accident when Tom was experimenting with the fire extinguisher, it was hoped that sight might be restored to one eye after an operation. This operation had to be postponed until the eyes and wounds in the face were sufficiently healed.

Rad was delighted to hear of Tom's success with the new apparatus, after having been told how quickly the barn fire was put out.

"All right, Rad, there'll be plenty for you to do when the time comes," said the inventor. And he could not help a feeling of sadness as he left the colored man's room.

But, hoping for the best, Tom plunged into the work ahead of him. He did not want to offer his aerial fire extinguisher to any large city until he had perfected it, and he was now laboring to that end.

"Any special object in view?" asked Ned, as Tom headed across country. "Are you going to put out any more tree fires?"

"What I want to try now is the stability of this with all I have on board," he resumed. "If she is able to travel along, and behave as well as she did before I made the changes, I'll know she is going to be all right. I don't expect to put out any fires this trip."

Tom and Ned had a glimpse of the lake, dotted with many motor boats and other craft, as the airship ascended until it was above the clouds. Then, for a time, nothing could be seen by the occupants but masses of feathery vapor.

Down out of the heights they swept at a rapid pace. A few moments later they had burst through the film of clouds and once more the lake was below them in clear view.

"Look, Tom! Look! A motor boat in some kind of trouble! She's sinking!"

CHAPTER XV

But that an accident had happened, and that trouble, if not, indeed, danger, was imminent, was at once apparent to the young inventor and the other occupant of the swiftly moving airship.

"Help! Help!" came the impassioned appeals, floating up to Tom and Ned.

"What are you going to do, Tom?" asked Ned, "You can't land on the water!"

Ned saw, now, what Tom's object was. On one shore of the lake was a large, level field, suitable for a landing place for the craft of the air. At least it looked to be a suitable place, but Tom would be obliged to take a chance on that. This field sloped down to the beach of the lake, and as Ned and his chum came nearer to earth they could see several boats on shore, though no persons were near them. Had there been, probably they would have gone to the rescue.

"Hold fast, Ned!" cried Tom, as they neared the earth. "We may bump!"

"Good work, Tom!" cried Ned, as the Lucifer slackened her speed, the young inventor having sent her around in a half circle so that she now faced the lake. Then Tom and Ned climbed from the cockpit, throwing off goggles and helmets as they ran to the shore where there were several rowboats moored.

There was a little dock at this point on the lake, and the boats appeared to be held at it for hire. But no one was in charge, and Tom and Ned made free with what they found. They considered they had this right in the emergency.

"Get one of the rowboats and fasten it to the back of the launch!" Tom directed Ned. "I don't believe this craft will hold them all," and he nodded toward those aboard the sinking boat -for it was only too plainly sinking now.

"She's humming now," announced Tom, as he turned on the naphtha, and threw in a blazing match to ignite it, this act saving his hand. Naphtha engines are a trifle treacherous.

Tom speeded the naphtha craft to its limit, and, fortunately for those in danger, it was a fast boat. In less time than they had thought possible, the young inventor and his chum were near the boat that was now low in the water--so low, in fact, that her rail was all but awash.

"Take it easy now," advised Tom, approaching with care. "We've got room for you all. Ned, get back in the rowboat and bring that alongside--on the other side. We'll take you all in," he added.

"Sure, girls first!" agreed the skipper of the disabled craft. "Hit a submerged log," he explained to Tom, as the work of rescue proceeded. "Stove a hole in the bow, but we stuffed coats and things in, and made it a slow leak. Kept the engine going as long as we could, but I thought no one would ever come! Lucky you happened to see us from up there!"

Tom and Ned had anticipated this, however, and had their craft well out of the way of the suction.

"Oh, what ever would we have done without you?" half sobbed one girl.

Then more rescue boats came up, but those in the naphtha craft, and Ned's smaller one, refused to be transferred, and remained with our friends until safely landed at the dock.

"Pretty slick act, Tom," remarked Ned.

"What's the matter?"

He did not finish his threat, but the look on his face was enough to show his righteous anger.

"I've got evidence enough--in my own mind!" declared Mr. Baxter.

"Oh, I don't want you bothered over my troubles," said the chemist. "You have enough of your own. But I'm at my wit's end what to do next."

"It's partly that, yes," said the other, in a low voice. "If I had those dye formulae, I'd be a rich man."

In return for his kindness to a fellow laborer, Tom received from Mr. Baxter some valuable hints about fire-extinguishing chemicals, one hint, alone, serving to bring about a curious situation.

"Have you anything special to do, Tom?" asked the eccentric man. "If you haven't I wish you'd take a ride with me. Not for mere pleasure! Bless my excursion ticket, don't think that, Tom!" cried his friend quickly.

"Yes," Tom answered. "As it happens I am going to Newmarket myself."

"It isn't altogether Mary. Though I am going to see her," Tom admitted. "It has to do with a little apparatus I am getting up. I can capture several birds in the same auto, so I'll go along."

"Fire! Fire!" cried Mr. Damon, rather needlessly it would seem, as any one could see the blaze.

CHAPTER XVI

Tom Swift's companion in the automobile was sufficiently acquainted with this old expression to understand readily what it meant. And as he directed his car as close as was safe to the blazing car, Mr. Damon asked:

"I'm going to try," was the grim answer.

"Wait Tom, I'll slow up a little more," said Mr. Damon, as he applied the brakes with more force. "Bless my court plaster! don't jump and injure yourself."

Tom held in readiness a small hand extinguisher. It was one he had constructed from an old one found in the shop, but it contained some of his own chemicals, the original solution having been used at some time or other. It was the intention of the young inventor to put on the market a house-size extinguisher after he had disposed of his big airship invention.

Tom did not answer, but ran in as close as was necessary and began to play a small stream from his hand extinguisher on the blazing car. He was thus able to direct the white, frothy chemical better than when he had shot it from the airship, and in a few seconds only some wisps of curling smoke remained to tell of the presence of the fire. The automobile was badly charred, but the damage was not past redemption.

"Yes. But this wasn't much," Tom said. "I didn't use half the charge. Short circuit?" he asked Field and Melling who were now returning, having seen that the danger was passed.

"No thanks necessary," said Tom, a bit shortly, as he turned to go back with Mr. Damon to their car. "It's what any one would do under like circumstances."

Tom was wondering if they knew who he was and of his association with Josephus Baxter. He did not believe the men recognized him as the person who had been at the Meadow Inn one day with Mary. They had hardly glanced at him then, he thought.

"It is the Swift Aerial Fire Extinguisher," said Tom gravely, with a glance at Mr. Damon.

"I am Tom Swift," put in the young inventor quickly. "And this is one of my inventions. I might add," he said slowly, looking first Melling and then Field full in the face, "that I was aided in perfecting the chemical extinguisher by Josephus Baxter."

"Baxter!" cried Field.

"Not officially," Tom answered, delighted at the chance to "rub it in," as he expressed it later. "I have been helping him, and he has been helping me since he lost his dye formulae in--in your fire!"

"He believes he did," asserted Tom. "I helped carry him out of the laboratory of your place when he was almost dead from suffocation. He remembers that he had the formulae then, but since has been unable to find them."

"We could have the law on him for that!" squeaked the bigger Melling.

"Well, he--we, I--that is, we haven't anything from Baxter that we didn't pay for," declared Field. "And if he goes about saying such things he'd better be careful. I am going--"

"We're much obliged to you, Mr. Swift, for putting out the fire in our car. But for you it would have been destroyed. And if you ever want to sell the extinguisher process of yours, you'll find us in the market. We are going into the dye business on a large scale, and we can always use new chemical combinations."

"Oh, thank you, we'll look over our machine before we leave it," said Melling. "It may be that we can get it to go."

So Field and Melling were left standing in the road near their stranded car, which, but for Tom Swift's prompt action, would have been only a heap of ruins.

"Oh, but it's good to see you again, Tom!" cried Mary, after the first greeting. "What have you been doing, and what's all that white stuff on your coat?"

"What's the matter with your aunt, Mary? She seems worried about something," he said, after the aunt with whom Mary was staying had come in, greeted Tom briefly, and gone out again.

"It isn't that it will make him so very poor," Mary went on. "But Uncle Barton Keith--you remember you went on the undersea search with him--Uncle Barton warned Uncle Jasper not to go into the Landmark Building scheme."

"Yes. And now he's sorry, for not only may he lose money, but Uncle Barton will laugh at him, and Uncle Jasper hates that worse than losing a lot. But tell me about yourself, Tom. What have you been doing? And is Eradicate going to get better?"

But he was interrupted by loud voices in the hall. He recognized the tones of Mary's Uncle Jasper saying:

CHAPTER XVII

Mary's uncle, Jasper Blake, always an impetuous man, opened the door so quickly that Tom, who was standing near it talking to Mary, barely had time to move aside.

"There isn't any guessing about it, Uncle Jasper," said Mary, with a laugh and a look at Tom to warn him not to tell her relative that he had just befriended Field and Melling. "For," as Mary said to Tom later, "he would positively rave at you."

"I hope you never get roped in as I have been," said Mr. Blake, as he sat down. "Those scoundrels, Field and Melling, would rob a baby of his first tooth if they had the chance!"

"That's the story they tell," said Uncle Jasper. "I was foolish enough to invest in the Landmark Building, and now I'm likely to lose it all in a lawsuit."

"And that isn't the worst," went on Mr. Blake. "But Barton-that's your friend of the submarine--will give me the laugh, for he was asked to invest in the same building, and didn't."

"Nothing those two scoundrels have anything to do with will turn out right," declared Mary's uncle. "And to think of their nerve when they ask me to go in with them on a dye scheme!"

"Well, take my advice and don't become interested to the extent of investing any money," warned Mr. Blake. "I'm not going to."

"You don't say so!" cried Mr. Blake. "Tom Swift, there's something wrong here! Let you and me talk this over. I begin to see how I may be able to take a peep through the hole in the grindstone," a colloquial expression which was as well understood by Tom as were some of Mr. Damon's blessing remarks.

"Don't go," urged Tom, but she said to him that she would see him before he left, and then she went out, leaving her uncle and the young inventor busily engaged in talking.

Impetuous as he often was, Mr. Blake was for calling in the police at once, and having the two men arrested. But Tom counseled delay.

"But they may skip out!" objected Mary's uncle.

"Their hands! Huh! They'll take precious good care that the trouble and responsibility of it are on other people's hands before they go," declared Mr. Blake. "However, I suppose you're right. Barton Keith sets a deal by your opinion since that undersea search, and while I don't always agree with him, I do in this case. Especially since he is likely to have the laugh on me."

"Mary was saying something about your faithful old retainer being in trouble," said Mr. Blake. "I'm sorry to hear about it."

Tom found Mary waiting for him after he had left her uncle, and, after a short talk with her, he made ready to ride back with Mr. Damon, who, after having attended to several other matters, was now outside in his car.

"In a week or two," she answered. "I'll send word when I'm ready and you can come and get me."

"Bless my phonograph, Tom Swift! but what is the matter? Has Mary broken the engagement?"

Other matters had to do with what Mary's uncle had told Tom about the interest manifested by Field and Melling in some dye industry.

"It's too early to say for a certainty," replied the medical man, "but I am not as hopeful as I was, Tom, I'm sorry to say."

"No, he is doing as well as he can be expected to right here. Besides, he has his friends around him, and the companionship of that giant of yours, absurd as it may seem, is really a tonic to Eradicate. I never saw such devotion on the part of any one."

"Oh, I wouldn't say that," declared the medical man. "I haven't given up, though there are some symptoms I do not like. However, I am going to wait a week and then make another test."

Field and Melling, he heard incidentally, had their machine towed to a garage for repairs, but beyond that no word came from the two men. Josephus Baxter remained at work over his dye formulae in one of Tom's laboratories, but the young inventor did not see much of the discouraged old man.

It was within a few days of the time when Tom was to call in a committee of fire insurance experts to give them a demonstration of the efficiency of his aerial fire-fighting machine. He was putting the finishing touches to his craft and its extinguishingdropping devices when he received a call from Mr. Baxter.

"Not very well," was the answer. "I've tried, in every way I know, to get on the track of the missing methods perfected by that Frenchman, but I can't. I'd be a millionaire now, if I had that dye information."

"I certainly do. And the reason I believe so is that I was over at a chemical supply factory the other day when an order came in for a quantity of a very rare chemical."

"This chemical is an ingredient called for by one of the dye formulae that were stolen from me. I never heard of its being used for anything else. I at once became suspicious. I learned that this chemical had been ordered sent to Field and Melling in their new offices in the Landmark Building."

Mr. Baxter shook his head.

"That's the trouble," agreed Tom. "But I'll give you all the help I can. And, come to think of it, I believe you might interest Mr. Blake. He has no love for Field and Melling, and he has several keen lawyers on his staff. I believe it would be a good thing for you to talk to Mr. Blake."

"He may," agreed Tom. "I'll fix it so you can meet him. But what do you think of this combination, Mr. Baxter? It is my very latest solution for putting out fires. I'm loading an airship up with some of the bomb containers now, and--"

"Fire! Fire! Fire!"

"And not far away," said Tom, as he caught the reflection of a red gleam in the sky.

"Tom! Tom Swift! There's quite a fire in town! Don't you want to try your new apparatus on it?"

Without waiting for a reply from the chemist, Tom caught him by the hand and led him toward the side door that gave egress to the yard where one of the airships was housed. Tom caught sight of Ned, who was hastening toward him.

"I'm going to try to put it out!" Tom answered. "Want to come?"

CHAPTER XVIII

Tom Swift and Ned Newton were so accustomed to acting quickly and in emergencies that it did not take them long to run out the airship, which Tom had in readiness, not especially for this emergency, but to demonstrate his new apparatus to a committee of fire underwriters whom he had invited to call in a few days.

"You're going to have all the chance you want, Tom, by the looks of that blaze," commented Ned Newton.

Outside in the streets near the Swift house and shops could be heard the rattle of fire apparatus, the patter of running feet, and many shouts from excited men and boys.

"Some one said it was the new Normal School. But that's farther to the north," was Ned's answer. "By the way the blaze has increased since I first saw it, I'd take it to be the lumberyard."

"No, we'll have to go to New York or Newmarket for one of those," observed Ned. "All ready, Tom?"

"What's the matter, Tom?" asked the voice of Mr. Swift, as he came out into the yard, having been attracted by the flashing lights and the noise of the aircraft motor, as Tom gave it a preliminary test.

"Guess there isn't any question about that," said his business manager.

"Take care of yourself, my boy!" he advised, as there came a moment of silence before the throttle of the aircraft was opened to send it on its upward journey. "Don't take too many risks."

Then came the roar of the motor as Tom cut out the muffler to gain speed and, a moment later, he and his two friends were sailing aloft with a load of fire-extinguishing chemicals.

"These she is!" cried Ned, for when the exhaust from the motor was sent through the new muffler Tom had attached it was possible to talk aboard the Lucifer. The young manager pointed down toward the earth, over which the craft was then skimming, though at no great height.

"It sure is," assented Tom. "I know I haven't enough stuff to cover as big a blaze as that, but I'll do my best. Fortunately there is no wind to speak of," he added, as he guided the craft in the direction of the fire.

"Well, the wind has to be allowed for in dropping anything from an aeroplane," Tom answered. "And, naturally, it does spoil your aim to an extent. But the reason I'm glad there is no wind to speak of is that the chemical blanket I hope to spread over the fire won't be so quickly blown away."

"The regular land apparatus is on hand," observed Ned, for they were now so near the fire that they could look down and, in the reflection from the blaze, could see engines, hose-wagons and hook and ladder trucks arriving and deploying to different places of advantage, from which to fight the lumberyard fire that was now a roaring furnace of flames.

"Yes," was the answer.

Attention of those who had gathered to look at the fire was about evenly divided between the efforts of the regular department and the pending action by Tom Swift. The latter was not long in turning loose his latest sensation.

"Good work!" cried Ned.

Tom wheeled the airship in a sharp, banking turn, and headed for the heart of the fire in the lumberyard. It was clearly getting beyond the control of the regular department.

"All ready," was the answer.

Again the three in the airship leaned eagerly over the side of the cockpit to watch the effect. It was almost magical in its action.

"This will do the trick!" cried Ned. "I'm certain it will."

"But the fire is certainly dying down," declared Mr. Baxter.

And from the watching crowds, as well as from the hard-working members of the Shopton fire department, came cheers of delight and encouragement as they saw the work of Tom Swift's aerial fire-fighting machine.

As Tom had said, the absence of wind was in his favor, for the generated gases remained just where they were wanted, directly over the fire like an extinguishing blanket, and were not blown aside as would otherwise have been the case.

"Well, I. guess that's all," said Tom, when the final bomb had been dropped. "That was the last of them, wasn't it, Ned?"

"Good!" cried Tom. "But, all the same, I wish I had been able to make the first mixture work."

And the following day, after Tom had received the thanks of the town officials and of the fire department for his work in subduing the lumberyard blaze, the young inventor called Josephus Baxter in consultation.

"I will, and without pay," said the chemist.

CHAPTER XIX

"There, Tom Swift, it ought to work now!"

"Do you think you've hit on the right combination?" asked the young inventor, whose latest idea, the plan of fighting fires in skyscrapers from an airship as a vantage point, was taking up all his spare moments.

"That certainly is too bad," declared Tom. "I wish I could help you as much as you have helped me."

"You've done a lot for me," declared Tom. "If it had not been for your help this chemical compound would not be nearly as satisfactory as it is, nor as cheap to manufacture, which is a big item."

"And that's what I want," declared Tom. "I think I shall go ahead now, and proceed with the manufacture of the stuff on a large scale."

"I'm going to sell the patent and the idea that goes with it to as many large cities as I can," Tom answered. "I'll even manufacture the airships that are needed to carry the stuff over the tops of blazing skyscrapers, dropping it down. I'll supply complete aerial fire-fighting plants."

It was the conclusion of the final tests of an improved chemical mixture, and the reaction that had taken place in the test tube was the end of the experiment. Success was now again on the side of Tom Swift.

Try as he had, he could not succeed in getting the right chemical combination to perfect the dye process imparted to him by his late French friend. With the disappearance of the secret formulae went the good luck of Josephus Baxter.

"I know who have those formulae," declared the chemist again and again. "It is those scoundrels, Field and Melling. And they are planning to build up their own dye business with what is mine by right!"

As the young inventor had said, he was now ready to put his own latest invention on the market. After many tests, aided in some by Mr. Baxter, a form of liquid fire extinguisher had been made that was superior to any known, and much cheaper to manufacture. Veteran members of fire departments in and about Shopton told Tom so. All that remained was to demonstrate that it would be as effective on a large scale as it was on a small one, and big cities, it was agreed, must, of necessity, add it to their equipment.

"And I wish you all sorts of luck," said Mr. Baxter. "Now I am going to have another go at my troubles. I have just thought of a possible new way of combining two of the chemicals I need to use. It may be I shall have success."

"Is Rad--has anything happened--shall I get the doctor?"

"Oh!" exclaimed Tom, and he understood now. Messenger boys frequently came to Tom's house or to the shops, and they took delight in poking fun at Koku on account of his size, which made him slow in getting about. The boys delighted to have him chase them, and something like this had evidently just taken place, accounting for Koku's agitation.

"For me!" exclaimed the chemist. "Who could be writing to me? It's a big firm of dye manufacturers," he went on, as he caught a glimpse of the superscription in the upper left hand corner.

"I'm on the trail! On the trail of those scoundrels at last!" exclaimed Josephus Baxter. "This gives me just the evidence I needed! Now I'll have them where I want them!"

CHAPTER XX

"I'm on their trail! Now I'm on their trail!"

"It's about Field and Melling! That's who it's about!" exclaimed Mr. Baxter, with a smothered exclamation. "Look, Tom Swift, this letter is addressed to me from one of the biggest dye firms in the world--a firm that is always looking for something new!"

"But I will have something new when I get those secret formulae away from those scoundrels!" declared Mr. Baxter.

"Ah, that's the point! Now I think I can prove it," declared Mr. Baxter. "Look, Tom Swift! This letter is addressed to me in care of Field and Melling at the office I used to have in their fireworks factory."

"Exactly. The place where you saved me from a terrible death. Well, if you will notice, this letter was written only two days ago. And it is the first mail I have received as having been forwarded from that address since the fire. I know other mail must have come for me, though."

"Those scoundrels confiscated it!" declared the chemist. "But, in some manner, perhaps through the error of a new clerk, this letter was remailed to me here, and now I have it. It is of the utmost importance!"

"Why, it is directed to me, outside and in, and it makes an inquiry about the very dyes of the lost secret formulae, one dye in particular."

"Well, it's this way," went on Mr. Baxter. "I had, in the office of Field and Melling, all the papers telling exactly how to make the dyes. After the fire, in which I was rendered unconscious, those papers disappeared.

"Which means what?" asked Tom.

"And it proves, Tom Swift, that Field and Melling are in possession of my dye formulae, and that they have tried to dispose of some of the dye to this firm. Not knowing anything of this, the firm replies to me. So now I have direct evidence--just what I wanted--and I can get on the trail of the scoundrels who have cheated me of my rights."

"It does look as though you might get at them through this," Tom said, as he handed back the letter. "But I'm afraid you'll have to get further evidence before you could convict them in a court of law--you'll have to show that they actually have possession of your formulae."

"I'll help you all I can," offered Tom. And events were soon to transpire by which the young inventor was to render help to the chemist in a most sensational manner.

"Yes, you have done enough for me," said Mr. Baxter. "But I think now, with this letter as evidence, we'll be able to make a start."

"I will go and see Mr. Damon," decided Mr. Baxter. "He always gives good advice."

"Thanks, I'll be glad to go with you," said the chemist.

"Bless my law books, Mr. Baxter! but I do believe you're on the right trail at last. Come in, and we'll talk this over."

For several days Tom was so busy that he had little time to devote to Mr. Baxter, or even to see him. He learned, however, that the chemist and Mr. Damon were in frequent consultation, and the young inventor hoped something would come of it.

He closed with one of these, some distance off, and agreed to fly over in his aircraft and extinguish a fire which was to be started in an old building which had been condemned. and was to be destroyed. This was in a city some four hundred miles away and when Ned Newton called on him one afternoon he found Tom busily engaged in loading his sky-craft with a heavy cargo of the newest liquid extinguisher.

"What do you mean?"

"No use sending a boy on a man's errand," said Tom. "I'm counting on you to go with me, Ned--you and Mr. Baxter. We leave this afternoon for Denton."

The giant did, indeed, seem to be laboring under the stress of some emotion.

"Has anything happened?" asked Tom, quickly. "No, not yet. But dat pill man--he say by tomorrow he know if Rad ever will see sunshine more!"

"Yes. What so pill man say," repeated Koku.

CHAPTER XXI

"WELL, what do you say, Tom?" asked Ned, in a low voice.

"It's a pretty heavy load," agreed the young manager, as he and Tom Swift walked about the big fire-fighting airship Lucifer, which had been rolled outside the hangar. "But still I think she'll take it, especially since you've tuned up the motor so it's at least twenty per cent. more powerful than it was."

"I need you with us," said Tom. "I want your expert opinion on the effect the new chemicals have on the flames."

"Trust Tom Swift for that!" cried Ned. "If he says his aircraft will do the trick, it positively will."

"You are in keeping us cheerful. And we may need you to bless things if there's a slip-up anywhere," laughed Tom, for Mr. Damon had been invited to be one of the party.

The work of getting the big airship ready for what was to be a conclusive test of her fire-fighting abilities from the clouds proceeded rapidly. As has been related, Tom had perfected, with the help of Mr. Baxter, a combination of chemicals which was effective in putting out a fire when dropped into the blaze from above. Quantities of this combination had been stored in metal containers which Tom had at first styled "bombs," but which he now called "aerial grenades."

These improvements had to do with the releasing of the bombs, or, in this case, grenades. It is not easy to drop or throw something from a swiftly moving airship so that it will hit an object on the ground. During the war aviators had to train for some time before becoming even approximately accurate.

To accomplish this it was necessary to take into consideration the speed of the airship, its height above the ground, the velocity of the wind, the weight of the grenades, and other things of this sort. But by an intricate mathematical process Tom solved the problem, so that it was only necessary to set certain pointers and levers along a slide rule in the cockpit of the craft. Then when the releasing catch was pressed, the grenades would drop down just about where they were most needed.

"The doctor will know tomorrow, will he?" asked Mr. Damon.

"It couldn't be helped," said Ned. "We'll hope for the best."

"Bless my prosecuting attorney, no!" exclaimed Mr. Damon. "Those are the slickest scoundrels I ever tackled! They're like a flea. Once you think you have them where you want them, and they're on the other side of the table, skipping around."

"Don't say that!" exclaimed Tom. "Once I get this fire matter off my hands, I'm going to tackle the problem myself. We'll either make those fellows sorry they ever meddled in this matter, or we'll get up a new combination of dyes that will put them out of business!"

"Well, Rad, I'll expect to see you up and around when I get back," said Tom to his old servant, as he stepped into the sick room to say goodbye.

"Yes. I'm going to try out a new scheme of mine--the fire extinguisher, you know."

"Yes, Rad, I'm sorry to say, it's the same one."

"Of course you will," declared Tom, but his heart sank when he saw Mrs. Baggert remove the bandages and he caught sight of Rad's burned face and the eyes that had to be kept closed if ever they were again to look on the sunshine and flowers. "And when I come back, Rad, I'll stage a little fire for your benefit, and show you how quickly I can put it out."

"Of course, Rad!"

"Oh, don't talk like that!" cried Tom, as cheerfully as he could. "You've got a lot of work in you yet, Rad. Hasn't he, Koku?" and the young inventor appealed to the giant, who seldom left the side of his former enemy.

"That's the way to talk!" exclaimed Tom, and he laughed a little though his heart was far from light.

As Tom had feared, the Lucifer staggered a bit in "taking off" late that afternoon when the start was made for the distant city of Denton, where the first real test was to be made under the supervision and criticism of the fire department. But once the craft was aloft she rode on a level keel.

However, all went well, and then the course was straightened for the distant city.

"Yes. And I wish I had time to stop and see Mary, but I haven't. It's getting dark fast, and we ought to arrive at our destination early in the morning. The test has been set by the committee for ten o'clock."

"Look, Tom!" cried the eccentric man. "See that light in the sky!"

"It is a fire!" shouted Mr. Baxter. "And it's in Newmarket, if I'm any judge."

CHAPTER XXII

While Tom Swift was loading the Lucifer for her trip and the fire extinguishing test to occur the next morning, quite a different scene was taking place in the home of Jasper Blake, the uncle of Mary Nestor, where she had gone to spend a few weeks.

"Yes, Aunt, I'm all ready," Mary answered. "But I may be a bit late getting home."

"I promised Uncle Barton I'd stop and call on him at his office," Mary replied. "He has something he wants me to take home to mother when I go tomorrow."

"Yes, mother wrote that she and dad were getting a bit lonesome," the girl casually replied, as she adjusted her veil.

"I thought Tom was going to call and take you home in his airship, Mary," went on her relative.

"No," answered Mrs. Blake. "Though you might tell him to stop poking fun at your Uncle Jasper for having invested money in the Landmark Building. It's getting on your Uncle Jasper's nerves," she added.

"Please do," urged Mary's aunt, and then the girl left.

The girl was pleased with the results of her shopping, and at the close of the afternoon she stopped at the Landmark Building and was soon being shot up in the elevator to the floor where Barton Keith had his offices.

"Ah, Mary! Come in!" exclaimed Mr. Keith, welcoming Tom Swift's sweetheart. "It is so late I was afraid you weren't coming, and I was about to close the office and go home."

"No, I still had a few things to do. One was to write a letter to your Uncle Jasper, telling him I had heard of another fire trap that was open to investors."

"Ha! Ha!" laughed Uncle Barton. "He made fun of me for going on the undersea search with Tom Swift. But I made good on that, and that's more than he can say about his Landmark Building deal!"

"They are trying to make it fireproof," answered her uncle. "It's rather late to try that now, but they've got either to do it or stand a big increase in insurance rates. I'm glad I'm out of it. But now, Mary, take an easy chair until I finish some work, and then I'll walk out with you.

Suddenly there was more commotion than usual, followed by the sound of broken glass. Then came a cry of:

Mary sprang to her feet with a gasp of alarm, and her uncle rushed past her to the door leading into the hall outside his offices. As he opened the door a cloud of smoke rushed toward him and Mary, causing them to choke and gasp.

"It probably is only a slight blaze among some of the material the workmen are using," he said. "Come, Mary, we'll get out."

Mr. Keith rang the elevator buzzer several times, but when no car came up the shaft in response to his summons he turned to his niece and said:

"Oh, indeed I can walk!" said Mary. "Let's hurry out!"

And then, as they stood there, up the elevator shafts, which were veritable chimneys, came more hot smoke, mingled with sparks of fire.

CHAPTER XXIII

"Uncle! Uncle Barton!" faltered Mary, as she clung to Mr. Keith. "Can't we get down the stairs?"

"And won't the elevators come for us?"

"Then we must try the fire escapes!" exclaimed Mary, and she started toward the front window, pulling her uncle across the room after her.

"No fire escapes!" The girl turned paler than before.

"Oh, but Uncle Barton! can't we do something?" cried Mary. "There must be some way out! Let's try the elevators again, or the stairs!"

"We may have a chance!" he cried, and he rushed out. "Hurry!"

"Let's try the stairs!" suggested Mary. "They seem to be free now."

"Back, Mary! Back!" cried Mr. Keith, and he dragged the impetuous girl with him to their own corridor, and back into his offices which, for the time being, were comparatively free from the choking vapor.

Her uncle shook his head. Then he opened the window and looked out. As he did so there arose from the streets below the cries of many voices, mingled with the various sounds of fire apparatus -the whistles of engines, the clang of gongs, and the puffing of steamers.

"There isn't a life net made, nor men who could retain it, to hold up a person jumping from the tenth story," said her uncle. "Our only chance is to wait for them to subdue the fire."

Uncle and niece faced each other. Trapped indeed they were, unless the fire, which was now raging all through the building, with the stairs and elevator shafts as a center. could be subdued. That the city fire department was doing its best was not to be doubted.

Mary gave a gasp. Her uncle thought she was going to burst into tears, but she bravely conquered herself and faced him with what was meant to be a smile. But it is difficult to smile with quivering lips, and Mary soon gave up the attempt.

"It's nearly full," he said.

"Yes, but it will serve to keep our handkerchiefs wet so we can breathe through them if the smoke gets too thick," was his reply.

"Yes," agreed her uncle. "It's getting worse." Hardly had he spoken when there came a rush of feet in the corridor outside his office door. Then a voice exclaimed:

"It can't be possible!" said another voice. "Something must be done! Help! Help! Take us out of here!"

"Isn't there any way out of this fire trap?" cried one of the men. "Are there any fire escapes at your windows?"

"This is all your fault, Melling!" cried the smaller of the two men, whose voice, in loudness and depth of pitch, was out of all proportion to his size. "All your fault! I told you we should have those new fire escapes!"

"But it isn't, Melling! It isn't!" yelled the other.

"Don't do that," said Mr. Keith, coming over to close the casement. "They can't hear you down below, and opening the window will only fill this place with smoke. Are you Field and Melling?"

"It is a pretty poor specimen of a modern building," said Mr. Keith. "You have offices here, haven't you?" he went on. "I remember to have seen your names on the directory."

"You can't go any farther," said Mr. Keith. "All there is to do is to wait for the firemen."

Meanwhile Tom and his companions in the airship had seen the red glow in the evening sky, and in another minute the young inventor had turned his craft more directly toward it.

"Looks as if that was afire," said Ned quickly. "Hasn't some relative of Mary's an office there, Tom?"

"What are you going to do?" yelled Mr. Damon, as he saw the young inventor head directly toward a spouting mushroom of flame, which showed that the fire had broken through the roof. "What are you going to do?"

CHAPTER XXIV

Once it became evident to the occupants of the airship what Tom Swift's plans were, they all prepared to help him. Previous to the trip certain duties had been assigned to each one, duties which were to be exercised when Tom gave the exhibition of his new aerial fire-fighting apparatus at the set fire before the fire department of Denton.

So far the flames had confined themselves to this central part of the big structure, but it was only a question of time when they would spread out on all sides, licking up the remainder of the pile. And, for the most part, the firemen on the ground were at a great disadvantage.

This was the situation, then, when Tom in his airship loaded with fire-extinguishing chemicals headed for the blaze. And this, also, was the desperate situation that confronted Mary Nestor and her uncle, Barton Keith, as well as Amos Field and Jason Melling. Those unscrupulous and cowardly men were in a veritable panic of fear, which contrasted strangely with the calm, resigned attitude of Mary and her uncle.

"Jump from the window!" cried Melling.

"A chance? How?" asked Field. "Listen to that!"

"We can only wait," said Mr. Keith, and he wet Mary's handkerchief in the water and handed it to her to bind over her face.

"All ready," was the answer. "You only have to give the word when you want us to let go."

"He means to let go the extinguisher grenades," said Mr. Baxter. "Shall we let them all go at once, Tom?" asked the chemist.

"That's the idea!" cried Ned. "Well, give us the word when you're ready, Tom."

The flames were mounting higher and higher above the ill-fated Landmark Building. It was a "land-mark" now, for miles around--a fearsome mark, indeed.

"Bless my thermometer, you're right!" exclaimed Mr. Damon. "I don't see how any one could live in that furnace."

And it was to this fact--that the fire was rushing up the stairway and elevator shafts as up a chimney--that Mary and her uncle, as well as Field and Melling, owed their temporary safety.

"But they'll hear of it," declared Ned, when Tom voiced this idea to his chum.

"Getting close, Tom!" called Ned, as they could all feel the heat of the conflagration in the Landmark Building, which now seemed doomed.

"No, I'll have to keep pretty well up," was the answer. "There's a current of air over that fire which might turn us turtle."

It was now almost time to act. In another few seconds they would be sailing directly into the path of the up-spouting flames. Realizing that to do this at too low an elevation would result in disaster, Tom sent his craft upward at a sharp angle. Then he turned to call to his companions.

"All set and ready!" answered Ned, and the others signified their attention to the command that soon was to be given.

Straight and true as an arrow she headed for the fiery pillar! Hotter and hotter grew the air! The darkness of the night was lighted by the awful fire, which rendered objects in the street clear and distinct. But Tom and his friends had little time for such observation.

"All ready!" shouted Ned.

There was a blast as from a furnace seventy times heated, a choking and gasping for breath on the part of the occupants of the airship, a shriveling, as it seemed, of the naked flesh, and then, when it appeared that all of them must be engulfed in the great heat, the airship passed out of the zone of fire.

"Good work, Tom! Good work!"

"I'm going to try!" declared Tom.

"It will not be so bad this time," observed Ned. "The fire is half out now. Tom's stuff did the trick!"

"Give her all we have!" yelled Tom, as, once more, he prepared to cross the zone of fire.

Once more the Lucifer swept over the burning building. Down shot the remaining grenades, falling into the mass of flames and bursting, though the reports could not be heard because of the tumult in the streets below. For the firemen and spectators had seen the sudden dying down of the fire, they had caught sight of a shadowy shape in the night, hovering over the blazing building, and they wondered what it all meant.

"That settles it!" answered Ned. "There isn't fire enough now to broil a beefsteak!"

"Well," observed Tom, as he saw how effectively he had smothered the great fire, "it's of no use to go on now. I haven't an ounce of chemical left on board. I can't give the demonstration that I planned for tomorrow."

"Perhaps. I hope so. But we may as well land and see from the ground the effect of our work. I'd also like to inquire if any one was hurt. Let's go down."

"What did you do that put out the fire?" demanded the chief of the Newmarket department, as he rushed up with a crowd of others when Tom and his friends alighted.

"A few grenades! Say, you must have turned a whole river of them loose!" cried the delighted chief. "It doused the fire quicker than I ever saw one put out in all my life!"

"Yes, a few," answered a policeman, who was trying to keep the crowd back from the airship. "They're bringing them out now."

"No. But some of them are badly hurt," the officer answered. "There was one young lady and a man named Barton Keith--"

But at that moment there was a stir in the crowd about the building, in which only a little fire flow remained, and through the throng came a disheveled and smoke-blackened young lady and a man whose clothing was also greatly disarrayed.

"Tom!" gasped Mary Nestor. "How did you get here?"

"I was in Uncle Barton's office when the fire broke out," answered Mary, "and we were trapped. We had to stay there, with two men from the floor above."

Two stretchers, on which lay inert forms, were borne through the now silent crowd by firemen and police officers, and taken to waiting ambulances.

"I should say it was sudden!" cried the enthusiastic local chief. "It was the chemicals from this young man's airship that did the trick!"

"Yes," was the answer. "I was on my way to give a test tomorrow in Denton when I saw this fire. I didn't know you were in it, though, Mary."

When Field and Melling, whose rash conduct had caused them to be severely but not fatally burned, had been taken to a hospital and the fire was declared to be practically out, Tom made arrangements to leave his airship in the city field all night.

"Of course!" said Uncle Jasper himself, who had arrived on the scene, attracted to the fire by the news that his niece and Mr. Keith were in danger. "Lots of room! Come along! We'll celebrate your rescue

Only the central portion of the structure, the stairs and elevator shafts, were burned away. The strong upward draft had kept the fire from spreading much to either side.

It was the day following the night of excitement, and Tom and his friends, at the invitation of the fire department of Newmarket, were inspecting what was left of the Landmark Building --and there was considerable left--though access to the upper floors was to be had only by ladders, down which Mary and her uncle, Barton Keith, had been carried.

"Bless my fountain pen! nothing is burned here," cried the eccentric man.

"It was hot enough as it was," answered Tom, with a grim laugh.

An exclamation from Mr. Baxter attracted the attention of all in Mr. Keith's office. The chemist picked up from the floor a bundle of papers.

CHAPTER XXV

"What's that? Your dye formulae here in my office?" cried Mr. Keith, for he had heard something of the chemist's loss, though he did not directly associate Field and Melling with it.

"But how did they get here?" asked the young inventor. "I know that Field and Melling had offices in this building. They were starting a new dye concern, and, though Mr. Baxter and I suspected them of having stolen his secret, we couldn't prove it."

"I'm glad I could render you that service," said the young inventor. "And I had no idea, when I dropped the chemicals, that I was saving someone even more valuable than your secret formulae," and they all knew he referred to Mary Nestor.

As Mr. Baxter had suspected, Field and Melling had, indeed, robbed him of his dye formulae papers. They learned that he possessed them, and they invited him to a night conference with the purpose of robbing him. The fire in their factory was an accident, of which they took advantage to make it appear that the chemist lost his papers in the blaze. But they had taken them, and though they did not mean to leave poor Baxter to his fate, that would have been the result of their selfish action had not Tom and Ned come to the rescue. And it was of this "putting over" that Field and Melling had boasted, the time Tom overheard their talk at Meadow Inn.

As for the Landmark Building, while badly damaged, it would have been worse burned but for Tom's prompt action. And though he was more than glad that he had been on hand, he rather regretted that he could not give the test for which he had set out.

But, as it developed, nothing could have been more opportune than Tom's action, for word of his quenching a bigger blaze than he would have had to encounter in the official test reached the Denton fire department. As a result there was a conference, and, after only a nominal showing of his apparatus, it was adopted by a unanimous vote.

He and his companions went in the Lucifer, minus, now, the big load of chemicals, and on landing near the hangar Tom was surprised to see Koku the giant running toward him. The big man showed every symptom of great excitement as he cried:

"Who sees the light of day?" asked the young inventor.

"Oh, I'm so glad! So thankful!" cried Tom. "How I've wished for this! Is it really true, Koku?"

When Tom entered the room where Rad had been kept in the dark ever since the explosion, the colored man looked at his master with seeing eyes, though the apartment was still but dimly lighted.

"You won't have to, Rad!" cried Tom joyfully. "My chemical extinguisher is completed, and you did your share in making it a success. But I never would have felt like claiming credit for it if you had been--had been left in the dark."

"Huh! Lazy!" retorted the big man. "I show you--black coon!"

Of course it would be too much to hope that Koku and Eradicate never again quarreled, but for a long time their warm friendship was a thing at which to marvel, considering the past.

"Settles what, Tom?"

"Yes, and he has had wonderful success with that. But what are you going to do now, Tom? What new line of endeavor are you going to aim at?"

"I am now going," he said, with a grin, "to see somebody on private business."

"I am," said Tom.

End of Project Gutenberg's Etext of Tom Swift Among The Fire Fighters

Uniform Style of Binding. Individual Colored Wrappers. Every Volume Complete in Itself.

TOM SWIFT AND HIS MOTOR CYCLE TOM SWIFT AND HIS MOTOR BOAT TOM SWIFT AND HIS AIRSHIP TOM SWIFT AND HIS SUBMARINE BOAT TOM SWIFT AND HIS ELECTRIC RUNABOUT TOM SWIFT AND HIS WIRELESS MESSAGE TOM SWIFT AMONG THE DIAMOND MAKERS TOM SWIFT IN THE CAVES OF ICE TOM SWIFT AND HIS SKY RACER TOM SWIFT AND HIS ELECTRIC RIFLE TOM SWIFT IN THE CITY OF GOLD TOM SWIFT AND HIS AIR GLIDER TOM SWIFT IN CAPTIVITY TOM SWIFT AND HIS WIZARD CAMERA TOM SWIFT AND HIS GREAT SEARCHLIGHT TOM SWIFT AND HIS GIANT CANNON TOM SWIFT AND HIS PHOTO TELEPHONE TOM SWIFT AND HIS AERIAL WARSHIP TOM SWIFT AND HIS BIG TUNNEL TOM SWIFT IN THE LAND OF WONDERS TOM SWIFT AND HIS WAR TANK TOM SWIFT AND HIS AIR SCOUT TOM SWIFT AND HIS UNDERSEA SEARCH TOM SWIFT AMONG THE FIRE FIGHTERS TOM SWIFT AND HIS ELECTRIC LOCOMOTIVE TOM SWIFT AND HIS FLYING BOAT TOM SWIFT AND HIS GREAT OIL GUSHER TOM SWIFT AND HIS CHEST OF SECRETS TOM SWIFT AND HIS AIRLINE EXPRESS

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In company with his uncles, one a mighty hunter and the other a noted scientist, Don Sturdy travels far and wide, gaining much useful knowledge and meeting many thrilling adventures.

An engrossing tale of the Sahara Desert, of encounters with wild animals and crafty Arabs.

Don's uncle, the hunter, took an order for some of the biggest snakes to be found in South America--to be delivered alive!

A fascinating tale of exploration and adventure in the Valley of Kings in Egypt.

A great polar blizzard nearly wrecks the airship of the explorers.

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This story is just full of exciting and fearful experiences on the sea.

A thrilling story of adventure in darkest Africa. Don is carried over a mighty waterfall into the heart of gorilla land.

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A new series for boys giving full details of radio work, both in sending and receiving--telling how small and large amateur sets can be made and operated, and how some boys got a lot of fun and adventure out of what they did. Each volume from first to last is so thoroughly fascinating, so strictly up-to-date and accurate, we feel sure all lads will peruse them with great delight.

THE RADIO BOYS' FIRST WIRELESS THE RADIO BOYS AT OCEAN POINT THE RADIO BOYS AT THE SENDING STATION THE RADIO BOYS AT MOUNTAIN PASS THE RADIO BOYS TRAILING A VOICE THE RADIO BOYS WITH THE FOREST RANGERS THE RADIO BOYS WITH THE ICEBERG PATROL THE RADIO BOYS WITH THE FLOOD FIGHTERS THE RADIO BOYS ON SIGNAL ISLAND THE RADIO BOYS IN GOLD VALLEY

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RALPH IN THE SWITCH TOWER; Or, Clearing the Track.

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The club members went into camp on the edge of a beautiful lake. Here they had rousing good times swimming, boating and around the campfire. They fell in with a mysterious old man known as The Hermit of Triangle Island. Nobody knew his real name or where he came from until the propounding of a riddle solved these perplexing questions.

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