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Tom Swift And His Submarine Boat

by Victor Appleton

June, 1997  [Etext #949]


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TOM SWIFT AND HIS SUBMARINE BOAT
or
Under the Ocean for Sunken Treasure

by
VICTOR APPLETON



CONTENTS
    I  News of a Treasure Wreck
   II  Finishing the Submarine
  III  Mr. Berg Is Astonished
   IV  Tom Is Imprisoned
    V  Mr. Berg Is Suspicious
   VI  Turning the Tables
  VII  Mr. Damon Will Go
 VIII  Another Treasure Expedition
   IX  Captain Weston's Advent
    X  Trial of the Submarine
   XI  On the Ocean Bed
  XII  For a Breath of Air
 XIII  Off for the Treasure
  XIV  In the Diving Suits
   XV  At the Tropical Island
  XVI  "We'll Race You For It!"
 XVII  The Race
XVIII  The Electric Gun
  XIX  Captured
   XX  Doomed to Death
  XXI  The Escape
 XXII  At the Wreck
XXIII  Attacked by Sharks
 XXIV  Ramming the Wreck
  XXV  Home with the Gold






TOM SWIFT AND HIS SUBMARINE BOAT




Chapter One

News of a Treasure Wreck


There was a rushing, whizzing, throbbing noise in the air.
A great body, like that of some immense bird, sailed along,
casting a grotesque shadow on the ground below.  An elderly
man, who Was seated on the porch of a large house, started
to his feet in alarm.

"Gracious goodness! What was that, Mrs. Baggert?" he
called to a motherly-looking woman who stood in the doorway.
"What happened?"

"Nothing much, Mr. Swift," was the calm reply "I think
that was Tom and Mr. Sharp in their airship, that's all. I
didn't see it, but the noise sounded like that of the Red Cloud."

"Of course! To be sure!" exclaimed Mr. Barton Swift, the
well-known inventor, as he started down the path in order to
get a good view of the air, unobstructed by the trees. "Yes,
there they are," he added. "That's the airship, but I didn't
expect them back so soon. They must have made good time from
Shopton. I wonder if anything can be the matter that they
hurried so?"

He gazed aloft toward where a queerly-shaped machine was
circling about nearly five hundred feet in the air, for the
craft, after Swooping down close to the house, had ascended
and was now hovering just above the line of breakers that
marked the New Jersey seacoast, where Mr. Swift had taken up
a temporary residence.

"Don't begin worrying, Mr. Swift," advised Mrs. Baggert,
the housekeeper. "You've got too much to do, if you get that
new boat done, to worry."

"That's so. I must not worry. But I wish Tom and Mr. Sharp
would land, for I want to talk to them."

As if the occupants of the airship had heard the words of
the aged inventor, they headed their craft toward earth. The
combined aeroplane and dirigible balloon, a most wonderful
traveler of the air, swung around, and then, with the
deflection rudders slanted downward, came on with a rush.
When near the landing place, just at the side of the house,
the motor was stopped, and the gas, with a hissing noise,
rushed into the red aluminum container. This immediately
made the ship more buoyant and it landed almost as gently as
a feather.

No sooner had the wheels which formed the lower part of
the craft touched the ground than there leaped from the
cabin of the Red Cloud a young man.

"Well, dad!" he exclaimed. "Here we are again, safe and
sound. Made a record, too. Touched ninety miles an hour at
times--didn't we, Mr. Sharp?"

"That's what," agreed a tall, thin, dark-complexioned man,
who followed Tom Swift more leisurely in his exit from the
cabin. Mr. Sharp, a veteran aeronaut, stopped to fasten guy
ropes from the airship to strong stakes driven into the
ground.

"And we'd have done better, only we struck a hard wind
against us about two miles up in the air, which delayed us,"
went on Tom. "Did you hear us coming, dad?"

"Yes, and it startled him," put in Mrs. Baggert. "I guess
he wasn't expecting you."

"Oh, well, I shouldn't have been so alarmed, only I was
thinking deeply about a certain change I am going to make in
the submarine, Tom. I was day-dreaming, I think, when your
ship whizzed through the air. But tell me, did you find
everything all right at Shopton? No signs of any of those
scoundrels of the Happy Harry gang having been around?" and
Mr. Swift looked anxiously at his son.

"Not a sign, dad," replied Tom quickly. "Everything was
all right. We brought the things you wanted. They're in the
airship. Oh, but it was a fine trip. I'd like to take
another right out to sea."

"Not now, Tom," said his father. "I want you to help me.
And I need Mr. Sharp's help, too. Get the things out of the
car, and we'll go to the shop."

"First I think we'd better put the airship away," advised
Mr. Sharp. "I don't just like the looks of the weather, and,
besides, if we leave the ship exposed we'll be sure to have
a crowd around sooner or later, and we don't want that."

"No, indeed," remarked the aged inventor hastily. "I don't
want people prying around the submarine shed. By all means
put the airship away, and then come into the shop."

In spite of its great size the aeroplane was easily
wheeled along by Tom and Mr. Sharp, for the gas in the
container made it so buoyant that it barely touched the
earth. A little more of the powerful vapor and the Red
Cloud would have risen by itself. In a few minutes the
wonderful craft, of which my readers have been told in
detail in a previous volume, was safely housed in a large
tent, which was securely fastened.

Mr. Sharp and Tom, carrying some bundles which they had
taken from the car, or cabin, of the craft, went toward a
large shed, which adjoined the house that Mr. Swift had
hired for the season at the seashore. They found the lad's
father standing before a great shape, which loomed up dimly
in the semi-darkness of the building. It was like an immense
cylinder, pointed at either end, and here and there were
openings, covered with thick glass, like immense, bulging
eyes. From the number of tools and machinery all about the
place, and from the appearance of the great cylinder itself,
it was easy to see that it was only partly completed.

"Well, how goes it, dad?" asked the youth, as he deposited
his bundle on a bench. "Do you think you can make it work?"

"I think so, Tom. The positive and negative plates are
giving me considerable trouble, though. But I guess we can
solve the problem. Did you bring me the galvanometer?"

"Yes, and all the other things," and the young inventor
proceeded to take the articles from the bundles he carried.

Mr. Swift looked them over carefully, while Tom walked
about examining the submarine, for such was the queer craft
that was contained in the shed.  He noted that some progress
had been made on it since he had left the seacoast several
days before to make a trip to Shopton, in New York State,
where the Swift home was located, after some tools and
apparatus that his father wanted to obtain from his workshop
there.

"You and Mr. Jackson have put on several new plates,"
observed the lad after a pause.

"Yes," admitted his father. "Garret and I weren't idle,
were we, Garret?" and he nodded to the aged engineer, who
had been in his employ for many years.

"No; and I guess we'll soon have her in the water, Tom,
now that you and Mr. Sharp are here to help us," replied
Garret Jackson.

"We ought to have Mr. Damon here to bless the submarine
and his liver and collar buttons a few times," put in Mr.
Sharp, who brought in another bundle. He referred to an
eccentric individual Who had recently made an airship voyage
with himself and Tom, Mr. Damon's peculiarity being to use
continually such expressions as: "Bless my soul! Bless my
liver!"

"Well, I'll be glad when we can make a trial trip," went
on Tom. "I've traveled pretty fast on land with my motor-
cycle, and we certainly have hummed through the air. Now I
want to see how it feels to scoot along under water."

"Well, if everything goes well we'll be in position to
make a trial trip inside of a month," remarked the aged
inventor. "look here, Mr. Sharp, I made a change in the
steering gear, which I'd like you and Tom to consider."

The three walked around to the rear of the odd-looking
structure, if an object shaped like a cigar can be said to
have a front and rear, and the inventor, his son, and the
aeronaut were soon deep in a discussion of the
technicalities connected with under-water navigation.

A little later they went into the house, in response to a
summons from the supper bell, vigorously rung by Mrs.
Baggert. She was not fond of waiting with meals, and even
the most serious problem of mechanics was, in her
estimation, as nothing compared with having the soup get
cold, or the possibility of not having the meat done to a
turn.

The meal was interspersed with remarks about the recent
airship flight of Tom and Mr. Sharp, and discussions about
the new submarine. This talk went on even after the table
was cleared off and the three had adjourned to the sitting-
room. There Mr. Swift brought out pencil and paper, and soon
he and Mr. Sharp were engrossed in calculating the pressure
per square inch of sea water at a depth of three miles.

"Do you intend to go as deep as that?" asked Tom, looking
up from a paper he was reading.

"Possibly," replied his father; and his son resumed his
perusal of the sheet.

"Now," went on the inventor to the aeronaut, "I have
another plan. In addition to the positive and negative
plates which will form our motive power, I am going to
install forward and aft propellers, to use in case of
accident."

"I say, dad! Did you see this?" suddenly exclaimed Tom,
getting up from his chair, and holding his finger on a
certain place in the page of the paper.

"Did I see what?" asked Mr. Swift.

"Why, this account of the sinking of the treasure ship."

"Treasure ship? No. Where?"

"Listen," went on Tom. "I'll read it: 'Further advices
from Montevideo, Uruguay, South America, state that all hope
has been given up of recovering the steamship Boldero, which
foundered and went down off that coast in the recent gale.
Not only has all hope been abandoned of raising the vessel,
but it is feared that no part of the three hundred thousand
dollars in gold bullion which she carried will ever be
recovered. Expert divers who were taken to the scene of the
wreck state that the depth of water, and the many currents
existing there, due to a submerged shoal, preclude any
possibility of getting at the hull. The bullion, it is
believed, was to have been used to further the interests of
a certain revolutionary faction, but it seems likely that
they will have to look elsewhere for the sinews of war.
Besides the bullion the ship also carried several cases of
rifles, it is stated, and other valuable cargo. The crew and
what few passengers the Boldero carried were, contrary to
the first reports, all saved by taking to the boats. It
appears that some of the ship's plates were sprung by the
stress in which she labored in a storm, and she filled and
sank gradually.' There! what do you think of that, dad?"
cried Tom as he finished.

"What do I think of it? Why, I think it's too bad for the
revolutionists, Tom, of course."

"No; I mean about the treasure being still on board the
ship. What about that?"

"Well, it's likely to stay there, if the divers can't get
at it. Now, Mr. Sharp, about the propellers--"

"Wait, dad!" cried Tom earnestly.

"Why, Tom, what's the matter?" asked Mr. Swift in some
surprise.

"How soon before we can finish our submarine?" went on
Tom, not answering the question.

"About a month. Why?"

"Why? Dad, why can't we have a try for that treasure? It
ought to be comparatively easy to find that sunken ship off
the coast of Uruguay. In our submarine we can get close up
to it, and in the new diving suits you invented we can get
at that gold bullion. Three hundred thousand dollars! Think
of it, dad! Three hundred thousand dollars! We could easily
claim all of it, since the owners have abandoned it, but we
would be satisfied with half. Let's hurry up, finish the
submarine, and have a try for it."

"But, Tom, you forget that I am to enter my new ship in
the trials for the prize offered by the United States
Government."

"How much is the prize if you win it?" asked Tom.

"Fifty thousand dollars."

"Well, here's a chance to make three times that much at
least, and maybe more. Dad, let the Government prize go, and
try for the treasure. Will you?"

Tom looked eagerly at his father, his eyes shining with
anticipation. Mr. Swift was not a quick thinker, but the
idea his son had proposed made an impression on him. He
reached out his hand for the paper in which the young
inventor had seen the account of the sunken treasure.
Slowly he read it through. Then he passed it to Mr. Sharp.

"What do you think of it?" he asked of the aeronaut

"There's a possibility," remarked the balloonist "We might
try for it. We can easily go three miles down, and it
doesn't lie as deeply as that, if this account is true. Yes,
we might try for it. But we'd have to omit the Government
contests."

"Will you, dad?" asked Tom again.

Mr. Swift considered a moment longer.

"Yes, Tom, I will," he finally decided. "Going after the
treasure will be likely to afford us a better test of the
submarine than would any Government tests. We'll try to
locate the sunken Boldero."

"Hurrah!" cried the lad, taking the paper from Mr. Sharp
and waving it in the air. "That's the stuff!  Now for a
search for the submarine treasure!"




Chapter Two

Finishing the Submarine


"What's the matter?" cried Mrs. Baggert, the housekeeper,
hurrying in from the kitchen, where she was washing the
dishes. "Have you seen some of those scoundrels who robbed
you, Mr. Swift? If you have, the police down here ought to--"

"No, it's nothing like that," explained Mr. Swift. "Tom
has merely discovered in the paper an account of a sunken
treasure ship, and he wants us to go after it, down under
the ocean."

"Oh, dear! Some more of Captain Kidd's hidden hoard, I
suppose?" ventured the housekeeper. "Don't you bother with
it, Mr. Swift. I had a cousin once, and he got set in the
notion that he knew where that pirate's treasure was. He
spent all the money he had and all he could borrow digging
for it, and he never found a penny. Don't waste your time on
such foolishness. It's bad enough to be building airships
and submarines without going after treasure."  Mrs. Baggert
spoke with the freedom of an old friend rather than a hired
housekeeper, but she had been in the family ever since Tom's
mother died, when he was a baby, and she had many
privileges.

"Oh, this isn't any of Kidd's treasure," Tom assured her.
"If we get it, Mrs. Baggert, I'll buy you a diamond ring."

"Humph!" she exclaimed, as Tom began to hug her in boyish
fashion. "I guess I'll have to buy all the diamond rings I
want, if I have to depend on your treasure for them," and
she went back to the kitchen.

"Well," went on Mr. Swift after a pause, "if we are going
into the treasure-hunting business, Tom, we'll have to get
right to work. In the first place, we must find out more
about this ship, and just where it was sunk."

"I can do that part," said Mr. Sharp. "I know some sea
captains, and they can put me on the track of locating the
exact spot. In fact, it might not be a bad idea to take an
expert navigator with us. I can manage in the air all right,
but I confess that working out a location under water is
beyond me."

"Yes, an old sea captain wouldn't be a bad idea, by any
means," conceded Mr. Swift. "Well, if you'll attend to that
detail, Mr. Sharp, Tom, Mr. Jackson and I will finish the
submarine. Most of the work is done, however, and it only
remains to install the engine and motors. Now, in regard to
the negative and positive electric plates, I'd like your
opinion, Tom."

For Tom Swift was an inventor, second in ability only to
his father, and his advice was often sought by his parent on
matters of electrical construction, for the lad had made a
specialty of that branch of science.

While father and son were deep in a discussion of the
apparatus of the submarine, there will be an opportunity to
make the reader a little better acquainted with them. Those
of you who have read the previous volumes of this series do
not need to be told who Tom Swift is. Others, however, may
be glad to have a proper introduction to him.

Tom Swift lived with his father, Barton Swift, in the
village of Shopton, New York. The Swift home was on the
outskirts of the town, and the large house was surrounded by
a number of machine shops, in which father and son, aided by
Garret Jackson, the engineer, did their experimental and
constructive work. Their house was not far from Lake
Carlopa, a fairly large body of water, on which Tom often
speeded his motor

In the first volume of this series, entitled "Tom Swift
and His Motor-Cycle," it was told how be became acquainted
with Mr. Wakefield Damon, who suffered an accident while
riding one of the speedy machines. The accident disgusted
Mr. Damon with motor-cycles, and Tom secured it for a low
price. He had many adventures on it, chief among which was
being knocked senseless and robbed of a valuable patent
model belonging to his father, which he was taking to
Albany. The attack was committed by a gang known as the
Happy Harry gang, who were acting at the instigation of a
syndicate of rich men, who wanted to secure control of a
certain patent turbine engine which Mr. Swift had invented.

Tom set out in pursuit of the thieves, after recovering
from their attack, and had a strenuous time before he
located them.

In the second volume, entitled "Tom Swift and His Motor-
Boat," there was related our hero's adventures in a fine
craft which was recovered from the thieves and sold at
auction. There was a mystery connected with the boat, and
for a long time Tom could not solve it. He was aided,
however, by his chum, Ned Newton, who worked in the Shopton
Bank, and also by Mr. Damon and Eradicate Sampson, an aged
colored whitewasher, who formed quite an attachment for Tom.

In his motor-boat Tom had more than one race with Andy
Foger, a rich lad of Shopton, who was a sort of bully. He
had red hair and squinty eyes, and was as mean in character
as he was in looks. He and his cronies, Sam Snedecker and
Pete Bailey, made trouble for Tom, chiefly because Tom
managed to beat Andy twice in boat races.

It was while in his motor-boat, Arrow, that Tom formed the
acquaintance of John Sharp, a veteran balloonist. While
coming down Lake Carlopa on the way to the Swift home, which
had been entered by thieves, Tom, his father and Ned Newton,
saw a balloon on fire over the lake. Hanging from a trapeze
on it was Mr. Sharp, who had made an ascension from a fair
ground. By hard work on the part of Tom and his friends the
aeronaut was saved, and took up his residence with the
Swifts.

His advent was most auspicious, for Tom and his father
were then engaged in perfecting an airship, and Mr. Sharp
was able to lend them his skill, so that the craft was soon
constructed.

In the third volume, called "Tom Swift and His Airship,"
there was set down the doings of the young inventor, Mr.
Sharp and Mr. Damon on a trip above the clouds. They
undertook it merely for pleasure, but they encountered
considerable danger, before they completed it, for they
nearly fell into a blazing forest once, and were later fired
at by a crowd of excited people. This last act was to effect
their capture, for they were taken for a gang of bank
robbers, and this was due directly to Andy Foger.

The morning after Tom and his friends started on their
trip in the air, the Shopton Bank was found to have been
looted of seventy-five thousand dollars. Andy Foger at once
told the police that Tom Swift had taken the money, and when
asked how he knew this, he said he had seen Tom hanging
around the bank the night before the vault was burst open,
and that the young inventor had some burglar tools in his
possession. Warrants were at once sworn out for Tom and Mr.
Damon, who was also accused of being one of the robbers, and
a reward of five thousand dollars was offered.

Tom, Mr. Damon and Mr. Sharp sailed on, all unaware of
this, and unable to account for being fired upon, until they
accidentally read in the paper an account of their supposed
misdeeds. They lost no time in starting back home, and on,
the way got on the track of the real bank robbers, who were
members of the Happy Harry gang.

How the robbers were captured in an exciting raid, how Tom
recovered most of the stolen money, and how he gave Andy
Foger a deserved thrashing for giving a false clue was told
of, and there was an account of a race in which the Red
Cloud (as the airship was called) took part, as well as
details of how Tom and his friends secured the reward, which
Andy Foger hoped to collect.

Those of you who care to know how the Red Cloud was
constructed, and how she behaved in the air, even during
accidents and when struck by lightning, may learn by reading
the third volume, for the airship was one of the most
successful ever constructed.

When the craft was finished, and the navigators were ready
to start on their first long trip, Mr. Swift was asked to go
with them. He declined, but would not tell why, until Tom,
pressing him for an answer, learned that his father was
planning a submarine boat, which he hoped to enter in some
trials for Government prizes. Mr. Swift remained at home to
work on this submarine, while his son and Mr. Sharp were
sailing above the clouds.

On their return, however, and after the bank mystery had
been cleared up, Tom and Mr. Sharp, aided Mr. Swift in
completing the submarine, until, when the present story
opens, it needed but little additional work to make the
craft ready for the water.

Of course it had to be built near the sea, as it would
have been impossible to transport it overland from Shopton.
So, before the keel was laid, Mr. Swift rented a large
cottage at a seaside place on the New Jersey coast and
there, after, erecting a large shed, the work on the
Advance, as the under-water ship was called, was begun.

It was soon to be launched in a large creek that extended
in from the ocean and had plenty of water at high tide. Tom
and Mr. Sharp made several trips back and forth from Shopton
in their airship, to see that all was safe at home and
occasionally to get needed tools and supplies from the
shops, for not all the apparatus could be moved from Shopton
to the coast.

It was when returning from one of these trips that Tom
brought with him the paper containing an account of the
wreck of the Boldero and the sinking of the treasure she
carried.

Until late that night the three fortune-hunters discussed
various matters.

"We'll hurry work on the ship," said Mr. Swift it length.
"Tom, I wonder if your friend, Mr. Damon, would care to try
how it seems under Water? He stood the air trip fairly
well."

"I'll write and ask him," answered the lad. "I'm sure
he'll go."

Securing, a few days later, the assistance of two
mechanics, whom he knew he could trust, for as yet the
construction of the Advance was a secret, Mr. Swift prepared
to rush work on the submarine, and for the next three weeks
there were busy times in the shed next to the seaside
cottage. So busy, in fact, were Tom and Mr. Sharp, that
they only found opportunity for one trip in the airship, and
that was to get some supplies from the shops at home.

"Well," remarked Mr. Swift one night, at the close of a
hard day's work, "another week will see our craft completed.
Then we will put it in the water and see how it floats, and
whether it submerges as I hope it does. But come on, Tom. I
want to lock up. I'm very tired to-night."

"All right, dad," answered the young inventor coming from
the darkened rear of the shop. "I just want to--"

Ne paused suddenly, and appeared to be listening. Then he
moved softly back to where he had come from.

"What's the matter?" asked his father in a whisper.
"What's up, Tom?"

The lad did not answer Mr. Swift, with a worried look on
his face, followed his son. Mr. Sharp stood in the door of
the shop.

"I thought I heard some one moving around back here," went
on Tom quietly.

"Some one in this shop!" exclaimed the aged inventor
excitedly. "Some one trying to steal my ideas again! Mr.
Sharp, come here! Bring that rifle! We'll teach these
scoundrels a lesson!"

Tom quickly darted hack to the extreme rear of the
building. There was a scuffle, and the next minute Tom cried
out:

"What are you doing here?"

"Ha! I beg your pardon," replied a voice. "I am looking
for Mr. Barton Swift."

"My father," remarked Tom. "But that's a queer place to
look for him. He's up front. Father, here's a man who wishes
to see you," he called.

"Yes, I strolled in, and seeing no one about I went to the
rear of the place," the voice went on. "I hope I haven't
transgressed."

"We were busy on the other side of the shop, I guess,"
replied Tom, and he looked suspiciously at the man who
emerged from the darkness into the light from a window. "I
beg your pardon for grabbing you the way I did," went on the
lad, "but I thought you were one of a gang of men we've been
having trouble with."

"Oh, that's all right," continued the man easily. "I know
Mr. Swift, and I think he will remember me. Ah, Mr. Swift,
how do you do?" he added quickly, catching sight of Tom's
father, who, with Mr. Sharp, was coming to meet the lad.

"Addison Berg!" exclaimed the aged inventor as he saw the
man's face more plainly. "What are you doing here?"

"I came to see you," replied the man. "May I have a talk
with you privately?"

"I--I suppose so," assented Mr. Swift nervously. "Come
into the house."

Mr. Berg left Tom's side and advanced to where Mr. Swift
was standing. Together the two emerged from the now fast
darkening shop and went toward the house.

"Who is he?" asked Mr. Sharp of the young inventor in a
whisper.

"I don't know," replied the lad; "but, whoever he is, dad
seems afraid of him. I'm going to keep my eyes open."




Chapter Three

Mr. Berg is Astonished


Following his father and the stranger whom the aged
inventor had addressed as Mr. Berg, Tom and Mr. Sharp
entered the house, the lad having first made sure that
Garret Jackson was on guard in the shop that contained the
sub marine.

"Now," said Mr. Swift to the newcomer, "I am at your
service. What is it you wish?"

"In the first place, let me apologize for having startled
you and your friends," began the man. "I had no idea of
sneaking into your workshop, but I had just arrived here,
and seeing the doors open I went in. I heard no one about,
and I wandered to the back of the place. There I happened to
stumble over a board--"

"And I heard you," interrupted Tom.

"Is this one of your employees?" asked Mr. Berg in rather
frigid tones.

"That is my son," replied Mr. Swift.

"Oh, I beg your pardon." The man's manner changed quickly.
"Well, I guess you did hear me, young man. I didn't intend
to hark my shins the way I did, either. You must have taken
me for a burglar or a sneak thief."

"I have been very much bothered by a gang of unscrupulous
men," said Mr. Swift, "and I suppose Tom thought it was some
of them sneaking around again."

"That's what I did," added the lad. "I wasn't going to
have any one steal the secret of the submarine if I could
help it."

"Quite right! Quite right!" exclaimed Mr. Berg. "But my
purpose was an open one. As you know, Mr. Swift, I represent
the firm of Bentley & Eagert, builders of submarine boats
and torpedoes. They heard that you were constructing a craft
to take part in the competitive prize tests of the United
States Government, and they asked me to come and see you to
learn when your ship would be ready. Ours is completed, but
we recognize that it will be for the best interests of all
concerned if there are a number of contestants, and my firm
did not want to send in their entry until they knew that you
were about finished with your ship. How about it? Are you
ready to compete?"

"Yes," said Mr. Swift slowly. "We are about ready. My
craft needs a few finishing touches, and then it will be
ready to launch."

"Then we may expect a good contest on your part,"
suggested Mr. Berg.

"Well," began the aged inventor, "I don't know about
that."

"What's that?" exclaimed Mr. Berg.

"I said I wasn't quite sure that we would compete," went
on Mr. Swift. "You see, when I first got this idea for a
submarine boat I had it in mind to try for the Government
prize of fifty thousand dollars."

"That's what we want, too," interrupted Mr. Berg with a
smile.

"But," went on Tom's father, "since then certain matters
have come up, and I think, on the whole, that we'll not
compete for the prize after all."

"Not compete for the prize?" almost shouted the agent for
Bentley & Eagert. "Why, the idea! You ought to compete. It
is good for the trade. We think we have a very fine craft,
and probably we would beat you in the tests, but--"

"I wouldn't be too sure of that," put in Tom. "You have
only seen the outside of our boat. The inside is better
yet."

"Ah, I have no doubt of that," spoke Mr. Berg, "but we
have been at the business longer than you have, and have had
more experience. Still we welcome competition. But I am very
much surprised that you are not going to compete for the
prize, Mr. Swift. Very much surprised, indeed! You see, I
came down from Philadelphia to arrange so that we could both
enter our ships at the same time. I understand there is
another firm of submarine boat builders who are going to try
for the prize, and I want to arrange a date that will he
satisfactory to all. I am greatly astonished that you are
not going to compete."

"Well, we were going to," said Mr. Swift, "only we have
changed our minds, that's all. My son and I have other
plans."

"May I ask what they are?" questioned Mr. Berg.

"You may," exclaimed Tom quickly; "but I don't believe we
can tell you. They're a secret," he added more cordially.

"Oh, I see," retorted Mr. Berg. "Well, of course I don't
wish to penetrate any of your secrets, but I hoped we could
contest together for the Government prize. It is worth
trying for I assure you--fifty thousand dollars. Besides,
there is the possibility of selling a number of submarines
to the United States. It's a fine prize."

"But the one we are after is a bigger one," Cried Tom
impetuously, and the moment he had spoken the wished he
could recall the words.

"Eh? What's that?" exclaimed Mr. Berg. "You don't mean to
say another government has offered a larger prize? If I had
known that I would not have let my firm enter into the
competition for the bonus offered by the United States.
Please tell me."

"I'm sorry," went on Tom more soberly. "I shouldn't have
spoken. Mr. Berg, the plans of my father and myself are such
that we can't reveal them now. We are going to try for a
prize, but not in competition with you. It's an entirely
different matter."

"Well, I guess you'll find that the firm of Bentley &
Eagert are capable of trying for any prizes that are
offered," boasted the agent. "We may be competitors yet."

"I don't believe so," replied Mr. Swift

"We may," repeated Mr. Berg. "And if we do, please
remember that we will show no mercy. Our boats are the
best."

"And may the best boat win," interjected Mr. Sharp.
"That's all we ask. A fair field and no favors."

"Of course," spoke the agent coldly. "Is this another son
of yours?" he asked.

"No but a good friend," replied the aged inventor. "No,
Mr. Berg, we won't compete this time. You may tell your firm
so."

"Very good," was the other's stiff reply. "Then
I will bid you good night. We shall carry off the
Government prize, but permit me to add that I
am very much astonished, very much indeed, that
you do not try for the prize. From what I have
seen of your submarine you have a very good
one, almost as good, in some respects, as ours.
I bid you good night," and with a bow the man
left the room and hurried away from the house.




Chapter Four

Tom is Imprisoned


"Well, I must say he's a cool one," remarked Tom, as the
echoes of Mr. Berg's steps died away. "The idea of thinking
his boat better than ours! I don't like that man, dad. I'm
suspicious of him. Do you think he came here to steal some
of our ideas?"

"No, I hardly believe so, my son. But how did you discover
him?"

"Just as you saw, dad. I heard a noise and went back there
to investigate. I found him sneaking around, looking at the
electric propeller plates. I went to grab him just as he
stumbled over a hoard. At first I thought it was one of the
old gang. I'm almost sure he was trying to discover
something."

"No, Tom. the firm he works for are good business men, and
they would not countenance anything like that. They are
heartless competitors, however, and if they saw a legitimate
chance to get ahead of me and take advantage, they would do
it. But they would not sneak in to steal my ideas. I feel
sure of that. Besides, they have a certain type of submarine
which they think is the best ever invented, and they would
hardly change at this late day. They feel sure of winning
the Government prize, and I'm just as glad we're not going
to have a contest."

"Do you think our boat is better than theirs?"

"Much better, in many respects."

"I don't like that man Berg, though," went on Tom.

"Nor do I," added his father. "There is something strange
about him.  He was very anxious that I should compete.
Probably he thought his firm's boat would go so far ahead of
ours that they would get an extra bonus. But I'm glad he
didn't see our new method of propulsion. That is the
principal improvement in the Advance over other types of
submarines. Well, another week and we will be ready for the
test."

"Have you known Mr. Berg long, dad?"

"Not very. I met him in Washington when I was in the
patent office. He was taking out papers on a submarine for
his firm at the same time I got mine for the Advance. It is
rather curious that he should come all the way here from
Philadelphia. merely to see if I was going to compete. There
is something strange about it, something that I can't
understand."

The time was to come when Mr. Swift and his son were to
get at the bottom of Mr. Berg's reasons, and they learned to
their sorrow that he had penetrated some of their secrets.

Before going to bed that night Tom and Mr. Sharp paid a
visit to the shed where the submarine was resting on the
ways, ready for launching. They found Mr. Jackson on guard
and the engineer said that no one had been around. Nor was
anything found disturbed.

"It certainly is a great machine," remarked the lad as he
looked up at the cigar-shaped bulk towering over his head.
"Dad has outdone himself this trip."

"It looks all right," commented Mr. Sharp. "Whether it
will work is another question."

"Yes, we can't tell until it's in the water," con ceded
Tom. "But I hope it does. Dad has spent much time and money
on it."

The Advance was, as her name indicated, much in advance of
previous submarines. There was not so much difference in
outward construction as there was in the means of propulsion
and in the manner in which the interior and the machinery
were arranged.

The submarine planned by Mr. Swift and Tom jointly, and
constructed by them, with the aid of Mr. Sharp and Mr.
Jackson, was shaped like a Cigar, over one hundred feet long
and twenty feet in diameter at the thickest part. It was
divided into many compartments, all water-tight, so that if
one or even three were flooded the ship would still be
useable.

Buoyancy was provided for by having several tanks for the
introduction of compressed air, and there was an emergency
arrangement so that a collapsible aluminum container could
be distended and filled with a powerful gas. This was to be
used if, by any means, the ship was disabled on the bottom
of the ocean. The container could be expanded and filled,
and would send the Advance to the surface.

Another peculiar feature was that the engine-room, dynamos
and other apparatus were all contained amidships. This gave
stability to the craft, and also enabled the same engine to
operate both shafts and propellers, as well as both the
negative forward electrical plates, and the positive rear
ones.

These plates were a new idea in submarine construction,
and were the outcome of an idea of Mr. Swift, with some
suggestions from his son.

The aged inventor did not want to depend on the usual
screw propellers for his craft, nor did he want to use a jet
of compressed air, shooting out from a rear tube, nor yet a
jet of water, by means of which the creature called the
squid shoots himself along. Mr. Swift planned to send the
Advance along under water by means of electricity.

Certain peculiar plates were built at the forward and aft
blunt noses of the submarine. Into the forward plate a
negative charge of electricity was sent, and into the one at
the rear a positive charge, just as one end of a horseshoe
magnet is positive and will repel the north end of a compass
needle, while the other pole of a magnet is negative and
will attract it. In electricity like repels like, while
negative and positive have a mutual attraction for each
other.

Mr. Swift figured out that if he could send a powerful
current of negative electricity into the forward plate it
would pull the boat along, for water is a good conductor of
electricity, while if a positive charge was sent into the
rear plate it would serve to push the submarine along, and
he would thus get a pulling and pushing motion, just as a
forward and aft propeller works on some ferry boats.

But the inventor did not depend on these plates alone.
There were auxiliary forward and aft propellers of the
regular type, so that if the electrical plates did not work,
or got out of order, the screws would serve to send the
Advance along.

There was much machinery in the submarine There were
gasolene motors, since space was too cramped to allow the
carrying of coal for boilers. There were dynamos, motors and
powerful pumps. Some of these were for air, and some for
water. To sink the submarine below the surface large tanks
were filled with water. To insure a more sudden descent,
deflecting rudders were also used, similar to those on an
airship. There were also special air pumps, and one for the
powerful gas, which was manufactured on board.

Forward from the engine-room was a cabin, where meals
could be served, and where the travelers could remain in the
daytime. There was also a small cooking galley, or kitchen,
there. Back of the engine-room were the sleeping quarters
and the storerooms. The submarine was steered from the
forward compartment, and here were also levers, wheels and
valves that controlled all the machinery, while a number of
dials showed in which direction they were going, how deep
they were, and at what speed they were moving, as well as
what the ocean pressure was.

On top, forward, was a small conning, or observation
tower, with auxiliary and steering and controlling apparatus
there. This was to be used when the ship was moving along
on the surface of the ocean, or merely with the deck awash.
There was a small flat deck surrounding the conning tower
and this was available when the craft was on the surface.

There was provision made for leaving the ship when it was
on the bed of the ocean. When it was desired to do this the
occupants put on diving suits, which were provided with
portable oxygen tanks. Then they entered a chamber into
which water was admitted until it was equal in pressure to
that outside. Then a steel door was opened, and they could
step out. To re-enter the ship the operation was reversed.
This was not a new feature. In fact, many submarines to-day
use it

At certain places there were thick bull's-eye windows, by
means of which the under-water travelers could look out into
the ocean through which they were moving. As a defense
against the attacks of submarine monsters there was a steel,
pointed ram, like a big harpoon. There were also a bow and a
stern electrical gun, of which more will be told later.

In addition to ample sleeping accommodations. there were
many conveniences aboard the Advance. Plenty of fresh water
could be carried, and there was an apparatus for distilling
more from the sea water that surrounded the travelers.
Compressed air was carried in large tanks, and oxygen could
be made as needed. In short, nothing that could add to the
comfort or safety of the travelers had been omitted. There
was a powerful crane and windlass, which had been installed
when Mr. Swift thought his boat might be bought by the
Government. This was to be used for raising wrecks or
recovering objects from the bottom of the ocean. Ample
stores and provisions were to be carried and, once the
travelers were shut up in the Advance, they could exist for
a month below the surface, providing no accident occurred.

All these things Tom and Mr. Sharp thought of as they
looked over the ship before turning in for the night. The
craft was made immensely strong to withstand powerful
pressure at the bottom of the ocean. The submarine could
penetrate to a depth of about three miles. Below that it was
dangerous to go, as the awful force would crush the plates,
powerful as they were.

"Well, we'll rush things to-morrow and the next day,"
observed Tom as he prepared to leave the building. "Then
we'll soon see if it works."

For the next week there were busy times in the shop near
the ocean. Great secrecy was maintained, and though
curiosity seekers did stroll along now and then, they
received little satisfaction. At first Mr. Swift thought
that the visit of Mr. Berg would have unpleasant results,
for he feared that the agent would talk about the craft, of
which he had so unexpectedly gotten a sight. But nothing
seemed to follow from his chance inspection, and it was
forgotten.

It was one evening, about a week later, that Tom was alone
in the shop. The two mechanics that had been hired to help
out in the rush had been let go, and the ship needed but a
few adjustments to make it ready for the sea.

"I think I'll just take another look at the water tank
valves," said Tom to himself as he prepared to enter the big
compartments which received the water ballast. "I want to be
sure they work properly and quickly. We've got to depend on
them to make us sink when we want to, and, what's more
important, to rise to the surface in a hurry. I've got time
enough to look them over before dad and Mr. Sharp get back."

Tom entered the starboard tank by means of an emergency
sliding door between the big compartments and the main part
of the ship. This was closed by a worm and screw gear, and
once the ship was in the water would seldom be used.

The young inventor proceeded with his task, carefully
inspecting the valves by the light of a lantern he carried.
The apparatus seemed to be all right, and Tom was about to
leave when a peculiar noise attracted his attention. It was
the sound of metal scraping on metal, and the lad's quick
and well-trained ear told him it was somewhere about the
ship.

He turned to leave the tank, but as he wheeled around his
light flashed on a solid wall of steel back of him. The
emergency outlet had been closed! He was a prisoner in the
water compartment, and he knew, from past experience, that
shout as he would, his voice could not be heard ten feet
away. His father and Mr. Sharp, as he was aware, had gone to
a nearby city for some tools, and Mr. Jackson, the engineer,
was temporarily away. Mrs. Baggert, in the house, could not
hear his cries.

"I'm locked in!" cried Tom aloud. "The worm gear must have
shut of itself. But I don't see how that could be. I've got
to get out mighty soon, though, or I'll smother. This tank
is airtight, and it won't take me long to breath up all the
oxygen there is here. I must get that slide open."

He sought to grasp the steel plate that closed the
emergency opening. His fingers slipped over the smooth,
polished surface. He was hermetically sealed up--a captive!
Blankly he set his lantern down and leaned hopelessly
against the wall of the tank.

"I've got to get out," he murmured.

As if in answer to him he heard a voice on the outside,
crying:

"There, Tom Swift! I guess I've gotten even with you now!
Maybe next time you won't take a reward away from me, and
lick me into the bargain. I've got you shut up good and
tight, and you'll stay there until I get ready to let you
out."

"Andy Foger!" gasped Tom. "Andy Foger sneaked in here and
turned the gear. But how did he get to this part of the
coast? Andy Foger, you let me out!" shouted the young
inventor; and as Andy's mocking laugh came to him faintly
through the steel sides of the submarine, the imprisoned lad
beat desperately with his hands on the smooth sides of the
tank, vainly wondering how his enemy had discovered him.




Chapter Five

Mr. Berg is Suspicious


Not for long did the young inventor endeavor to break his
way out of the water-ballast tank by striking the heavy
sides of it. Tom realized that this was worse than useless.
He listened intently, but could hear nothing. Even the
retreating footsteps of Andy Foger were inaudible.

"This certainly is a pickle!" exclaimed Tom aloud. "I
can't understand how he ever got here. He must have traced
us after we went to Shopton in the airship the last time.
Then he sneaked in here. Probably he saw me enter, but how
could he knew enough to work the worm gear and close the
door? Andy has had some experience with machinery, though,
and one of the vaults in the bank where his father is a
director closed just like this tank. That's very likely how
he learned about it. But I've got to do something else
besides thinking of that sneak, Andy. I've got to get out of
here. Let's see if I can work the gear from inside."

Before he started, almost, Tom knew that it would be
impossible. The tank was made to close from the interior of
the submarine, and the heavy door, built to withstand the
pressure of tons of water, could not be forced except by the
proper means.

"No use trying that," concluded the lad, after a tiring
attempt to force back the sliding door with his hands. "I've
got to call for help."

He shouted until the vibrations in the confined space made
his ears ring, and the mere exertion of raising his voice to
the highest pitch made his heart beat quickly. Yet there
came no response. He hardly expected that there would be
any, for with his father and Mr. Sharp away, the engineer
absent on an errand, and Mrs. Baggert in the house some
distance off, there was no one to hear his calls for help,
even if they had been capable of penetrating farther than
the extent of the shed, where the under-water craft had been
constructed.

"I've got to wait until some of them come out here,"
thought Tom. "They'll be sure to release me and make a
search. Then it will be easy enough to call to them and tell
them where I am, once they are inside the shed. But--" He
paused, for a horrible fear came over him. "Suppose they
should come--too late?" The tank was airtight. There was
enough air in it to last for some time, but, sooner or
later, it would no longer support life. Already, Tom
thought, it seemed oppressive, though probably that was his
imagination.

"I must get out!" he repeated frantically. "I'll die in
here soon."

Again he tried to shove back the steel door. Then he
repeated his cries until be was weary. No one answered him.
He fancied once he could hear footsteps in the shed, and
thought, perhaps, it was Andy, come back to gloat over him.
Then Tom knew the red-haired coward would not dare venture
back. We must do Andy the justice to say that he never
realized that he was endangering Tom's life. The bully had
no idea the tank was airtight when he closed it. He had seen
Tom enter and a sudden whim came to him to revenge himself.

But that did not help the young inventor any. There was no
doubt about it now--the air was becoming close. Tom had been
imprisoned nearly two hours, and as he was a healthy, strong
lad, he required plenty of oxygen. There was certainly less
than there had been in the tank. His head began to buzz, and
there was a ringing in his ears.

Once more he fell upon his knees, and his fingers sought
the small projections of the gear on the inside of the door
He could no more budge the mechanism than a child could open
a burglar-proof vault.

"It's no use," he moaned, and he sprawled at full length
on the floor of the tank, for there the air was purer. As he
did so his fingers touched something. He started as they
closed around the handle of a big monkey wrench. It was one
he had brought into the place with him. Imbued with new hope
be struck a match and lighted his lantern, which he had
allowed to go out as it burned up too much of the oxygen. By
the gleam of it he looked to see if there were any bolts or
nuts he could loosen with the wrench, in order to slide the
door back. It needed but a glance to show him the futility
of this.

"It's no go," he murmured, and he let the wrench fall to
the floor. There was a ringing, clanging sound, and as it
smote his ears Tom sprang up with an exclamation.

"That's the thing!" he cried. "I wonder I didn't think of
it before. I can signal for help by pounding on the sides of
the tank with the wrench. The blows will carry a good deal
farther than my voice would." Every one knows how far the
noise of a boiler shop, with hammers falling on steel
plates, can be heard; much farther than can a human voice.

Tom began a lusty tattoo on the metal sides of the tank.
At first he merely rattled out blow after blow, and then, as
another thought came to him, he adopted a certain plan. Some
time previous, when he and Mr. Sharp had planned their trip
in the air, the two had adopted a code of signals. As it was
difficult in a high wind to shout from one end of the
airship to the other, the young inventor would sometimes
pound on the pipe which ran from the pilot house of the Red
Cloud to the engine-room. By a combination of numbers,
simple messages could be conveyed. The code included a call
for help. Forty-seven was the number, but there had never
been any occasion to use it.

Tom remembered this now. At once he ceased his
indiscriminate hammering, and began to beat out regularly--
one, two, three, four--then a pause, and seven blows would
be given. Over and over again he rang out this number--forty
seven--the call for help.

"If Mr. Sharp only comes back he will hear that, even in
the house," thought poor Tom "Maybe Garret or Mrs. Baggert
will hear it, too, but they won't know what it means.
They'll think I'm just working on the submarine."

It seemed several hours to Tom that he pounded out that
cry for aid, but, as he afterward learned, it was only a
little over an hour. Signal after signal he sent vibrating
from the steel sides of the tank. When one arm tired he
would use the other. He grew weary, his head was aching, and
there was a ringing in his ears; a ringing that seemed as if
ten thousand bells were jangling out their peals, and he
could barely distinguish his own pounding.

Signal after signal he sounded. It was becoming like a
dream to him, when suddenly, as he paused for a rest, he
heard his name called faintly, as if far away.

"Tom! Tom! Where are you?"

It was the voice of Mr. Sharp. Then followed the tones of
the aged inventor.

"My poor boy! Tom, are you still alive?"

"Yes, dad! In the starboard tank!" the lad gasped out, and
then he lost his senses. When he revived he was lying on a
pile of bagging in the submarine shop, and his father and
the aeronaut were bending over him.

"Are you all right, Tom?" asked Mr. Swift.

"Yes--I--I guess so," was the hesitating answer. "Yes,"
the lad added, as the fresh air cleared his head. "I'll be
all right pretty soon. Have you seen Andy Foger?"

"Did he shut you in there?" demanded Mr. Swift.

Tom nodded.

"I'll have him arrested!" declared Mr. Swift "I'll go to
town as soon as you're in good shape again and notify the
police."

"No, don't," pleaded Tom. "I'll take care of Andy myself.
I don't really believe he knew how serious it was. I'll
settle with him later, though."

"Well, it came mighty near being serious," remarked Mr.
Sharp grimly. "Your father and I came back a little sooner
than we expected, and as soon as I got near the house I
heard your signal. I knew what it was in a moment. There
were Mrs. Baggert and Garret talking away, and when I asked
them why they didn't answer your call they said they thought
you were merely tinkering with the machinery. But I knew
better. It's the first time we ever had a use for 'forty-
seven,' Tom."

"And I hope it will be the last," replied the young
inventor with a faint smile. "But I'd like to know what Andy
Foger is doing in this neighborhood."

Tom was soon himself again and able to go to the house,
where he found Mrs. Baggert brewing a big basin of catnip
tea, under the impression that it would in some way be good
for his. She could not forgive herself for not having
answered his signal, and as for Mr. Jackson, he had started
for a doctor as soon as he learned that Tom was shut up in
the tank. The services of the medical man were canceled by
telephone, as there was no need for him, and the engineer
came back to the house.

Tom was fully himself the next day, and aided his father
and Mr. Sharp in putting the finishing touches to the
Advance. It was found that some alteration was required in
the auxiliary propellers, and this, much to the regret of
the young inventor, would necessitate postponing the trial a
few days.

"But we'll have her in the water next Friday." promised
Mr. Swift.

"Aren't you superstitious about Friday?" asked the
balloonist.

"Not a bit of it," replied the aged inventor. "Tom," he
added, "I wish you would go in the house and get me the roll
of blueprints you'll find on my desk."

As the lad neared the cottage he saw, standing in front of
the place, a small automobile. A man had just descended
from it, and it needed but a glance to show that he was Mr.
Addison Berg.

"Ah, good morning, Mr. Swift," greeted Mr. Berg. "I wish
to see your father, but as I don't wish to lay myself open
to suspicions by entering the shop, perhaps you will ask him
to step here."

"Certainly," answered the lad, wondering why the agent had
returned. Getting the blueprints, and asking Mr. Berg to sit
down on the porch, Tom delivered the message.

"You come back with me, Tom," said his father. "I want you
to be a witness to what he says. I'm not going to get into
trouble with these people."

Mr. Berg came to the point at once.

"Mr. Swift," he said, "I wish you would reconsider your
determination not to enter the Government trials. I'd like
to see you compete. So would my firm."

"There is no use going over that again," replied the aged
inventor. "I have another object in view now than trying for
the Government prize. What it is I can't say, but it may
develop in time--if we are successful," and he looked at
his son, smiling the while.

Mr. Berg tried to argue, but it was of no avail Then he
changed his manner, and said:

"Well, since you won't, you won't, I suppose. I'll go back
and report to my firm.  Have you anything special to do this
morning?" he went on to Tom.

"Well, I can always find something to keep me busy,"
replied the lad, "but as for anything special--"

"I thought perhaps you'd like to go for a trip in my
auto," interrupted Mr. Berg. "I had asked a young man who is
stopping at the same hotel where I am to accompany me, but
he has unexpectedly left, and I don't like to go alone. His
name was--let me see. I have a wretched memory for names,
but it was something like Roger or Moger."

"Foger!" cried Tom. "Was it Andy Foger?"

"Yes, that was it. Why, do you know him?" asked Mr. Berg
in some surprise.

"I should say so," replied Tom. "He was the cause of what
might have resulted in something serious for me," and the
lad explained about being imprisoned in the tank.

"You don't tell me!" cried Mr. Berg. "I had no idea he was
that kind of a lad. You see, his father is one of the
directors of the firm by whom I am employed. Andy came from
home to spend a few weeks at the seaside, and stopped at the
same hotel that I did. He went off yesterday afternoon, and
I haven't seen him since, though he promised to go for a
ride with me. He must have come over here and entered your
shop unobserved. I remember now he asked me where the
submarine was being built that was going to compete with our
firm's, and I told him. I didn't think he was that kind of
a lad. Well, since he's probably gone back home, perhaps you
will come for a ride with me, Tom."

"I'm afraid I can't go, thank you," answered the lad. "We
are very busy getting our submarine in shape for a trial.
But I can imagine why Andy left so hurriedly. He probably
learned that a doctor had been summoned for me, though, as
it happened, I didn't need one. But Andy probably got
frightened at what he had done, and left. I'll make him
more sorry, when I meet him."

"Don't blame you a bit," commented Mr. Berg. "Well, I must
be getting back."

He hastened out to his auto, while Tom and his father
watched the agent.

"Tom, never trust that man," advised the aged inventor
solemnly.

"Just what I was about to remark," said his son. "Well,
let's get back to work. Queer that he should come here
again, and it's queer about Andy Foger."

Father and son returned to the machine shop, while Mr.
Berg puffed away in his auto. A little later, Tom having
occasion to go to a building near the boundary line of the
cottage property which his father had hired for the season,
saw, through the hedge that bordered it, an automobile
standing in the road. A second glance showed him that it was
Mr. Berg's machine. Something had gone wrong with it, and
the agent had alighted to make an adjustment.

The young inventor was close to the man, though the latter
was unaware of his presence.

"Hang it all!" Tom heard Mr. Berg exclaim to himself. "I
wonder what they can be up to? They won't enter the
Government contests, and they won't say why. I believe
they're up to some game, and I've got to find out what it
is. I wonder if I couldn't use this Foger chap?"

"He seems to have it in for this Tom Swift," Mr. Berg went
on, still talking to himself, though not so low but that Tom
could hear him. "I think I'll try it. I'll get Andy Foger to
sneak around and find out what the game is. He'll do it, I
know."

By this time the auto was in working order again, and the
agent took his seat and started off.

"So that's how matters lie, eh?" thought Tom. "Well, Mr.
Berg, we'll be doubly on the lookout for you after this. As
for Andy Foger, I think I'll make him wish he'd never locked
me in that tank. So you expect to find out our 'game,' eh,
Mr. Berg? Well, when you do know it, I think it will
astonish you. I only hope you don't learn what it is until
we get at that sunken treasure, though."

But alas for Tom's hopes. Mr. Berg did learn of the object
of the treasure-seekers, and sought to defeat them, as we
shall learn as our story proceeds.




Chapter Six

Turning the Tables


When the young inventor informed his father what he had
overheard Mr. Berg saying, the aged inventor was not as much
worried as his son anticipated.

"All we'll have to do, Tom," he said, "is to keep quiet
about where we are going. Once we have the Advance afloat,
and try her out, we can start on our voyage for the South
American Coast and search for the sunken treasure. When we
begin our voyage under water I defy any one to tell where we
are going, or what our plans are. No, I don't believe we
need worry about Mr. Berg, though he probably means
mischief."

"Well, I'm going to keep my eyes open for him and Andy
Foger," declared Tom.

The days that followed were filled with work. Not only
were there many unexpected things to do about the submarine,
but Mr. Sharp was kept busy making inquiries about the
sunken treasure ship. These inquiries had to he made
carefully, as the adventurers did not want their plans
talked of, and nothing circulates more quickly than rumors
of an expedition after treasure of any kind.

"What about the old sea captain you were going to get to
go with us?" asked Mr. Swift of the balloonist one afternoon.
"Have you succeeded in finding one yet?"

"Yes; I am in communication with a man think will be just
the person for us. His name is Captain Alden Weston, and he
has sailed all over the world. He has also taken part in
more than one revolution, and, in fact, is a soldier of
fortune. I do not know him personally, but a friend of mine
knows him, and says he will serve us faithfully. I have
written to him, and he will he here in a few days."

"That's good. Now about the location of the wreck itself.
Have you been able to learn any more details?"

"Well, not many. You see, the Boldero was abandoned in a
storm, and the captain did not take very careful
observations. As nearly as it can be figured out the
treasure ship went to the bottom in latitude forty-five
degrees south, and longitude twenty-seven east from
Washington. That's a pretty indefinite location, but I hope,
once we get off the Uruguay coast, we can better it. We can
anchor or lay outside the harbor, and in the small boat we
carry go ashore and possibly gain more details. For it was
at Montevideo that the shipwrecked passengers and sailors
landed."

"Does Captain Weston know our object?" inquired Tom.

"No, and I don't propose to tell him until we are ready to
start," replied Mr. Sharp. "I don't know just how he'll
consider a submarine trip after treasure, but if I spring it
on him suddenly he's less likely to back out. Oh, I think
he'll go."

Somewhat unexpectedly the next day it was discovered that
certain tools and appliances were needed for the submarine,
and they had been left in the house at Shopton, where
Eradicate Sampson was in charge as caretaker during the
absence of Mr. Swift and his son and the housekeeper.

"Well, I suppose we'll have to go back after them,"
remarked Tom. "We'll take the airship, dad, and make a two-
days' trip of it. Is there anything else you want?"

"Well, you might bring a bundle of papers you'll find in
the lower right hand drawer of my desk. They contain some
memoranda I need."

Tom and Mr. Sharp had become so used to traveling in the
airship that it seemed no novelty to them, though they
attracted much attention wherever they went. They soon had
the Red Cloud in readiness for a flight, and rising in the
air above the shop that contained the powerful submarine, a
craft utterly different in type from the aeroplane, the nose
of the airship was pointed toward Shopton.

They made a good flight and landed near the big shed where
the bird of the air was kept. It was early evening when they
got to the Swift homestead, and Eradicate Sampson was glad
to see them.

Eradicate was a good cook, and soon had a meal ready for
the travelers. Then, while Mr. Sharp selected the tools and
other things needed, and put them in the airship ready for
the start back the next morning, Tom concluded he would take
a stroll into Shopton, to see if he could see his friend,
Ned Newton. It was early evening, and the close of a
beautiful day, a sharp shower in the morning having cooled
the air.

Tom was greeted by a number of acquaintances as he
strolled along, for, since the episode of the bank robbery,
when he had so unexpectedly returned with the thieves and
the cash, the lad was better known than ever.

"I guess Ned must be home" thought our hero as he looked
in vain for his chum among the throng on the streets. "I've
got time to take a stroll down to his house."

Tom was about to cross the street when he was startled by
the sound of an automobile horn loudly blown just at his
side. Then a voice called:

"Hey, there! Git out of the way if you don't want to be
run over!"

He looked up, and saw a car careening along. At the wheel
was the red-haired bully, Andy Foger, and in the tonneau
were Sam Snedecker and Pete Bailey.

"Git out of the way," added Sam, and he grinned
maliciously at Tom.

The latter stepped back, well out of the path of the car,
which was not moving very fast. Just in front of Tom was a
puddle of muddy water. There was no necessity for Andy
steering into it, but he saw his opportunity, and a moment
later one of the big pneumatic tires had plunged into the
dirty fluid, spattering it all over Tom, some even going as
high as his face.

"Ha! ha!" laughed Andy. "Maybe you'll get out of my way
next time, Tom Swift."

The young inventor was almost speechless from righteous
anger. He wiped the mud from his face, glanced down at his
clothes, which were all but ruined, and called out:

"Hold on there, Andy Foger! I want to see you!" for he
thought of the time when Andy had shut him in the tank.

"Ta! ta!" shouted Pete Bailey.

"See you later," added Sam.

"Better go home and take a bath, and then sail away in
your submarine," went on Andy. "I'll bet it will sink."

Before Tom could reply the auto had turned a corner.
Disgusted and angry, he tried to sop up some of the muddy
water with his handkerchief. While thus engaged he heard his
name called, and looked up to see Ned Newton.

"What's the matter? Fall down?" asked his chum.

"Andy Foger," replied Tom.

"That's enough," retorted Ned. "I can guess the rest.
We'll have to tar and feather him some day, and ride him out
of town on a rail. I'd kick him myself, only his father is a
director in the bank where I work, and I'd be fired if I
did. Can't afford any such pleasure. But some day I'll give
Andy a good trouncing, and then resign before they can
discharge me. But I'll be looking for another job before I
do that. Come on to my house, Tom, and I'll help you clean
up."

Tom was a little more presentable when he left his chum's
residence, after spending the evening there, but he was
still burning for revenge against Andy and his cronies. He
had half a notion to go to Andy's house and tell Mr. Foger
how nearly serious the bully's prank at the sub marine had
been, but be concluded that Mr. Foger could only uphold his
son. "No, I'll settle with him myself," decided Tom.

Bidding Eradicate keep a watchful eye about the house, and
leaving word for Mr. Damon to be sure to come to the coast
if he again called at the Shopton house, Tom and Mr. Sharp
prepared to make their return trip early the next morning.

The gas tank was filled and the Red Cloud arose in the
air. Then, with the propellers moving at moderate speed, the
nose of the craft was pointed toward the New Jersey coast.

A few miles out from Shopton, finding there was a contrary
wind in the upper regions where they were traveling, Mr.
Sharp descended several hundred feet. They were moving over
a sparsely settled part of the country, and looking down,
Tom saw, speeding along a highway, an automobile.

"I wonder who's in it?" he remarked, taking down a
telescope and peering over the window ledge of the cabin.
The next moment he uttered a startled exclamation.

"Andy  Foger, Sam  Snedecker and Pete Bailey!" he cried.
"Oh, I wish I had a bucket of water to empty on them."

"I know a better way to get even with them than that,"
said Mr. Sharp.

"How?" asked Tom eagerly.

"I'll show you," replied the balloonist. "It's a trick I
once played on a fellow who did me an injury. Here, you
steer for a minute until I get the thing fixed, then I'll
take charge."

Mr. Sharp went to the storeroom and came back with a long,
stout rope and a small anchor of four prongs. It was carried
to be used in emergencies, but so far had never been called
into requisition. Fastening the grapple to the cable, the
balloonist said:

"Now, Tom, they haven't seen you. You stand in the stern
and pay out the rope. I'll steer the airship, and what I
want you to do is to catch the anchor in the rear of their
car. Then I'll show you some fun."

Tom followed instructions. Slowly he lowered the rope with
the dangling grapple. The airship was also sent down, as the
cable was not quite long enough to reach the earth from the
height at which they were. The engine was run at slow speed,
so that the noise would not attract the attention of the
three cronies who were speeding along, all unconscious of
the craft in the air over their heads. The Red Cloud was
moving in the same direction as was the automobile.

The anchor was now close to the rear of Andy's car.
Suddenly it caught on the tonneau and Tom called that fact
to Mr. Sharp.

"Fasten the rope at the cleat," directed the balloonist.

Tom did so, and a moment later the aeronaut sent the
airship up by turning more gas into the container. At the
same time he reversed the engine and the Red Cloud began
pulling the touring car backward, also lifting the rear
wheels clear from the earth.

A startled cry from the occupants of the machine told Tom
and his friend that Andy and his cronies were aware
something was wrong. A moment later Andy, looking up, saw
the airship hovering in the air above him. Then he saw the
rope fast to his auto. The airship was not rising now, or
the auto would have been turned over, but it was slowly
pulling it backward, in spite of the fact that the motor of
the car was still going.

"Here! You let go of me!" cried Andy. "I'll have you
arrested if you damage my car."

"Come up here and cut the rope." called Tom leaning over
and looking down. He could enjoy the bully's discomfiture.
As for Sam and Pete, they were much frightened, and cowered
down on the floor of the tonneau.

"Maybe you'll shut me in the tank again and splash mud on
me!" shouted Tom.

The rear wheels of the auto were lifted still higher from
the ground, as Mr. Sharp turned on a little more gas. Andy
was not proof against this.

"Oh! oh!" he cried. "Please let me down, Tom. I'm awful
sorry for what I did! I'll never do it again! Please, please
let me down! Don't You'll tip me over!"

He had shut off his motor now, and was frantically
clinging to the steering wheel.

"Do you admit that you're a sneak and a coward?" asked
Tom, "rubbing it in."

"Yes, yes!  Oh, please let me down!"

"Shall we?" asked Tom of Mr. Sharp.

"Yes," replied the balloonist. "We can afford to lose the
rope and anchor for the sake of turning the tables. Cut the
cable."

Tom saw what was intended. Using a little hatchet, he
severed the rope with a single blow. With a crash that could
be heard up in the air where the Red Cloud hovered, the rear
wheels of the auto dropped to the ground. Then came two loud
reports.

"Both tires busted!" commented Mr. Sharp dryly, and Tom,
looking down, saw the trio of lads ruefully contemplating
the collapsed rubber of the rear wheels. The tables had been
effectually turned on Andy Foger. His auto was disabled, and
the airship, with a graceful sweep, mounted higher and
higher, continuing on its way to the coast.




Chapter Seven

Mr. Damon Will Go


"Well, I guess they've had their lesson," remarked Tom, as
he took an observation through the telescope and saw Andy
and his cronies hard at work trying to repair the ruptured
tires. "That certainly was a corking good trick."

"Yes," admitted Mr. Sharp modestly. "I once did something
similar, only it was a horse and wagon instead of an auto.
But let's try for another speed record. The conditions are
just right."

They arrived at the coast much sooner than they had dared
to hope, the Red Cloud proving herself a veritable wonder.

The remainder of that day, and part of the next, was spent
in working on the submarine.

"We'll launch her day after to-morrow," declared Mr. Swift
enthusiastically. "Then to see whether my calculations are
right or wrong."

"It won't be your fault if it doesn't work," said his son.
"You certainly have done your best."

"And so have you and Mr. Sharp and the others, for that
matter. Well, I have no doubt but that everything will be
all right, Tom."

"There!" exclaimed Mr. Sharp the next morning, as he was
adjusting a certain gage. "I knew I'd forget something. That
special brand of lubricating oil. I meant to bring it from
Shopton, and I didn't."

"Maybe I can get it in Atlantis," suggested Tom, naming
the coast city nearest to them. "I'll take a walk over. It
isn't far."

"Will you? I'll be glad to have you," resumed the
balloonist. "A gallon will be all we'll need."

Tom was soon on his way. He had to walk, as the roads were
too poor to permit him to use the motor-cycle, and the
airship attracted too much attention to use on a short trip.
He was strolling along, when from the other side of a row of
sand dunes, that lined the uncertain road to Atlantis, he
heard some one speaking. At first the tones were not
distinct, but as the lad drew nearer to the voice he heard
an exclamation.

"Bless my gold-headed cane! I believe I'm lost. He said it
was out this way somewhere, bet I don't see anything of it.
If I had that Eradicate Sampson here now I'd--bless my
shoelaces I don't know what I would do to him."

"Mr. Damon! Mr. Damon!" cried Tom. "Is that you?"

"Me? Of course it's me! Who else would it be?" answered
the voice. "But who are you. Why, bless my liver! If it
isn't Tom Swift!" he cried. "Oh, but I'm glad to see you! I
was afraid I was shipwrecked! Bless my gaiters, how are you,
anyhow? How is your father? How is Mr. Sharp, and all the
rest of them?"

"Pretty well. And you?"

"Me? Oh, I'm all right; only a trifle nervous. I called at
your house in Shopton yesterday, and Eradicate told me, as
well as he could, where you were located. I had nothing to
do, so I thought I'd take a run down here. But what's this I
hear about you? Are you going on a voyage?"

"Yes."

"In the air? May I go along again? I certainly enjoyed my
other trip in the Red Cloud. What is, all but the fire and
being shot at. May I go?"

"We're going on a different sort of trip this time," said
the youth.

"Where?"

"Under water."

"Under water?  Bless my sponge bath! You don't mean it!"

"Yes. Dad has completed the submarine he was working on
when we were off in the airship, and it will be launched the
day after to-morrow."

"Oh, that's so. I'd forgotten about it. He's going to try
for the Government prize, isn't he? But tell me more about
it. Bless my scarf-pin, but I'm glad I met you! Going into
town, I take it. Well, I just came from there, but I'll walk
back with you. Do you think--is there any possibility --that
I could go with you? Of course, I don't want to crowd you,
but--"

"Oh, there'll be plenty of room," replied the young
inventor. "In fact, more room than we had in the airship. We
were talking only the other day about the possibility of you
going with us, but we didn't think you'd risk it."

"Risk it? Bless my liver! Of course I'll risk' it! It
can't be as bad as sailing in the air. You can't fall,
that's certain."

"No; but maybe you can't rise," remarked Tom grimly.

"Oh, we won't think of that. Of course, I'd like to go. I
fully expected to be killed in the Red Cloud, but as I
wasn't I'm ready to take a chance in the water. On the
whole, I think I prefer to be buried at sea, anyhow. Now,
then, will you take me?"

"I think I can safely promise," answered Tom with a smile
at his friend's enthusiasm.

The two were approaching the city, having walked along as
they talked. There were still some sand dunes near the road,
and they kept on the side of these, nearest the beach, where
they could watch the breakers.

"But you haven't told me where you are going," went on Mr.
Damon, after blessing a few dozen objects. "Where do the
Government trials take place?"

"Well," replied the lad, "to be frank with you, we have
abandoned our intention of trying for the Government prize."

"Not going to try for it? Bless my slippers! Why not?
Isn't fifty thousand dollars worth striving for? And, with
the kind of a submarine you say you have, you ought to be
able to win."

"Yes, probably we could win," admitted the young inventor,
"but we are going to try for a better prize."

"A better one? I don't understand."

"Sunken treasure," explained Tom. "There's a ship sunk off
the coast of Uruguay, with three hundred thousand dollars in
gold bullion aboard. Dad and I are going to try to recover
that in our submarine. We're going to start day after
to-morrow, and, if you like, you may go along."

"Go along! Of course I'll go along!" cried the eccentric
man. "But I never heard of such a thing. Sunken treasure!
Three hundred thousand dollars in gold! My, what a lot of
money! And to go after it in a submarine! It's as good as a
story!"

"Yes, we hope to recover all the treasure," said the lad.
"We ought to be able to claim at least half of it."

"Bless my pocketbook!" cried Mr. Damon, but Tom did not
hear him. At that instant his attention was attracted by
seeing two men emerge from behind the sand dune near which
he and Mr. Damon had halted momentarily, when the youth
explained about the treasure. The man looked sharply at Tom.
A moment later the first man was joined by another, and at
the sight of him our hero could not repress an exclamation
of alarm. For the second man was none other than Addison
Berg.

The latter glanced quickly at Tom, and then, with a hasty
word to his companion, the two swung around and made off in
the opposite direction to that in which they had been
walking.

"What's the matter?" asked Mr. Damon, seeing the young
inventor was strangely affected.

"That--that man," stammered the lad.

"You don't mean to tell me that was one the Happy Harry
gang, do you?"

"No. But one, or both of those men, may prove to be worse.
That second man was Addison Berg, and he's agent for a firm
of submarine boat builders who are rivals of dad's. Berg has
been trying to find out why we abandoned our intention of
competing for the Government prize."

"I hope you didn't tell him."

"I didn't intend to," replied Tom, smiling grimly, "but
I'm afraid I have, however He certainly overheard what I
said. I spoke too loud. Yes, he must have heard me. That's
why he hurried off so."

"Possibly no harm is done. You didn't give the location of
the sunken ship."

"No; but I guess from what I said it will be easy enough
to find. Well, if we're going to have a fight for the
possession of that sunken gold, I'm ready for it. The
Advance is well equipped for a battle. I must tell dad of
this. It's my fault."

"And partly mine, for asking you such leading questions in
a public place," declared Mr. Damon. "Bless my coat-tails,
but I'm sorry! Maybe, after all, those men were so
interested in what they themselves were saying that they
didn't understand what you said."

But if there had been any doubts on this score they would
have been dissolved had Tom and his friend been able to see
the actions of Mr. Berg and his companion a little later.
The plans of the treasure-hunters had been revealed to their
ears.




Chapter Eight

Another Treasure Expedition


While Tom and Mr. Damon continued on to Atlantis after the
oil, the young inventor lamenting from time to time that his
remarks about the real destination of the Advance had been
overheard by Mr. Berg, the latter and his companion were
hastening back along the path that ran on one side of the
sand dunes.

"What's your hurry?" asked Mr. Maxwell, who was with the
submarine agent. "You turned around as if you were shot when
you saw that man and the lad. There didn't appear to be any
cause for such a hurry. From what I could hear they were
talking about a submarine. You're in the same business. You
might be friends."

"Yes, we might," admitted Mr. Berg with a peculiar smile;
"but, unless I'm very much mistaken, we're going to be
rivals."

"Rivals? What do you mean?"

"I can't tell you now. Perhaps I may later. But if you
don't mind, walk a little faster, please. I want to get to a
long-distance telephone."

"What for?"

"I have just overheard something that I wish to
communicate to my employers, Bentley & Eagert."

"Overheard something? I don't see what it could be, unless
that lad--"

"You'll learn in good time," went on the submarine agent.
"But I must telephone at once."

A little later the two men had reached a trolley line that
ran into Atlantis, and they arrived at the city before Mr.
Damon and Tom got there, as the latter had to go by a
circuitous route. Mr. Berg lost no time in calling up his
firm by telephone.

"I have had another talk with Mr. Swift," he reported to
Mr. Bentley, who came to the instrument in Philadelphia.

"Well, what does he say?" was the impatient question. "I
can't understand his not wanting to try for the Government
prize. It is astonishing. You said you were going to
discover the reason, Mn Berg, but you haven't done so."

"I have."

"What is it?"

"Well, the reason Mr. Swift and his son don't care to try
for the fifty thousand dollar prize is that they are after
one of three hundred thousand dollars."

"Three hundred thousand dollars!" cried Mr, Bentley. "What
government is going to offer such a prize as that for
submarines, when they are getting almost as common as
airships? We ought to have a try for that ourselves. What
government is it?"

"No government at all. But I think we ought to have a try
for it, Mr. Bentley."

"Explain."

"Well, I have just learned, most accidentally, that the
Swifts are going after sunken treasure--three hundred
thousand dollars in gold bullion."

"Sunken treasure? Where?

"I don't know exactly, but off the coast of Uruguay," and
Mr. Berg rapidly related what he had overheard Tom tell Mr.
Damon. Mr. Bentley was much excited and impatient for more
details, but his agent could not give them to him.

"Well," concluded the senior member of the firm of
submarine boat builders, "if the Swifts are going after
treasure, so can we. Come to Philadelphia at once, Mr. Berg,
and we'll talk this matter over. There is no time to lose.
We can afford to forego the Government prize for the chance
of getting a much larger one. We have as much right to
search for the sunken gold as the Swifts have. Come here at
once, and we will make our plans."

"All right," agreed the agent with a smile as he hung up
the receiver. "I guess," he murmured to himself, "that you
won't be so high and mighty with me after this, Tom Swift.
We'll see who has the best boat, after all. We'll have a
contest and a competition, but not for a government prize.
It will be for the sunken gold."

It was easy to see that Mr. Berg was much pleased with
himself.

Meanwhile, Tom and Mr. Damon had reached Atlantis, and had
purchased the oil. They started back, but Tom took a street
leading toward the center of the place, instead of striking
for the beach path, along which they had come.

"Where are you going?" asked Mr. Damon.

"I want to see if that Andy Foger has come back here,"
replied the lad, and he told of having been shut in the tank
by the bully.

"I've never properly punished him for that trick," he went
on, "though we did manage to burst his auto tires. I'm
curious to know how he knew enough to turn that gear and
shut the tank door. He must have been loitering near the
shop, seen me go in the submarine alone, watched his chance
and sneaked in after me. But I'd like to get a complete
explanation, and if I once got hold of Andy I could make him
talk," and Tom clenched his fist in a manner that augured no
good for the squint-eyed lad. "He was stopping at the same
hotel with Mr. Berg, and be hurried away after the trick he
played on me. I next saw him in Shopton, but I thought
perhaps he might have come back here. I'm going to inquire
at the hotel," he added.

Andy's name was not on the register since his hasty
flight, however, and Tom, after inquiring from the clerk and
learning that Mr. Berg was still a guest at the hostelry,
rejoined Mr. Damon.

"Bless my hat!" exclaimed that eccentric individual as
they started back to the lonely beach where the submarine
was awaiting her advent into the water. "The more I think
of the trip I'm going to take, the more I like it."

"I hope you will," remarked Tom. "It will be a new
experience for all of us. There's only one thing worrying
me, and that is about Mr. Berg having overheard what I
said."

"Oh, don't worry about that. Can't we slip away and leave
no trace in the water?"

"I hope so, but I must tell dad and Mr. Sharp about what
happened."

The aged inventor was not a little alarmed at what his son
related, but he agreed with Mr. Damon, whom he heartily
welcomed, that little was to be apprehended from Berg and
his employers.

"They know we're after a sunken wreck, but that's all they
do know," said Tom's father. "We are only waiting for the
arrival of Captain Alden Weston, and then we will go. Even
if Bentley & Eagert make a try for the treasure we'll have
the start of them, and this will be a case of first come,
first served. Don't worry, Tom. I'm glad you're going, Mn
Damon. Come, I will show you our submarine."

As father and son, with their guest, were going to the
machine shop, Mr. Sharp met them. He had a letter in his
hand.

"Good news!" the balloonist cried. "Captain Weston will be
with us to-morrow. He will arrive at the Beach Hotel in
Atlantis, and wants one of us to meet him there. He has
considerable information about the wreck."

"The Beach Hotel," murmured Tom. "That is where Mr. Berg
is stopping. I hope he doesn't worm any of our secret from
Captain Weston," and it was with a feeling of uneasiness
that the young inventor continued after his father and Mr.
Damon to where the submarine was.




Chapter Nine

Captain Weston's Advent


"Bless my water ballast, but that certainly is a fine boat!"
cried Mr. Damon, when he had been shown over the new craft.
"I think I shall feel even safer in that than in the Red Cloud."

"Oh, don't go back on the airship!" exclaimed Mn Sharp. "I
was counting on taking you on another trip."

"Well, maybe after we get back from under the ocean,"
agreed Mr. Damon. "I particularly like the cabin
arrangements of the Advance. I think I shall enjoy myself."

He would be hard to please who could not take pleasure
from a trip in the submarine. The cabin was particularly
fine, and the sleeping arrangements were good.

More supplies could be carried than was possible on the
airship, and there was more room in which to cook and serve
food. Mr. Damon was fond of good living, and the kitchen
pleased him as much as anything else.

Early the next morning Tom set out for Atlantis, to meet
Captain Weston at the hotel. The young inventor inquired of
the clerk whether the seafaring man had arrived, and was
told that he had come the previous evening.

"Is he in his room?" asked Tom.

"No," answered the clerk with a peculiar grin. "He's an
odd character. Wouldn't go to bed last night until we had
every window in his room open, though it was blowing quite
hard, and likely to storm. The captain said he was used to
plenty of fresh air. Well, I guess he got it, all right."

"Where is he now?" asked the youth, wondering what sort of
an individual he was to meet.

"Oh, he was up before sunrise, so some of the scrubwomen
told me. They met him coming from his room, and he went
right down to the beach with a big telescope he always
carries with him. He hasn't come back yet. Probably he's
down on the sand."

"Hasn't he had breakfast?"

"No. He left word he didn't want to eat until about four
bells, whatever time that is."

"It's ten o'clock," replied Tom, who had been studying up
on sea terms lately. "Eight bells is eight o'clock in the
morning, or four in the afternoon or eight at night,
according to the time of day. Then there's one bell for
every half hour, so four bells this morning would be ten
o'clock in this watch, I suppose."

"Oh, that's the way it goes, eh?" asked the clerk. "I
never could get it through my head. What is twelve o'clock
noon?"

"That's eight bells, too; so is twelve o'clock midnight.
Eight bells is as high as they go on a ship. But I guess
I'll go down and see if I can meet the captain. It will soon
be ten o'clock, or four bells, and he must be hungry for
breakfast. By the way, is that Mr. Berg still here?"

"No; he went away early this morning. He and Captain
Weston seemed to strike up quite an acquaintance, the night
clerk told me. They sat and smoked together until long after
midnight, or eight bells," and the clerk smiled as he
glanced down at the big diamond ring on his little finger.

"They did?" fairly exploded Tom, for he had visions of
what the wily Mr. Berg might worm out of the simple captain.

"Yes. Why, isn't the captain a proper man to make friends
with?" and the clerk looked at Tom curiously.

"Oh, yes, of course," was the hasty answer. "I guess I'll
go and see if I can find him--the captain, I mean."

Tom hardly knew what to think. He wished his father, or
Mr. Sharp, had thought to warn Captain Weston against
talking of the wreck. It might be too late now.

The young inventor hurried to the beach, which was not far
from the hotel. He saw a solitary figure pacing up and down,
and from the fact that the man stopped, every now and then,
and gazed seaward through a large telescope, the lad
concluded it was the captain for whom he was in search. He
approached, his footsteps making no sound on the sand. The
man was still gazing through the glass.

"Captain Weston?" spoke Tom.

Without a show of haste, though the voice must have
startled him, the captain turned. Slowly he lowered the
telescope, and then he replied softly:

"That's my name. Who are you, if I may ask?"

Tom was struck, more than by anything else, by the gentle
voice of the seaman. He had prepared himself, from the
description of Mr. Sharp, to meet a gruff, bewhiskered
individual, with a voice like a crosscut saw, and a rolling
gait. Instead he saw a man of medium size, with a smooth
face, merry blue eyes, and the softest voice and gentlest
manner imaginable. Tom was very much disappointed. He had
looked for a regular sea-dog, and he met a landsman, as he
said afterward. But it was not long before our hero changed
his mind regarding Captain Weston.

"I'm Tom Swift," the owner of that name said, "and I have
been sent to show you the way to where our ship is ready to
launch." The young inventor refrained from mentioning
submarine, as it was the wish of Mn Sharp to disclose this
feature of the voyage to the sailor himself.

"Ha, I thought as much," resumed the captain quietly.
"It's a fine day, if I may be permitted to say so," and he
seemed to hesitate, as if there was some doubt whether or
not he might make that observation.

"It certainly is," agreed the lad. Then, with a smile he
added: "It is nearly eight bells."

"Ha!" exclaimed the captain, also smiling, but even his
manner of saying "Ha!" was less demonstrative than that of
most persons. "I believe I am getting hungry, if I may be
allowed the remark," and again he seemed asking Tom's pardon
for mentioning the fact.

"Perhaps you will come back to the cabin and have a little
breakfast with me," he went on. "I don't know what sort of a
galley or cook they have aboard the Beach Hotel, but it
can't be much worse than some I've tackled."

"No, thank you," answered the youth. "I've had my
breakfast. But I'll wait for you, and then I'd like to get
back. Dad and Mr. Sharp are anxious to meet you."

"And I am anxious to meet them, if you don't mind me
mentioning it," was the reply, as the captain once more put
the spyglass to his eye and took an observation. "Not many
sails in sight this morning," he added. "But the weather is
fine, and we ought to get off in good shape to hunt for the
treasure about which Mr. Sharp wrote me. I believe we are
going after treasure, he said; "that is, if you don't mind
talking about it."

"Not in the least," replied Tom quickly, thinking this a
good opportunity for broaching a subject that was worrying
him. "Did you meet a Mr. Berg here last night, Captain
Weston?" he went on.

"Yes. Mr. Berg and I had quite a talk. He is a well-
informed man."

"Did he mention the sunken treasure?" asked the lad, eager
to find out if his suspicions were true.

"Yes, he did, if you'll excuse me putting it so plainly,"
answered the seaman, as if Tom might be offended at so
direct a reply. But the young inventor was soon to learn
that this was only an odd habit with the seaman.

"Did he want to know where the wreck of the Boldero was
located?" continued the lad. "That is, did he try to
discover if you knew anything about it?"

"Yes," said Mr. Weston, "he did. He pumped me, if you are
acquainted with that term, and are not offended by it. You
see, when I arrived here I made inquiries as to where your
father's place was located. Mr. Berg overheard me, and
introduced himself as agent for a shipbuilding concern. He
was very friendly, and when he said he knew you and your
parent, I thought he was all right."

Tom's heart sank. His worst fears were to be realized, he
thought.

"Yes, he and I talked considerable, if I may be permitted
to say so," went on the captain. "He seemed to know about
the wreck of the Boldero, and that she had three hundred
thousand dollars in gold aboard. The only thing he didn't
know was where the wreck was located. He knew it was off
Uruguay somewhere, but just where he couldn't say. So he
asked me if I knew, since he must have concluded that I was
going with you on the gold-hunting expedition."

"And you do know, don't you?" asked Tom eagerly.

"Well, I have it pretty accurately charted out, if you
will allow me that expression," was the calm answer. "I took
pains to look it up at the request of Mr. Sharp."

"And he wanted to worm that information out of you?"
inquired the youth excitedly.

"Yes, I'm afraid he did."

"Did you give him the location?"

"Well," remarked the captain, as he took another
observation before closing up the telescope, "you see, while
we were talking, I happened to drop a copy of a map I'd
made, showing the location of the wreck. Mr. Berg picked it
up to hand to me, and he looked at it."

"Oh!" cried Tom. "Then he knows just where the treasure
is, and he may get to it ahead of us. It's too bad."

"Yes," continued the seaman calmly, "Mr. Berg picked up
that map, and he looked very closely at the latitude and
longitude I had marked as the location of the wreck."

"Then he won't have any trouble finding it," murmured our
hero.

"Eh? What's that?" asked the captain, "if I may be
permitted to request you to repeat what you said."

"I say he won't have any trouble locating the sunken
Boldero," repeated Tom.

"Oh, but I think he will, if he depends on that map," was
the unexpected reply. "You see," explained Mr. Weston, "I'm
not so simple as I look. I sensed what Mr. Berg was after,
the minute he began to talk to me. So I fixed up a little
game on him. The map which I dropped on purpose, not
accidentally, where he would see it, did have the location
of the wreck marked. Only it didn't happen to be the right
location. It was about five hundred miles out of the way,
and I rather guess if Mr. Berg and his friends go there for
treasure they'll find considerable depth of water and quite
a lonesome spot. Oh, no, I'm not as easy as I look, if you
don't mind me mentioning that fact; and when a scoundrel
sets out to get the best of me, I generally try to turn the
tables on him. I've seen such men as Mr. Berg before. I'm
afraid, I'm very much afraid, the sight he had of the fake
map I made won't do him much good. Well, I declare, it's
past four bells. Let's go to breakfast, if you don't mind me
asking you," and with that the captain started off up the
beach, Tom following, his ideas all a whirl at the unlooked-
for outcome of the interview.




Chapter Ten

Trial of the Submarine


Tom felt such a relief at hearing of Captain Weston's ruse
that his appetite, sharpened by an early breakfast and the
sea air, came to him with a rush, and he had a second
morning meal with the odd sea captain, who chuckled heartily
when he thought of how Mn Berg had been deceived.

"Yes," resumed Captain Weston, over his bacon and eggs, "I
sized him up for a slick article as soon as I laid eyes on
him. But he evidently misjudged me, if I may be permitted
that term. Oh, well, we may meet again, after we secure the
treasure, and then I can show him the real map of the
location of the wreck."

"Then you have it?" inquired the lad eagerly.

Captain Weston nodded, before hiding his face behind a
large cup of coffee; his third, by the way.

"Let me see it?" asked Tom quickly. The captain set down
his cup. He looked carefully about the hotel dining-room.
There were several guests, who, like himself, were having a
late breakfast.

"It's a good plan," the sailor said slowly, "when you're
going into unknown waters, and don't want to leave a wake
for the other fellow to follow, to keep your charts locked
up. If it's all the same to you," he added diffidently, "I'd
rather wait until we get to where your father and Mr. Sharp
are before displaying the real map. I've no objection to
showing you the one Mr. Berg saw," and again he chuckled.

The young inventor blushed at his indiscretion. He felt
that the news of the search for the treasure had leaked out
through him, though he was the one to get on the trail of it
by seeing the article in the paper. Now he had nearly been
guilty of another break. He realized that he must be more
cautious. The captain saw his confusion, and said:

"I know how it is. You're eager to get under way. I don't
blame you. I was the same myself when I was your age. But
we'll soon be at your place, and then I'll tell you all I
know. Sufficient now, to say that I believe I have located
the wreck within a few miles. I got on the track of a sailor
who had met one of the shipwrecked crew of the Boldero, and
he gave me valuable information. Now tell me about the
craft we are going in. A good deal depends on that."

Tom hardly knew what to answer. He recalled what Mr. Sharp
had said about not wanting to tell Captain Weston, until
the last moment, that they were going in a submarine, for
fear the old seaman (for he was old in point of service
though not in years) might not care to risk an under-water
trip. Therefore Tom hesitated. Seeing it, Captain Weston
remarked quietly:

"I mean, what type is your submarine? Does it go by
compressed air, or water power?"

"How do you know it's a submarine?" asked the young
inventor quickly, and in some confusion.

"Easy enough. When Mr. Berg thought he was pumping me, I
was getting a lot of information from him. He told me about
the submarine his firm was building, and, naturally, he
mentioned yours. One thing led to another until I got a
pretty good idea of your craft. What do you call it?"

"The Advance."

"Good name. I like it, if you don't mind speaking of it."

"We were afraid you wouldn't like it," commented Tom.

"What, the name?,'

"No, the idea of going in a submarine."

"Oh," and Captain Weston laughed. "Well, it takes more
than that to frighten me, if you'll excuse the expression.
I've always had a hankering to go under the surface, after
so many years spent on top. Once or twice I came near going
under, whether I wanted to or not, in wrecks, but I think I
prefer your way. Now, if you're all done, and don't mind me
speaking of it, I think we'll start for your place. We must
hustle, for Berg may yet get on our trail, even if he has
got the wrong route," and he laughed again.

It was no small relief to Mn Swift and Mr. Sharp to learn
that Captain Weston had no objections to a submarine, as
they feared he might have. The captain, in his diffident
manner, made friends at once with the treasure-hunters, and
he and Mr. Damon struck up quite an acquaintance. Tom told
of his meeting with the seaman, and the latter related, with
much gusto, the story of how he had fooled Mr. Berg.

"Well, perhaps you'd like to come and take a look at the
craft that is to be our home while we're beneath the water,"
suggested Mr. Swift and the sailor assenting, the aged
inventor, with much pride, assisted by Tom, pointed out on
the Advance the features of interest. Captain Weston gave
hearty approval, making one or two minor suggestions, which
were carried out.

"And so you launch her to-morrow," he concluded, when he
had completed the inspection "Well, I hope it's a success,
if I may be permitted to say so."

There were busy times around the machine shop next day. So
much secrecy had been maintained that none of the residents,
or visitors to the coast resort, were aware that in their
midst was such a wonderful craft as the submarine. The last
touches were put on the under-water ship; the ways, leading
from the shop to the creek, were well greased, and all was
in readiness for the launching. The tide would soon be at
flood, and then the boat would slide down the timbers (at
least, that was the hope of all), and would float in the
element meant to receive her. It was decided that no one
should be aboard when the launching took place, as there was
an element of risk attached, since it was not known just how
buoyant the craft was. It was expected she would float,
until the filled tanks took her to the bottom, but there was
no telling.

"It will be flood tide now in ten minutes," remarked
Captain Weston quietly, looking at his watch. Then he took
an observation through the telescope. "No hostile ships
hanging in the offing," he reported. "All is favorable, if
you don't mind me saying so," and he seemed afraid lest his
remark might give offense.

"Get ready," ordered Mr. Swift. "Tom, see that the ropes
are all clear," for it had been decided to ease the Advance
down into the water by means of strong cables and
windlasses, as the creek was so narrow that the submarine,
if launched in the usual way, would poke her nose into the
opposite mud bank and stick there.

"All clear," reported the young inventor.

"High tide!" exclaimed the captain a moment later,
snapping shut his watch.

"Let go!" ordered Mr. Swift, and the various windlasses
manned by the inventor, Tom and the others began to unwind
their ropes. Slowly the ship slid along the greased ways.
Slowly she approached the water. How anxiously they all
watched her! Nearer and nearer her blunt nose, with the
electric propulsion plate and the auxiliary propeller, came
to the creek, the waters of which were quiet now, awaiting
the turn of the tide.

Now little waves lapped the steel sides. It was the first
contact of the Advance with her native element.

"Pay out the rope faster!" cried Mr. Swift.

The windlasses were turned more quickly Foot by foot the
craft slid along until, with a final rush, the stern left
the ways and the submarine was afloat. Now would come the
test. Would she ride on an even keel, or sink out of sight,
or turn turtle? They all ran to the water's edge, Tom in the
lead.

"Hurrah!" suddenly yelled the lad, trying to stand on his
head. "She floats! She's a success! Come on! Let's get
aboard!"

For, true enough, the Advance was riding like a duck on
the water. She had been proportioned just right, and her
lines were perfect. She rode as majestically as did any ship
destined to sail on the surface, and not intended to do
double duty.

"Come on, we must moor her to the pier," directed Mr.
Sharp. "The tide will turn in a few minutes and take her out
to sea."

He and Tom entered a small boat, and soon the submarine
was tied to a small dock that had been built for the
purpose.

"Now to try the engine," suggested Mr. Swift, who was
almost trembling with eagerness; for the completion of the
ship meant much to him.

"One moment," begged Captain Weston. "If you don't mind,
I'll take an observation," he went on, and he swept the
horizon with his telescope. "All clear," he reported. "I
think we may go aboard and make a trial trip."

Little time was lost in entering the cabin and engine-
room, Garret Jackson accompanying the party to aid with the
machinery. It did not take long to start the motors, dynamos
and the big gasolene engine that was the vital part of the
craft. A little water was admitted to the tanks for ballast,
since the food and other supplies were not yet on board. The
Advance now floated with the deck aft of the conning tower
showing about two feet above the surface of the creek. Mr.
Swift and Tom entered the pilot house.

"Start the engines," ordered the aged inventor, "and we'll
try my new system of positive and negative electrical
propulsion."

There was a hum and whir in the body of the ship beneath
the feet of Tom and his father. Captain Weston stood on the
little deck near the conning tower.

"All ready?" asked the youth through the
speaking tube to Mr. Sharp and Mr. Jackson in
the engine-room.

"All ready," came the answer.

Tom threw over the connecting lever, while his father
grasped the steering wheel. The Advance shot forward, moving
swiftly along, about half submerged.

"She goes! She goes!" cried Tom

"She certainly does, if I may be permitted to say so," was
the calm contribution of Captain Weston. "I congratulate
you."

Faster and faster went the new craft. Mr. Swift headed her
toward the open sea, but stopped just before passing out of
the creek, as he was not yet ready to venture into deep
water.

"I want to test the auxiliary propellers," he said. After
a little longer trial of the electric propulsion plates,
which were found to work satisfactorily, sending the
submarine up and down the creek at a fast rate, the screws,
such as are used on most submarines, were put into gear.
They did well, but were not equal to the plates, nor was so
much expected of them.

"I am perfectly satisfied," announced Mr. Swift as he once
more headed the boat to sea. "I think, Captain Weston, you
had better go below now."

"Why so?"

"Because I am going to completely submerge the craft. Tom,
close the conning tower door. Perhaps you will come in here
with us, Captain Weston, though it will be rather a tight
fit."

"Thank you, I will. I want to see how it feels to be in a
pilot house under water."

Tom closed the water-tight door of the conning tower. Word
was sent through the tube to the engine-room that a more
severe test of the ship was about to be made. The craft was
now outside the line of breakers and in the open sea.

"Is everything ready, Tom?" asked his father in a quiet
voice.

"Everything," replied the lad nervously, for the
anticipation of being about to sink below the surface was
telling on them all, even on the calm, old sea captain.

"Then open the tanks and admit the water," ordered Mr.
Swift.

His son turned a valve and adjusted some levers. There was
a hissing sound, and the Advance began sinking. She was
about to dive beneath the surface of the ocean, and those
aboard her were destined to go through a terrible experience
before she rose again.




Chapter Eleven

On the Ocean Bed


Lower and lower sank the submarine. There was a swirling
and foaming of the water as she went down, caused by the air
bubbles which the craft carried with her in her descent.
Only the top of the conning tower was out of water now, the
ocean having closed over the deck and the rounded back of
the boat. Had any one been watching they would have imagined
that an accident was taking place.

In the pilot house, with its thick glass windows, Tom, his
father and Captain Weston looked over the surface of the
ocean, which every minute was coming nearer and nearer to
them.

"We'll be all under in a few seconds," spoke Tom in a
solemn voice, as he listened to the water hissing into the
tanks.

"Yes, and then we can see what sort of progress we will
make," added Mr. Swift. "Everything is going fine, though,"
he went on cheerfully. "I believe I have a good boat."

"There is no doubt of it in my mind," remarked Captain
Weston, and Tom felt a little disappointed that the sailor
did not shout out some such expression as "Shiver my
timbers!" or "Keel-haul the main braces, there, you lubber!"
But Captain Weston was not that kind of a sailor, though his
usually quiet demeanor could be quickly dropped on
necessity, as Tom learned later.

A few minutes more and the waters closed over the top of
the conning tower. The Advance was completely submerged.
Through the thick glass windows of the pilot house the
occupants looked out into the greenish water that swirled
about them; but it could not enter. Then, as the boat went
lower, the light from above gradually died out, and the
semi-darkness gave place to gloom.

"Turn on the electrics and the searchlight, Tom," directed
his father.

There was the click of a switch, and the conning tower was
flooded with light. But as this had the effect of
preventing the three from peering out into the water, just
as one in a lighted room cannot look out into the night, Tom
shut them off and switched on the great searchlight. This
projected its powerful beams straight ahead and there, under
the ocean, was a pathway of illumination for the treasure-
seekers.

"Fine!" cried Captain Weston, with more enthusiasm than he
had yet manifested. "That's great, if you don't mind me
mentioning it. How deep are we?"

Tom glanced at a gage on the side of the pilot tower.

"Only about sixty feet," he answered.

"Then don't go any deeper!" cried the captain hastily. "I
know these waters around here, and that's about all the
depth you've got. You'll be on the bottom in a minute."

"I intend to get on the bottom after a while," said Mr.
Swift, "but not here. I want to try for a greater distance
under water before I come to rest on the ocean's bed. But I
think we are deep enough for a test. Tom, close the tank
intake pipes and we'll see how the Advance will progress
when fully submerged."

The hissing stopped, and then, wishing to see how the
motors and other machinery would work, the aged inventor and
his son, accompanied by Captain Weston, descended from the
conning tower, by means of an inner stairway, to the
interior of the ship. The submarine could be steered and
managed from below or above. She was now floating about
sixty-five feet below the surface of the bay.

"Well, how do you like it?" asked Tom of Mr. Damon, as he
saw his friend in an easy chair in the living-room or main
cabin of the craft, looking out of one of the plate-glass
windows on the side.

"Bless my spectacles, it's the most wonderful thing I ever
dreamed of!" cried the queer character, as he peered at the
mass of water before him. "To think that I'm away down under
the surface, and yet as dry as a bone. Bless my necktie, but
it's great! What are we going to do now?"

"Go forward," replied the young inventor.

"Perhaps I had better make an observation," suggested
Captain Weston, taking his telescope from under his arm,
where he had carried it since entering the craft, and
opening it. "We may run afoul of something, if you don't
mind me mentioning such a disagreeable subject." Then, as he
thought of the impossibility of using his glass under water,
he closed it.

"I shall have little use for this here, I'm afraid," he
remarked with a smile. "Well, there's some consolation.
We're not likely to meet many ships in this part of the
ocean. Other vessels are fond enough of remaining on the
surface. I fancy we shall have the depths to ourselves,
unless we meet a Government submarine, and they are hardly
able to go as deep as we can. No, I guess we won't run into
anything and I can put this glass away."

"Unless we run into Berg and his crowd," suggested Tom in
a low voice.

"Ha! ha!" laughed Captain Weston, for he did not want Mr.
Swift to worry over the unscrupulous agent. "No, I don't
believe we'll meet them, Tom. I guess Berg is trying to work
out the longitude and latitude I gave him. I wish I could
see his face when he realizes that he's been deceived by
that fake map."

"Well, I hope he doesn't discover it too soon and trail
us," went on the lad. "But they're going to start the
machinery now. I suppose you and I had better take charge of
the steering of the craft. Dad will want to be in the
engine-room."

"All right," replied the captain, and he moved forward
with the lad to a small compartment, shut off from the
living-room, that served as a pilot house when the conning
tower was not used. The same levers, wheels and valves were
there as up above, and the submarine could be managed as
well from there as from the other place.

"Is everything all right?" asked Mn Swift as he went into
the engine-room, where Garret Jackson and Mr. Sharp were
busy with oil cans.

"Everything," replied the balloonist. "Are you going to
start now?"

"Yes, we're deep enough for a speed trial. We'll go out to
sea, however, and try for a lower depth record, as soon as
there's enough water. Start the engine."

A moment later the powerful electric currents were flowing
into the forward and aft plates, and the Advance began to
gather way, forging through the water.

"Straight ahead, out to sea, Tom," called his father to
him.

"Aye, aye, sir," responded the youth.

"Ha! Quite seaman-like, if you don't mind a reference to
it," commented Captain Weston with a smile. "Mind your helm,
boy, for you don't want to poke her nose into a mud bank, or
run up on a shoal."

"Suppose you steer?" suggested the lad. "I'd rather take
lessons for a while."

"All right. Perhaps it will be safer. I know these waters
from the top, though I can't say as much for the bottom.
However, I know where the shoals are."

The powerful searchlight was turned, so as to send its
beams along the path which the submarine was to follow, and
then, as she gathered speed, she shot ahead, gliding through
the waters like a fish.

Mr. Damon divided his time between the forward pilot-room,
the living-apartment, and the place where Mr. Swift, Garret
Jackson and Mr. Sharp were working over the engines. Every
few minutes he would bless some part of himself, his
clothing, or the ship. Finally the old man settled down to
look through the plate-glass windows in the main apartment.

On and on went the submarine. She behaved perfectly, and
was under excellent control. Some times Tom, at the request
of his father, would send her toward the surface by means of
the deflecting rudder. Then she would dive to the bottom
again. Once, as a test, she was sent obliquely to the
surface, her tower just emerging, and then she darted
downward again, like a porpoise that had come up to roll
over, and suddenly concluded to seek the depths. In fact,
had any one seen the maneuver they would have imagined the
craft was a big fish disporting itself.

Captain Weston remained at Tom's side, giving him
instructions, and watching the compass in order to direct
the steering so as to avoid collisions. For an hour or more
the craft was sent almost straight ahead at medium speed.
Then Mr. Swift, joining his son and the captain, remarked:

"How about depth of water here, Captain Weston?"

"You've got more than a mile."

"Good! Then I'm going down to the bottom of the sea! Tom,
fill the tanks still more.

"Aye, aye, sir," answered the lad gaily. "Now for a new
experience!"

"And use the deflecting rudder, also," advised his father.
"That will hasten matters."

Five minutes later there was a slight jar noticeable.

"Bless my soul! What's that?" cried Mr. Damon. "Have we
hit something?"

"Yes," answered Tom with a smile.

"What, for gracious sake?"

"The bottom of the sea. We're on the bed of the ocean."




Chapter Twelve

For a Breath of Air


They could hardly realize it, yet the depth-gage told the
story. It registered a distance below the surface of the
ocean of five thousand seven hundred feet--a little over a
mile. The Advance had actually come to rest on the bottom of
the Atlantic.

"Hurrah!" cried Tom. "Let's get on the diving suits, dad,
and walk about on land under water for a change."

"No," said Mr. Swift soberly. "We will hardly have time
for that now. Besides, the suits are not yet fitted with the
automatic air-tanks, and we can't use them. There are still
some things to do before we start on our treasure cruise.
But I want to see how the plates are standing this
pressure."

The Advance was made with a triple hull, the spaces
between the layers of plates being filled with a secret
material, capable of withstanding enormous pressure, as were
also the plates themselves. Mr. Swift, aided by Mr. Jackson
and Captain Weston, made a thorough examination, and found
that not a drop of water had leaked in, nor was there the
least sign that any of the plates had given way under the
terrific strain.

"She's as tight as a drum, if you will allow me to make
that comparison," remarked Captain Weston modestly. "I
couldn't ask for a dryer ship."

"Well, let's take a look around by means the searchlight
and the observation windows, and then we'll go back,"
suggested Mr. Swift. "It will take about two days to get the
stores and provisions aboard and rig up the diving suits;
then we will start for the sunken treasure.

There were several powerful searchlights on the Advance,
so arranged that the bow, stern or either side could be
illuminated independently. There were also observation
windows near each light.

In turn the powerful rays were cast first at the bow and
then aft. In the gleams could be seen the sandy bed of the
ocean, covered with shells of various kinds. Great crabs
walked around on their long, jointed legs, and Tom saw some
lobsters that would have brought joy to the heart of a
fisherman.

"Look at the big fish!" cried Mr. Damon suddenly, and he
pointed to some dark, shadowy forms that swam up to the
glass windows, evidently puzzled by the light.

"Porpoises," declared Captain Weston briefly. a whole
school of them."

The fish seemed suddenly to multiply, and soon those in
the submarine felt curious tremors running through the whole
craft.

"The fish are rubbing up against it," cried Tom. "They
must think we came down here to allow them to scratch their
backs on the steel plates."

For some time they remained on the bottom, watching the
wonderful sight of the fishes that swam all about them.

"Well, I think we may as well rise," announced Mr. Swift,
after they had been on the bottom about an hour, moving here
and there. "We didn't bring any provisions, and I'm getting
hungry, though I don't know how the others of you feel about
it."

"Bless my dinner-plate, I could eat, too!" cried Mr.
Damon. "Go up, by all means. We'll get enough of under-water
travel once we start for the treasure."

"Send her up, Tom," called his father. "I Want to make a
few notes on some needed changes and improvements."

Tom entered the lower pilot house, and turned the valve
that opened the tanks. He also pulled the lever that started
the pumps, so that the water ballast would be more quickly
emptied, as that would render the submarine buoyant, and she
would quickly shoot to the surface. To the surprise of the
lad, however, there followed no outrushing of the water. The
Advance remained stationary on the ocean bed. Mr. Swift
looked up from his notes.

"Didn't you hear me ask you to send her up, Tom?" he
inquired mildly.

"I did, dad, but something seems to be the matter," was
the reply.

"Matter? What do you mean?" and the aged inventor hastened
to where his son and Captain Weston were at the wheels,
valves and levers.

"Why, the tanks won't empty, and the pumps don't seem to
work."

"Let me try," suggested Mr. Swift, and he pulled the
various handles. There was no corresponding action of the
machinery.

"That's odd," he remarked in a curious voice "Perhaps
something has gone wrong with the connections. Go look in
the engine-room, and ask Mr. Sharp if everything is all
right there."

Tom made a quick trip, returning to report that the
dynamos, motors and gas engine were running perfectly.

"Try to work the tank levers and pumps from the conning
tower," suggested Captain Weston. "Sometimes I've known the
steam steering gear to play tricks like that."

Tom hurried up the circular stairway into the tower. He
pulled the levers and shifted the valves and wheels there.
But there was no emptying of the water tanks. The weight and
pressure of water in them still held the submarine on the
bottom of the sea, more than a mile from the surface. The
pumps in the engine-room were working at top speed, but
there