"Is it still producing?" Tom questioned.

"Yes, better than ever. But that's all the good it does my uncle. He is ill, discouraged, and despondent. All his fortune was eaten up in prospecting, and he depended on the gusher to make him rich again. And now, because of a rascally partner, he may be doomed to die a poor man. Of course we will always help him, but you know what it is to be dependent on relatives."

"I can imagine," conceded Tom. "It is tough luck! I wish I could help, and perhaps I can after I get back from this trip."

"The only way you or any one could help, would be to get back my uncle's missing papers," said Mary. "And as he himself isn't sure what became of them, it seem hopeless."

"It does," Tom agreed. "But wait until I get back."

"I wish you weren't going," sighed Mary.

"So do I—more than a little," was Tom's remark. "I'm sorry I ever let Mr. Damon persuade me to go into this deal with Dixwell Hardley!"

Mary sat bolt upright on the couch.

"What name did you say?" she cried.

"Dixwell Hardley," repeated Tom. "That's he name of the man who claims to know where the wreck of the Pandora lies. He says she has two millions or more in gold on board, and I'm to get half."

"Well!" exclaimed Mary, with spirit, "if you don't get any bigger share out of the wreck than my uncle got out of the oil well, you won't be doing so very nicely, Tom."

"What do you mean?" asked the young inventor. "What has the oil well to do with recovering gold from the wreck?"

"A good deal, I should say," answered the girl, "seeing that the same man is mixed up in both."

"What same man?"

"Dixwell Hardley!"

"Is he the man who cheated your uncle?" cried Tom.

"I won't say that he cheated him," said Mary. "But Dixwell Hardley is the man who furnished the money when my uncle went into partnership with him to locate oil wells in Texas. The oil wells were located, Mr. Hardley got his share, and my uncle got nothing. And just because he can't prove there was a legal partnership! I hope you won't have the same experience with Mr. Hardley, Tom."

"Whew!" whistled the young inventor. "This is news to me! I can say one thing, though. Mr. Hardley doesn't take a dollar out of that wreck unless I get one to match it. I think I hold the best cards on this deal. But, Mary, are you sure it's the same man?"

"Pretty sure. Wait, I'll call my father and make certain," she answered, and as she went from the room to summon Mr. Nestor, Tom felt a vague sense of uneasiness.



CHAPTER XI

BARTON KEITH'S STORY

"What's this Mary tells me, Tom?" asked Mr. Nestor, as he followed his daughter back into the room.

"You mean about Dixwell Hardley?"

"Yes. Do you suppose he can be the same man who has so meanly treated my brother-in-law?"

"I wouldn't want to say, Mr. Nestor, until you describe to me the Mr. Hardley you know. Then I can better tell. But from what little I have seen of the man to whom I was introduced by my friend Mr. Damon, I'd say, off hand, that he was capable of such action."

"Does Mr. Damon know this Mr. Hardley well?" asked Mrs. Nestor, who accompanied her husband.

"I wouldn't say that he did," Tom replied. "I don't know just how Mr. Damon met this chap—I think it was in a financial way, though."

"Well, if it's the same Mr. Hardley, I'll say he has some queer financial ways," said Mr. Nestor. "Now let's see if we can make the two jibe. Describe him, Tom."

This the young inventor did, and when this description had been compared with one given of the Mr. Hardley with whom Mr. Keith once was associated, Mrs. Nestor said:

"It surely is the same man! The Mr. Hardley who wants you to get wealth from the bottom of the ocean, Tom, is the same fellow who is keeping my brother out of the oil well property! I'm sure of it!"

"It does seem so," Tom agreed. "Dixwell Hardley is not a usual name; but we must be careful In spite of its unusualness there may be two very different men who have that name. I think the only way to find out for certain is to see Mr. Keith. He'd know a picture of the Dixwell Hardley who, he claims, cheated him, wouldn't he?"

"Indeed he would!" exclaimed Mrs. Nestor. "But where could we get a picture of your Mr. Hardley? I call him that, though I don't suppose you own him, Tom," and she smiled at her future son-in-law.

"No, I don't own him, and I don't want to," was Tom's answer. "But I happen to have a picture of him. I made him furnish me with proofs that he was on the Pandora at the time she foundered in a gale, and among the documents he gave was his passport. It has his picture on. I have it here."

Tom drew the paper from his pocket. In one corner was pasted a photograph of the man who had been introduced to Tom by Mr. Damon.

"It looks like the same man my brother described," said Mrs. Nestor, "but of course I couldn't be sure."

"There is only one way to be," Tom stated, "and that is to show this picture to Mr. Keith. Where is he?"

"Ill at his home in Bedford," answered Mrs. Nestor.

"Then we'll go there and see him!" declared Tom.

"But it's a hundred miles from here!" exclaimed Mary. "And you are leaving on your submarine trip the first thing in the morning, Tom!"

"No, I'm not leaving until I settle this matter," declared the young inventor. "I'm not going on an undersea voyage with a man who may be a cheater. I want this matter settled. I'll postpone this trip until I find out. A day's delay won't matter."

"But it will take longer than that," said Mr. Nestor. "Bedford is a small place, and there's only one train a day there. You'll lose at least three days Tom, if you go there."

"Not necessarily," was the quick answer. "I can go by airship, and make the trip in a little over an hour. I can be back the same day, perhaps not in time to start our submarine trip, as Mr. Keith may be too ill to see me. But I won't lose much time in my Air Scout.

"Mary, will you go with me to see your uncle? We'll start the first thing in the morning and I'll show him this picture. Will you go?"

"I will!" exclaimed the girl.

"Good!" cried Tom. "Then I'll make preparations. I don't want to form any rash judgment, so we'll make certain; but it wouldn't surprise me a bit to have it turn out that the Dixwell Hardley who wants me to help him recover the Pandora treasure is the same one who is trying to cheat Mr. Keith."

Early the next morning, when Tom arose in his own home, he met Mr. Damon and Mr. Hardley, both of whom were guests at the Swift house, pending the beginning of the undersea trip.

"Well, Tom," began the eccentric man, "we have good weather for the start. Bless my rubber boots! Not that it much matters, though, what sort of weather we have when we're in the submarine. But I always like to start in the sunshine."

"So do I," agreed Mr. Hardley. "I suppose we'll get off early this morning," he added.

"We'll go to the dock in the auto, as usual, shall we not?" he asked.

"We aren't going to start this morning," said Tom, as he sat down to breakfast.

"Not going to start this morning!" exclaimed Mr. Hardley. "Why—why—"

"Bless my alarm clock!" voiced Mr. Damon, "has anything happened, Tom? No accident to the M. N. 1 is there? You aren't backing out now, at the last minute, are you?"

"Oh, no," was the easy answer. "We'll go, as arranged, but not today. I had some unexpected news last night which necessitates making a trip this morning. I expect to be back tonight, if all goes well, and we'll start tomorrow morning instead of this. It's a matter of important business."

"Well, I don't know that we can find fault with Mr. Swift for attending to business," said Mr. Hardley, with a short laugh. "Business is what keeps the world moving. And we are a little ahead of our schedule, as a matter of fact. May I ask where you are going, Mr. Swift?"

"To Bedford, to call on a Mr. Barton Keith," answered Tom quickly, looking the adventurer straight in the eyes.

Mr. Hardley was a good actor, or else he was a perfectly innocent man, for he showed not the least sign of perturbation.

"Oh, Bedford," he remarked. "Don't know that I ever heard of the place."

"Or Mr. Keith, either?" asked Tom, a bit sharply.

"No, certainly not. Why should I?" he asked, boldly.

"I didn't know," Tom replied. "I'm sorry to postpone our trip, but it's necessary," he added. "I'll be back as soon as I can. Everything is in readiness, so there will be no delay."

Tom made a hurried meal, and then, giving Ned a hint of what was in the wind, but cautioning him to say nothing about it, Tom had the small Air Scout brought out, and in that he flew over to Mary's home.

He found her waiting for him, and, after being duly cautioned by her mother to "be careful," though whether that was of any value or not is possibly debatable, the small, speedy craft again took the air.

"You haven't heard anything from your uncle since last night, have you?" asked Tom, as they flew along.

"Yes," answered Mary, "mother had a letter. He is worse, if anything, and the doctor says the only thing that will save him is the knowledge that the oil-well matter has turned out right and that my uncle will get his share of the wealth."

"That's too bad!" sympathized Tom. "I hope we can make it turn out that way. If the two Dixwell Hardley chaps are the same it may be that I can do something for your uncle. If not—we'll have to wait and see."

It was not difficult for Tom and Mary to talk while in the aeroplane, as it was almost noiseless. In due time, Bedford was reached without mishap, and Tom and Mary were soon at the home of her uncle.

An explanation to the housekeeper and an inspection on the part of the nurse, brought forth permission for Tom to see the patient. Though he had never known Mr. Keith he could see that the man's health was indeed fast waning.

Wasting little time in preliminaries, the object of the visit was told and Tom showed the passport photograph of Dixwell Hardley.

"Is that the man who cheated you on the oil-well deal?" asked the young inventor.

"I won't admit he has yet cheated me, but he is trying to!" exclaimed Mr. Keith, with something of a return of his former spirit. "If I ever get off my back I'm going to fight him tooth and nail. But that's the same scoundrel! He got me to locate the wells, and when they panned out big—bigger than either of us dreamed—he turned me out cold. He denied he had ever offered to share with me, and said I was only working for monthly wages! Why, sometimes I didn't get even that!"

"How did he get the best of you?" asked Tom.

"By making away with or hiding the papers by which I could prove our partnership and my right to half a share in all the wells," answered Mary's uncle. "Yes, that's the same man all right. I'd know his face anywhere, and he ha& the same name."

"He isn't going under a false name, that's sure," agreed Tom. "He must be a bold chap."

"He is—bold and unscrupulous! That's what makes him so successful in his own way!" declared Mr. Keith. "And so you are working with him! Well, I'm sorry for you."

"I'm not exactly working with him," replied Tom. "As a matter of fact, I'm sorry I ever agreed to look for this wreck."

He told the details of the pending treasure-trove expedition, and mentioned it as his belief that Mr. Damon had been mistaken in his estimate of Mr. Hardley.

"But, so far, Mr. Damon is quite taken with him," Tom went on. "Now, Mr. Keith, if it isn't too much for you, I should like to hear all the particulars."

Thereupon Mary's uncle told his story. It was a long one. After many hardships in life, which Mr. Keith related in some detail to Tom, the oil-well prospector at last fell in with Dixwell Hardley. Then followed the combination of interests.

"We are actually partners," declared Mr. Keith. "I agreed to do the work, and he agreed to furnish the money. I must say this for him, that he kept to that end of the bargain. He supplied the money to locate and drill the wells, but I got very little of it personally. And I fulfilled my end of it. I discovered the wells. Then, when the break came, and I wanted to be rid of the man—for I caught him in some crooked transactions—he surprised me by telling me to get out. I asked for my share of the oil-well stock, and was told I was not entitled to any.

"I put up a fight, naturally, and took the matter to court. But when it came to trial Dixwell Hardley did not appear, and, though I won a technical victory over him, I never got any money."

"Where was he during the trial?" asked Tom.

"At sea, I believe."

"At sea?"

"Yes, he was mixed up in some South American revolution, I heard."

"A South American revolution!" exclaimed Tom, and a great light came to him.

"Yes," went on Mary's uncle. "He was always that kind—mixing up in anything he thought would produce money. He didn't make out very well in the revolution business, so I understood. The revolutionary party was beaten, or they lost their shipment of arms, or something like that. At any rate, Dixwell Hardley had a narrow escape with his life when a ship went down, and from then on I've been trying to get him to restore my rights to me."

"Did he have the papers that would prove you were entitled to a half share in the oil wells?" asked Tom.

"He certainly did!" said the sick man, who was obviously being weakened by this long and exhausting talk. "At first I was not sure of what happened, but now I am positive he stole the papers and took them to sea with him. What happened to them after that I don't know. But if I had Dixwell Hardley here—now—I—I'd—"

Mr. Keith fell back in a faint on the bed, and, in great alarm, Tom summoned the nurse.



CHAPTER XII

IN DEEP WATERS

Mary Nestor, as well as Tom Swift, felt great alarm over the condition of Mr. Keith. But the nurse, after reviving him, said:

"He is in no special immediate danger. Talking about his trouble overstrained him, but in the end it may do him good."

"Then will he get well?" asked Mary.

"He may," was the noncommittal answer. "His recovery would be hastened, however, if his mind could be relieved. He keeps worrying about the loss of his papers that proved his share in the Texas oil wells. Until they can be given back to him he is bound to suffer mentally, and of course that effects him physically."

"Oh, if we only could do something!" murmured Mary.

"Perhaps we can," said Tom in a low voice. "I've learned something these last few hours. I don't want to promise too much, but I think I begin to see how matters lie. There, he's rousing. Speak to him, Mary."

Mr. Keith opened his eyes, and smiled at his niece.

"Did I dream it," he asked in a low voice, "or was there some young man with you, Mary, my dear, to whom I was telling my troubles about the oil-well papers?"

"You didn't dream it, Uncle," Mary answered. "You were talking to Tom Swift. Here he is," and Tom came forward.

"Oh, yes, I remember now," said Mr. Keith passing his hand wearily over his eyes. "I thought, for a moment, that he had recovered my papers for me. But that was a dream, I'm sure."

"It may not be, Mr. Keith!" exclaimed Tom.

"May not be? What do you mean?"

"I mean," replied the young inventor, "that I am much interested in what you have told me. Now that I have proved that the Dixwell Hardley who is to sail with me is the same one who has treated you so shabbily, I think I understand the truth. I don't want to make a promise that I may not be able to carry out, but I am going to watch this man while he's on the submarine with me."

"Then you are going on with the voyage, Tom?" asked Mary.

"I shall have to," he said. "I have entered into an agreement with this man and I'm not going to break my contract, no matter what he does. But I think I know what his game is. Mr. Keith, I'm going to ask you to keep quiet about this matter until I come back from the treasure search. I may then have some news for you."

"I hope you do, young man, I hope you do!" exclaimed the oil contractor, with more energy than he had previously shown. "It means a lot, at my age, to lose a small fortune. If I were well and strong I'd tackle this Dixwell Hardley myself, and make him give up the papers I'm sure he has hidden away. He has them, I'm positive."

"Well, he may not have them, but perhaps he knows where they are," said Tom. "And I'm going to make it my business to watch him and see if I can find out his secret. I won't let him know I've heard from you. I'll apply the old saying of giving him plenty of rope, and I'll watch what happens.

"Now, Mr. Keith, take care of yourself. Mary and I must be getting back. Try not to worry, and I'll do my best for you," Tom concluded.

Mary added a few words of comfort and encouragement to her uncle, and then she and Tom took leave of him, flying back to Shopton in the speedy Air Scout.

"What are you going to do, Tom?" asked Mary, as he left her at her home, having told Mr. and Mrs. Nestor his part in the visit to Barton Keith.

"I'm going to start on the submarine voyage tomorrow," was the answer of the young inventor.

"Do you really believe there is a treasure ship?"

"Well, I've satisfied myself that a ship named the Pandora sunk about where Hardley says it did, and she had some treasure on board. Whether it's just the kind he has told me it was I don't know. But I'm going to find out."

"Then you'll be saying goodbye for a long time," observed Mary, rather wistfully.

"Oh, it may not be for so very long," and Tom tried to speak cheerfully. "I'll bring you back some souvenirs from the bottom of the sea," he added with a laugh.

"Bring me back—yourself!" said Mary in a low voice, and then she hurried away.

By appointment Tom met Mr. Damon and Mr. Hardley at the submarine dock the next morning. Everything had been made ready for the start, postponed from the day before. Mr. Hardley's estimated share of the expenses had been deposited in a bank, to be paid over later.

"Well, are we really going this time, or are you going to delay again?" asked the gold seeker, and his voice lacked a pleasant tone.

"Oh, were going this time!" exclaimed Tom. "And I hope everything turns out the way I want it to," he added meaningly.

"We'll find the treasure on the ship all right, if we can find the ship," said Mr. Hardley. "That part is your job, Mr. Swift."

"And I'll find her if she's where you say she went down," answered Tom. "Now then, as soon as Ned comes we'll start."

Ned Newton had been intrusted with some last-moment messages, but he arrived a little later, and hurried on board the M. N. 1 which lay at her dock, just afloat.

"All aboard!" called Tom, when he saw his financial manager coming down the pier. "We're ready to start now."

"Bless my fountain pen!" exclaimed Mr. Damon, "but we ought to do something, Tom—sing a song, make a speech or something, oughtn't we?"

"We'll sing a song of victory when we come back," replied Tom, with a laugh. "Everything all right at home, Ned?" he asked, for his chum had just come on from Shopton.

"Yes; your father sent his regards, but he told me to make a last appeal to you to install a gyro-scope rudder."

"It's too late for that now," said Tom. "He attaches, I think, too much importance to that device. I shan't need it with the improvements I have made to the craft. Get aboard!"

Ned climbed down the hatchway, which, however, was not closed, as it was decided to navigate the craft on the surface until it was necessary to submerge her because of too rough water, or when the vicinity of the wreck was reached.

"Though we will go down to the bottom when we get to the Atlantic for the purpose of testing her in deep water," decided Tom. "Most of the time we'll steam on the surface, for we'll save our batteries that way, and it's more comfortable breathing natural air."

So, with part of her deck above the surface, the M. N. 1 began her voyage, sent on her way by the cheers of the small force of Tom's workmen at the submarine plant. The general public was not admitted, for the object of the quest was kept secret from all save those immediately interested.

"Rad, him be plenty mad he not come," said Koku to Tom, as the giant moved about the cabin, putting things to rights.

"Well, don't start crowing over him until we get back," warned the young inventor. "He may have the laugh on us."

"Rad no laugh," declared Koku. "Rad him too mad dat I come on trip."

"A submarine voyage is no place for old, faithful Eradicate," murmured Tom. "He's better off looking after my father."

The first part of the trip was without incident of moment. No mishap attended the voyage of the M. N. 1 down the river, out into the bay, and so on to the great Atlantic.

Fairly good time was made, as there was no particular object in speeding, and on the second day after leaving the dock Tom gave orders for the hatch to be closed, the deck cleared, and everything made tight and fast.

"What's up?" asked Ned, hearing the instructions passed around.

"We're approaching deep water," was the answer. "I'm going to submerge."

A little later, by means of her diving rudders, aided also by the tanks, the M. N. 1 began to sink. Down, down, down she went.

"Now I'll be able to show you some pretty sights, Mr. Hardley," said Tom, as he and his friends entered the forward compartment, while the steel shutters were rolled back from the heavy glass windows. "We'll be in deep waters presently."

Ten minutes later the depth gauge showed that they were down about three hundred feet, and that is pretty deep for a submarine. But Tom's boat was capable of even greater depths than that.

At first there was nothing much to observe save the opal-tinted water illuminated by the powerful lights of the submarine. Small, and evidently frightened, fish darted to and fro, but there was nothing especially to attract the attention of Tom and his friends, who had made much more sensational trips than this under water.

Mr. Hardley, however, was fascinated, and kept close to the observation windows.

"Are there any wrecks around here?" he asked Tom.

"Possibly," was the answer. "Though they do not contain any treasure, I imagine—brick schooners or cargo boats would be about all."

The submarine went deeper, plowing her way through the Atlantic at a depth of more than three hundred and fifty feet, for Tom wanted to subject her to a good test.

Suddenly Mr. Hardley, who was now alone at the window on the port side, uttered a cry of alarm.

"Look! Look!" he fairly shouted. "We're surrounded by a school of sharks! What monsters! Are we in danger?"



CHAPTER XIII

THE SEA MONSTER

Tom Swift, who had been making readings of the various gauges, taking notes for future use, and otherwise busying himself about the navigation of his reconstructed craft, turned quickly from the instrument board at the cry from Mr. Hardley. The gold-seeker, with a look of terror on his face, had recoiled from the observation windows.

"Bless my hat band!" cried Mr. Damon. "Look, Tom!"

They all turned their attention to the glass, and through the plates could be seen a school of giant fishes that seemed to be swimming in front of the submarine, keeping pace with it as though waiting for a chance to enter.

"Are we well protected against sharks, Mr. Swift?" demanded the adventurer. "Are these sea monsters likely to break, the glass and get in at us?"

"Indeed not!" laughed Tom. "There is absolutely no danger from these fish—they aren't sharks, either."

"Not sharks?" cried Mr. Hardley. "What are they, then?"

"Horse mackerel," Tom answered. "At least that is the common name for the big fish. But they are far from being sharks, and we are in no danger from them."

"Oh!" exclaimed Mr. Hardley, and he seemed a little ashamed of the exhibition of fear he had manifested. "Well, they certainly seem determined to follow us," he added.

The big fish were, indeed, following the submarine, and it required no exertion on their part to maintain their speed, since below the surface the M. N. 1 could not move very fast, as indeed no submarine can, due to the resistance of the water.

"They do look as though they'd like to take a bite or two out of us," observed Ned. "Are they dangerous, Tom?"

"Not as a rule," was the answer. "I don't doubt, though, but if a lone swimmer got in a school of horse mackerel he'd be badly bitten. In fact, some years ago, when there was a shark scare along the New Jersey coast, some fishermen declared that it was horse mackerel that were responsible for the death and injury of several bathers. A number of horse mackerel were caught and exhibited as sharks, but, as you can easily see, their mouths lack the under-shot arrangement of the shark, and they are not built at all as are the man-eaters."

"Bless my toothbrush!" exclaimed Mr. Damon. "Still, between a horse mackerel and a shark there isn't much choice!"

Mr. Hardley, with a shudder, turned away from the glass windows, and Tom glanced significantly at Ned. It was another exhibition of the man's lack of nerve.

"We'll have trouble with him before this voyage is over," declared the young inventor to his chum, a little later.

"What makes you think so?" asked Ned.

"Because he's yellow; that's why. I thought him that once before, and then I revised my opinion. Now I'm back where I started. You watch—we'll have trouble."

"Well, I guess we can handle him," observed the financial manager.

"I'm going a little deeper," announced Tom, toward evening on the first day of the voyage on the open ocean. "I want to see how she stands the pressure at five hundred feet. I feel certain she will, and even at a greater depth. But if there's anything wrong we want to correct it before we get too far away from home. We're going down again, deeper than before."

A little later the submarine began the descent into the lower ocean depths. From three hundred and fifty feet she went to four hundred, and when the hand on the gauge showed four hundred and fifty there was a tense moment. If anything went wrong now there would be serious trouble.

But Tom Swift and his men had done their work well. The M. N. 1 stood the strain, and when the gauge showed four hundred and ninety feet Mr. Damon gave a faint cheer.

"Bless my apple dumpling, Tom!" he replied, "this is wonderful."

"Oh, we've been deeper than this," replied the young inventor, "but under different conditions. I'm glad to see how well she is standing it, though."

Suddenly, as the needle pointer on the depth gauge showed five hundred and two feet, there came a slight jar and vibration that was felt throughout the craft.

"What's that?" suddenly and nervously cried Mr. Hardley. "Have we struck something?"

"Yes, the bottom of the ocean," answered Tom quietly. "We are now on the floor of the Atlantic, though several hundred miles, and perhaps a thousand, from the treasure ship. We bumped the bottom, that's all," and as he spoke he brought the submarine to a stop by a signal to the engine room.

And there, as calmly and easily as some of the masses of seaweed growing on the ocean floor around her, rested the M. N. 1. It was a test of her powers, and well had she stood the test, though harder ones were in store for her.

And inside the submarine Tom and his party were under scarcely greater discomfort than they would have been on the surface. True, they were confined to a restricted space, and the air they breathed came from compression tanks, and not from the open sky. The lights had to be kept aglow, of course, for it was pitch dark at that depth. The sunlight cannot penetrate to more than a hundred feet. But sunlight was not needed, for the craft carried powerful electric lights that could illuminate the sea in the immediate vicinity of the submarine.

"Are you going to stay here long?" asked Mr. Hardley, when Tom had spent some time making accurate readings of the various instruments of the boat. "Of course, I realize that you are the commander, but if we don't get to the treasure ship soon some one else may loot her before we have a chance. She's been given up as a hopeless task more than once, but the lure of the millions may attract another gang."

"I want to stay here until I make sure that nothing is leaking and that everything is all right," answered the young inventor. "This is a test I have not given her since the rebuilding. But I think she is coming through it all right, and we can soon start off again. Before we do, though, I want to try the new diving outfit. Ned, are you game for it now? This is a little deeper than you have gone out in for some time, but—"

"Oh, I'm game!" exclaimed the young financial manager. "Get out the suit, Tom, and I'll put it on. I'll go for a stroll on the bottom of the sea. Who knows? Perhaps I may pick up a pearl."

"Pearls aren't found in these northern waters, any more than are sharks," said Tom with a laugh. "However, I'll have the suits made ready. I'll send Koku with you, and I'll stay in this time. Mr. Damon, do you want to go out?"

"Not this time, Tom," answered the eccentric man. "My heart action isn't what it used to be. The doctor said I mustn't strain it. At a depth not quite so great I may take a chance."

"How about you, Mr. Hardley?" asked Tom. "Do you want to put on one of my portable diving suits and walk around on the bottom of the sea?"

"I—I don't believe I've had enough experience," was the hesitating answer. "I'll watch the others first."

Tom felt that it would be this way, but he said nothing. He ordered the diving suits made ready, a special size having been built for the giant, and soon preparations were under way for the two to step outside the craft.

Those who have read of Tom Swift's submarine boat know how his special diving outfit was operated. Instead of the diver being supplied with the air through a hose connected with a pump on the surface, there was attached to the suit a tank of compressed air, which was supplied as needed through special reducing valves.

The diving dress, too, was exceptionally strong, to withstand the awful pressure of water at more than five hundred feet below the surface. The usual rubber was supplemented by thin, reinforced sheets of steel, and this feature, together with an auxiliary air pressure, kept the wearer safe.

Thus Ned and Koku could leave the submarine, walk about on the floor of the ocean as they pleased, and return, unhampered by an air hose or life line. In dangerous waters, infested by sea monsters, weapons could be carried that were effective under water. The diving suit was also provided with a powerful electric light operated by a new form of storage current, compact and lasting.

"Well, I think we're all ready," announced Ned, as he and Koku were helped into their suits and they waited for the glass-windowed helmets to be put on. Once these were fastened in place talk would have to be carried on with the outside world by means of small telephones or by signals.

"Give me axe!" exclaimed Koku, as some of the sailors were about to put his helmet in place.

"What do you want of an axe?" Tom asked.

"Maybe so one them cow fish come along," explained the giant. "Koku whack him with axe."

"He means horse mackerel," laughed Ned. "Give him the axe, Tom. I don't like the looks of those fish, either. I'll take a weapon myself."

Two keen axes were handed to the divers, their helmets were screwed on, and they immediately began breathing the compressed air carried in a tank on their shoulders.

Slowly and laboriously they walked to the diving chamber. Their progress would be easier in the water, which would buoy them up in a measure. Now they were heavily weighted.

To leave the submarine the divers had to enter a steel chamber in the side of the craft. This craft contained double doors. Once the divers were inside the door leading to the interior of the submarine was hermetically closed. Water from outside was then admitted until the pressure was equalized. Then the outer door was opened and Ned and Koku could step forth.

They entered the chamber, the door was closed tightly and then Tom Swift turned the valve that admitted the sea water. With a hiss the Atlantic began rushing in, and in a short time the outer door would be opened.

"If you'll come around to the observation windows you can see them," said Tom, when a look at the indicators told him Ned and Koku had stepped forth.

To the front cabin he and the others betook themselves, and when the interior lights were turned out and the exterior ones turned on they waited for a sight of the two divers.

"Bless my pickle bottle!" cried Mr. Damon, "there they are, Tom."

As he spoke there came into view, moving slowly, Ned and Koku. Their portable lights were glowing, and then, in order to see them better, Tom turned out the exterior searchlights. This made the two forms, in their rather grotesque dress, stand out in bold relief amid the swirling green waters of the Atlantic.

Ned and the giant moved slowly, for it was impossible to progress with any speed wader that terrific pressure. They looked toward the submarine and waved their hands in greeting. They had no special object on the ocean floor, except to try the new diving dress, and it seemed to operate successfully. Ned made a pretense of looking for treasure amid the sand and seaweed, and once he caught and held up by its tail a queer turtle. Koku stalked about behind Ned, looking to right and left, possibly for a sight of some monster "cow fish."

"They're coming back in, I think," remarked Tom, when he saw Ned turn and start back for the side of the craft, where, amidships, was located the diving chamber. "They're satisfied with the test."

Suddenly Koku was seen to glide to the side of Ned, and point at something which none of the observers in the M. N. 1 could see. The giant was evidently perturbed, and Ned, too, showed some agitation.

"Bless my rubber shoes! what's the matter?" cried Mr. Damon.

"I don't know," answered Tom. "Perhaps they have sighted a wreck, or something like that."

"Look! It's a sea monster!" cried Mr. Hardley. "I can see the form of some great fish, or something. Look! It's coming right at them!"

As he spoke all in the observation chamber saw a great, black form, as if of some monster, move close to the two divers.



CHAPTER XIV

IN STRANGE PERIL

"What is it, Tom? What is it?" cried Mr. Damon, not stopping in this moment of excitement to bless anything. "What is going to attack Ned and Koku?"

"I don't know," answered the young inventor. "It's some big fish evidently. I must get to the diving chamber!"

He gave a quick glance through the observation windows. Ned and the giant were moving as fast as they could toward the side of the craft where they could enter. The black, shadowy form was nearer now, but its nature could not be made out.

Calling to his force of assistants, Tom stood ready to let his chum and Koku out of the diving chamber as soon as the water should have been pumped from it.

A little later, as they all stood waiting in tense eagerness, there came a signal that the two divers had entered the side chamber. Quickly Tom turned the lever that closed the outer door.

"They're safe!" he exclaimed, as he started the pumps to working. But even as he spoke they felt a jar, and the submarine rolled partly over as if she had collided with some object. Yet this could not be, as she was stationary on the floor of the ocean.

"Bless my cake of soap, Tom!" cried Mr. Damon, "what in the world is that?"

"If it's an accident!" exclaimed Mr. Hardley, "I think it ought to be prevented. There have been too many happenings on this trip already. I thought you said your submarine was safe for underwater trips!" he fairly snapped at Tom.

The young inventor gave one look at the irate man who was coming out in his true colors. But it was no time to rebuke him. Too much yet remained to be done. Ned and Koku were still in the chamber and protected from some unknown sea monster by only a comparatively thin door. They must be inside to be perfectly safe.

Tom speeded up the pumps that were forcing the water from the chamber so the inner door could be opened. Eagerly he and his men watched the gauges to note when the last gallon should have been forced out by the compressed air. Not until then would it be safe to let Ned and Koku step into the interior of the craft.

The submarine had not ceased rolling from the force of the blow she had received when there came another, and this time on the opposite side. Once more she rolled to a dangerous angle.

"Bless my tea biscuit!" cried Mr. Damon, "what is it all about, Tom Swift?"

"I don't know," was the low-voiced answer, "unless a pair of monsters are attacking us on both sides alternately. But we'll soon learn. There goes the last of the water!"

The gauge showed that the diving chamber was empty. Quickly the inner doors were opened, stud, with their suits still dripping from their immersion in the salty sea, Ned and Koku stepped forth. In another moment their helmets were loosed from the bayonet catches, and they could speak.

"What was it, Ned?" cried Tom.

"Big fish!" answered Koku.

"Two monster whales!" gasped Ned. "We barely got away from them! They're ramming the sub, Tom!"

As he spoke there came a blow on the port side, greater than either of the two preceding ones. Those in the M. N. 1 staggered about, and had to hold on to objects to preserve their footing.

"Both at the same time!" cried Ned. "The two whales are coming at us both at once!"

This was evidently the case. Tom Swift quickly hurried to the engine room.

"What are you going to do?" asked Mr. Hardley. "You ought to do something! I'm not going to be killed down here by a whale. You've got to do something, Swift! I've had enough of this!"

Tom did not deign an answer, but hurried on. Mr. Damon followed him, having seen that some of the sailors were helping Ned and Koku out of the diving suits.

"Are we in any danger, Tom?" asked the eccentric man.

"Yes; but I think it is easily remedied," was the answer. "We'll go up to the surface. I don't believe the whales will follow us. Or, if they do, they can't do much damage when we are in motion. It's because we are stationary and they are moving that the blows seem so violent. Unless they collide head on with us, in the opposite direction to ours, we ought to be able to get clear of them. If they persist in following us—"

He paused as he pulled over the lever that would send the M. N. 1 to the surface.

"Well, what then?" asked Mr. Damon.

"Then we'll have to use some weapon, and I have several," finished the young inventor.

A few moments later the craft was in motion, not before, however, she was struck another blow, but only a glancing one.

"We're puzzling them!" cried Tom.

Having done all that was possible for the time being, Tom hurried to the observation chamber, followed by the ethers. There Tom switched on the powerful lights. For a moment nothing was to be seen but the swirling, green water. Then, suddenly, a great shape came into view of the glass windows, followed by another.

"Whales!" cried Tom Swift. "And the largest I've ever seen."

It was true. Two immense specimens of the cetacean species were in front of the submarine, one on either bow, evidently much puzzled over the glaring lights. They were bow-heads, and immense creatures, and it would not take many blows from them to disable even a stouter craft than was the submarine.

But the motion of the undersea ship, the bright lights, and possibly the feel of her steel skin was evidently not to the liking of the sea monsters. One, indeed, came so close to the glass that he seemed about to try to break it, but, to the relief of all, he veered off, evidently not liking the look of what he saw.

Just once again, before the craft reached the surface, was there another blow, this time at the stern. But it was a parting tap, and none others followed.

"They've gone!" exclaimed Mr. Damon, as the whales vanished from the sight of those in the forward cabin.

"Have you any adequate protection against these monsters of the deep?" asked Mr. Hardley in a fault-finding voice. "I should think you would have taken precautions, Swift!"

He had dropped the formal "Mr." and seemed to treat Tom as an inferior.

"We have other protection than running away," said the young inventor quietly. "There are guns we can use, and, if the whales had been far enough away, I could have sent a small torpedo at them. Close by it would be dangerous to use that, as it would operate on us just as the depth bombs operated on the German submarines. However, I fancy we have nothing more to fear."

And Tom was right. When the surface was reached and the main hatch opened, the sea was calm and there was no sight of the whales. They evidently had had enough of their encounter with a steel fish, larger even than themselves.

"But they surely were monsters," said Ned, as he told of how he and Koku had sighted the animals; for a whale is an animal, and not a fish, though often mistakenly called one.

"Koku was for attacking them with his axe," went on Ned, "but I motioned to him to beat it. We wouldn't have stood a show against such creatures. They were on us before we noticed their coming, but I presume the big submarine attracted them away from us."

"It might have been the lights you carried that drew them," suggested Tom. "I am glad you came out of it so well."

Mr. Hardley seemed to recover some of his former manners, once the peril was passed, but his conduct had been a revelation to Mr. Damon.

"Tom," said the eccentric man in private to the young inventor, "I'm disgusted with that fellow. I don't see how I was ever bamboozled into taking up his offer."

"I don't, either," replied Tom frankly. "But we're in for it now. We've agreed to do certain things, and I'll carry out my end of the bargain. However, I won't put up with any of his nonsense. He's got to obey orders on this ship! I know more than he thinks I do!"

The next two days the M. N. 1 progressed along on the surface, and nothing of moment occurred. Then, as they neared southern waters, and Tom desired to make some observations of the character of the bottom, it was decided to submerge. Accordingly, one day the order was given.

Not until the gauge showed a hundred fathoms, or six hundred feet, did the craft cease descending, and then she came to rest on the bottom of the sea—a greater depth than she had yet attained on this voyage.

"How beautiful!" exclaimed Mr. Damon, when Tom turned on the lights and they looked out of the forward cabin windows. "How wonderful and beautiful!"

Well might he say that, for they were resting on pure white sand, and about them, growing on the bottom of this warm, tropical sea were great corals, purple and white, of wondrous shapes, waving plants like ferns and palms, and, amid it all, swam fish of queer shapes and beautiful colors.

"This is worth waiting for!" murmured Ned. "If only moving pictures of this could be taken in colors, it would create a sensation."

"Perhaps I may try that some day," said Tom with a smile. "But just now I have something else to do. Ned, are you game for another try in the diving dress? I want to see how it operates with a new air tank I've fitted on. Want to try?"

"Sure I'll go out," was the ready answer. "It's nicer walking around on this white sand than on the black mud where we saw the whales. You can see better, too."

A little later he and one of the sailors were outside the submarine, walking around in the diving dress, while Tom and the others watched through the glass windows. The new air tank seemed to be working well, for Ned, coming close to the window, signaled that he was very comfortable.

He walked around with the sailor, breaking off bits of odd-shaped coral to bring back to Tom. Suddenly, as those inside the craft looked out, they saw the sailor turn from Ned's side, and with a warning hand, point to something evidently approaching. The next instant a queer shape seemed to envelope Ned Newton, coming out from behind a ledge of weed-draped coral. And a cry went up from those in the submarine as Ned was seen to be enveloped in long, waving arms.

"An octopus!" cried Mr. Damon. "Bless my soul, Tom, an octopus has Ned!"

"No, it isn't that!" cried the young inventor hoarsely. "It's some other monster. It has only five arms—an octopus has eight! I've got to save Ned!"

And he hurried toward the diving chamber, while the others, in fascinated horror, looked at the diver who was in such strange peril.



CHAPTER XV

TOM TO THE RESCUE

Mr. Damon came to a pause in the compartment from which the diving chamber gave access to the ocean outside. Tom, standing before the sliding steel door, had summoned to him several of his men and was rapidly giving them directions.

"What are you going to do, Tom Swift?" asked the eccentric man.

"I'm going out there to save Ned!" was the quick answer. "He's in the grip of some strange monster of the sea. What it is I don't know, but I'm going to find out. Koku, you come with me!"

"Yes, Master, me come!" said the giant simply, as if Tom had told him to go for a pail of water instead of risking his life.

"Barnes, the electric gun!" cried the young inventor to one of his helpers, while others were getting out the diving suits.

"The electric gun!" exclaimed the man. "Do you mean the small one?"

"No, the largest. The improved one."

"Right, sir! Here you are!"

"Do you mean to say you are going out there, where that monster is, and attack it with a gun?" asked Mr. Hardley.

"That's what I'm going to do!" answered Tom, as he began to put on the suit of steel and rubber, an example followed by Koku.

"But you may be attacked by the monster! You may be killed! You are risking your life!" cried the gold seeker.

"I know it." Tom spoke simply. "Ned would do the same for me!"

"But hold on!" cried Mr. Hardley. "If you are killed there will be no one to navigate this boat to the place of the wreck! You can't desert this way!"

Tom gave the man one look of contempt. "You need have, no fears," he said. "This submarine is under international maritime laws. If I die, Captain Nelson, the next in command, takes charge, and the original orders will be carried out. If it is possible to get the gold for you it will be done. Now let me alone. I've got work to do!"

"Bless my apple cart, Tom, that's the way to talk!" exclaimed Mr. Damon, and he, too, for the first time, seemed ready to break with Hardley. "If I were a bit younger I'd go out with you myself and help save Ned."

"Koku and I can do it—if he's still alive!" murmured the young inventor. "Lively now, boys! Is that gun ready?"

"Yes, and doubly charged," was the answer. "Good! I may need it. Koku, take a gun also!"

"Me take axe, Master," replied the giant.

"Well, perhaps that will be better," Tom agreed. "If two of us get to shooting under the water we may hit one another. Quick, now! The helmets. And, Nash, you work the big searchlight!"

"Aye, aye, sir!" answered the sailor.

The helmets were now put on, and any further orders Tom had to give must come through the telephone, and it was by that same medium that he must listen to the talk of his friends. It was possible for the divers to talk and listen to one another while in the water by means of these peculiarly constructed telephones.

"All ready, Koku?" asked Tom.

"All ready, Master," answered the giant, as he grasped his keen axe.

The inner door of the diving chamber was now opened, and, the water having been pumped out of the chamber since Ned and the sailor had emerged, it was ready for Tom and Koku. They entered, the door was closed, and presently they felt the pressure of water all about them, the sea being admitted through valves in the outer door.

While this was going on Mr. Damon, the gold-seeker, and some of the crew and officers went into the forward chamber to observe the undersea fight against the monster that had attacked Ned.

Suddenly the waters glowed with a greatly increased light, and in this illumination it was seen that the monster, whatever it was, had almost completely enveloped Tom's chum with its five arms.

"What makes it possible to see better?" asked Mr. Damon.

"I've turned on the big searchlight," was the answer. "Mr. Swift had it installed at the last moment. It's the same kind he invented and gave to the government, but he retained the right to use it himself."

"It's a good thing he did!" exclaimed the eccentric man. "Now he can see what he's doing! Poor Ned! I'm afraid he's done for!"

"Look!" exclaimed one of the crew. "Norton, the sailor who went out with Mr. Newton, is trying to kill the monster with his spear!"

This was so. Ned's companion, armed with a lone pole to which he had lashed a knife, was stabbing and jabbing at the black form which almost completely hid Ned from sight. But the efforts of the sailor seemed to produce little effect.

"What in the world can it be?" asked Mr. Damon. "Tom says it isn't an octopus, and it can't be, unless it has lost three of its arms. But what sort of monster is it?"

No one answered him. The powerful searchlight continued to glow, and in the gleam Ned could be seen trying to break away from the grip of the Atlantic beast. But his efforts were unavailing. It was as if he was enveloped in a sort of sack, made in segments, so that they opened and closed over his head. About all that could be seen of him was his feet, encased in the heavy lead-laden boots. The form of the other sailor, who had gone out of the submarine with him, could be seen moving here and there, stabbing at the huge creature.

"Here comes Tom!" suddenly exclaimed Mr. Damon, and the young inventor, followed by the giant Koku, came into view. They had emerged from the diving chamber, walked around the submarine as it rested on the ocean floor, and were now advancing to the rescue. Tom carried his electric rifle, and Koku an axe.

So desperately was Norton engaged in trying to kill the sea beast that had attacked Ned, that for the moment he was unaware of the approach of Tom and Koku. Then, as a swirl of the water apprised him of this, he turned and, seeing them, hastened toward them.

"What is it?" Tom asked through the telephone, this information being given to the watchers in the submarine later, as all they could gather then was by what they saw. "What sort of monster is it?"

"A giant starfish!" answered Norton, speaking into his mouthpiece and the water serving as a transmitting medium instead of wires. "I never knew they grew so big! This one has its five arms all around Mr. Newton!"

"A starfish!" murmured Tom. This accounted for it, and, as he looked at the monster from closer quarters, he saw that Norton had spoken the truth.

Small starfish, or even large ones, two feet or more in diameter, may be seen at the seashore almost any time. Nearly always the specimens cast up on the beach are in extended form, either limp, or dead and dried. In almost every instance they are spread out just as their name indicates, in the conventional form of a star.

But a starfish alive, and at its business of eating oysters or other shell animals in the sea, is not at all this shape. Instead, it assumes the form of a sack, spreading its five radiating arms around the object of its meal. It then proceeds to suck the oyster out of its shell, and so powerful a suction organ has the starfish that he can pull an oyster through its shell, by forcing the bivalve to open.

And it was a gigantic starfish, a hundred times as large as any Tom had ever seen, that had Ned in its grip. The creature had doubtless taken the diver for a new kind of oyster, and was trying to open it. An octopus has suckers on the inner sides of its eight arms. A starfish has little feelers, or "fingers," arranged parallel rows on the inner side of its arms—thousands of little feelers, and these exert a sort of sucking action.

The gigantic starfish had attacked Ned from above, settling down on him so that the head of the diver was at the middle of the creature's body, the five arms, dropping over Ned in a sort of living canopy. And the arms held tightly.

"Come on, Koku, and you, too, Norton!" called Tom through his headpiece telephone. "We'll all attack it at once. I'll fire, and then you begin to hack it. The electric charge ought to stun it, if it doesn't kill the beast!"

Tom's new electric gun, unlike one kind he had first invented, did not fire an electrically charged bullet. Instead it sent a powerful charge of electricity, like a flash of lightning, in a straight line toward the object aimed at. And the current was powerful enough to kill an elephant.

Bracing his feet on the white sand, which gleamed and sparkled in the glare of the searchlight, Tom aimed at the gigantic starfish which had enveloped Ned. Standing on either side of him, ready to rush in and attack with axe and lance, were Koku and Norton.

For an instant Tom hesitated. He was wondering whether the powerful electric charge might not penetrate the body of the starfish and kill his chum.

"But the rubber suit ought to insulate and protect him," mused the young inventor. "Here goes!"

Taking quick aim, Tom pulled the switch, and the deadly charge shot out of the rifle toward the sea monster.



CHAPTER XVI

GASPING FOR AIR

For an instant after the electrical charge had been fired nothing seem to happen. The giant starfish still enveloped Ned Newton in its grip, while Tom and his two companions stood tensely waiting and those in the submarine looked anxiously out through the thick glass windows.

Then, as the powerful current made itself felt, those watching saw one of the arms slowly loosen its grip. Another floated upward, as a strand of rope idly drifts in the current. Tom saw this, and called through his telephone:

"He's feeling it! Go to him, boys! Koku, you with the axe!"

They needed no second urging.

Springing toward the monster, Koku with upraised axe and Norton with the lance, they attacked the starfish. Hacking and stabbing, they completed the work begun by Tom's electric gun. With one powerful stroke, even hampered as he was by the heavy medium in which he operated, Koku lopped off one of the legs. Norton thrust his lance deep into the body of the monster, but this was hardly needed, for the starfish was now dead, and gradually the remaining arms relaxed their hold.

Pushing with their weapons, the giant and the sailor now freed Ned from the bulk of the creature, which floated away. It was almost immediately attacked by a school of fish that seemed to have been waiting for just this chance. Ned Newton was freed, but for a moment he staggered about on the floor of the sea, hardly able to stand.

"Are you all right, Ned? Did he pierce your suit?" asked Tom, anxiously through the telephone.

"Yes, I'm all right," came back the reassuring answer. "I'm a bit cramped from the way he held me, but that's all. Guess he found this suit of rubber and steel too much for his digestion."

Slowly, for Ned was indeed a bit stiff and cramped, they made their way back to the submarine, passing through a vast horde of small fishes which had been attracted by the dismemberment of the monster that had been killed.

"There'll be sharks along soon," said Tom to Ned through the telephone. "They're not going to miss such a gathering of food as these small fry present. And sharks will present a different emergency from starfish."

Tom spoke truly, for a little later, when they were all once more safely within the submarine, looking through the windows, they saw a school of hungry sharks feeding on the millions of small fish that gathered to eat the creature that had attacked Ned.

"What did you think was happening to you out there?" asked Tom, when the diving suits had been put away.

"I didn't know what to think," was the answer. "I was prospecting around, and I leaned over to pick up a particularly beautiful bit of coral. All at once I felt something over me, as a cloud sometimes hides the sun. I looked up, saw a big black shape settling down, and then I felt my arms pinned to my sides. At first I thought it was an octopus, but in a moment I realized what it was. Though I never thought before that starfish grew so large."

"Nor I," added Tom. "Well, you've had an experience, to say the least."

They remained a little longer in the vicinity, Tom and his officers making observations they thought would be useful to them later, and then the submarine went up to the surface.

They cruised in the open the rest of that day, recharging the storage batteries and getting ready for the search which, Tom calculated, would take them some time. As he had explained, it would not be easy to locate the Pandora in the fathomless depths of the sea.

Ned and Mr. Damon did some fishing while they were on the surface, and, as their luck was good, there was a welcome change from the usual food of the M. N. 1. Though, as Tom had installed a refrigerating plant, fresh meat could be kept for some time, and this, in addition to the tinned and preserved foods, gave them an ample larder.

"When are we going to begin the real search for the gold?" asked Mr. Hardley that evening.

"I should say in another day or two," Tom answered, after he had consulted the charts and made calculations of their progress since leaving their dock. "We shall then be in the vicinity of the place where you say the Pandora went down, and, if you are sure of your location, we ought to be able to come approximately near to the location of the gold wreck."

"Of course I am sure of my figures," declared Mr. Hardley. "I had them directly from the first mate, who gave them to the captain."

"Well, it remains to be seen," replied Tom Swift. "We'll know in a few days."

"And I hope there will be no more taking chances," went on the gold-seeker. "I don't see any sense in you people going out in diving suits to fight starfish. We need those suits to recover the gold with, and it's foolish to take needless risks."

His tone and manner were dictatorial, but Tom said nothing. Only when he and Mr. Damon were alone a little later the eccentric man said:

"Tom will you ever forgive me for introducing you to such a pest?"

"Oh, well, you didn't know what he was," said Tom good-naturedly. "You're as badly taken in as I am. Once we get the gold and give him his share, he can get off my boat. I'll have nothing more to do with him!"

Not wishing to navigate in the darkness, for fear of not being able to keep an accurate record of the course and the distance made Tom submerged the craft when night came and let her come to rest on the bottom of the sea. He calculated that two days later they would be in the vicinity of the Pandora.

The night passed without incident, situated, as they were, on the sand about three hundred feet below the surface; and after breakfast Tom announced that they would go up and head directly for the place where the Pandora had foundered.

The ballast tanks were emptied, the rising rudder set, and the M. N. 1 began to ascend. She was still several fathoms from the surface when all on board became aware of a violent pitching and tossing motion.

"Bless my postage stamp, Tom!" exclaimed Mr. Damon, "what's the matter now?"

"Has anything gone wrong?" demanded Mr. Hardley.

"Nothing, except that we are coming up into a storm," answered the young inventor. "The wind is blowing hard up above and the waves are high. The swell makes itself felt even down here."

Tom's explanation of the cause of the pitching and rolling of the submarine proved correct. When they reached the surface and an observation was taken from the conning tower, it was seen that a terrific storm was raging. It was out of the question to open the hatches, or the M. N. 1 would have been swamped. The waves were high, it was raining hard and the wind blowing a hurricane.

"Well, here's where we demonstrate the advantage of traveling in a submarine," announced Tom, when it was seen that journeying on the surface was out of the question. "The disturbance does not go far below the top. We'll submerge and be in quiet waters."

He gave the orders, and soon the craft was sinking again. The deeper she went the more untroubled the sea became, until, when half way to the bottom, there was no vestige of the storm.

"Are we going to lie here on the bottom all day, or make some progress toward our destination?" asked the gold-seeker, when Tom came into the main cabin after a visit to the engine room. "It seems to me," went on Mr. Hardley, "that we've wasted enough time! I'd like to get to the wreck, and begin taking out the gold."

"That is my plan," said Tom quietly. "We will proceed presently—just as soon as navigating calculations can be made and checked up. If we travel under water we want to go in the right direction."

His manner toward the gold-seeker was cool and distant. It was easy to see that relations were strained. But Tom would fulfill his part of the contract.

A little later, after having floated quietly for half an hour or so, the craft was put in motion, traveling under water by means of her electric motors. All that day she surged on through the salty sea, no more disturbed by the storm above than was some mollusk on the sandy bottom.

It was toward evening, as they could tell by the clocks and not by any change in daylight or darkness, that, as the submarine traveled on, there came a sudden violent concussion.

"What's that?" cried Mr. Damon.

"We've struck something!" replied Tom, who was with the others in the cabin, the navigation of the craft having been entrusted to one of the officers. "Keep cool, there's no danger!"

"Perhaps we have struck the wreck!" exclaimed Mr. Hardley.

"We aren't near her," answered the young inventor. "But it may be some other half-submerged derelict. I'll go to see, and—"

Tom's words were choked off by a sudden swirl of the craft. She seemed about to turn completely over, and then, twisted to an uncomfortable angle, so that those within her slid to the side walls of the cabin, the M. N. 1 came to an abrupt stop. At the same time she seemed to vibrate and tremble as if in terror of some unknown fate.

"Something has gone wrong!" exclaimed Tom, and he hurried to the engine room, walking, as best he could with the craft at that grotesque angle. The others followed him.

"What's the matter, Earle?" asked Tom of his chief assistant.

"One of the rudders has broken, sir," was the answer. "It's thrown us off our even keel. I'll start the gyroscope, and that ought to stabilize us."

"The gyroscope!" cried Tom. "I didn't bring it. I didn't think we'd need it!"

For a moment Earle looked at his commander. Then he said:

"Well, perhaps we can make a shift if we can repair the broken rudder. We must have struck a powerful cross current, or maybe a whirlpool, that tore the main rudder loose. We've rammed a sand bank, or stuck her nose into the bottom in some shallow place, I'm afraid. We can't go ahead or back up."

"Do you mean we're stuck, as we were in the mud bank?" asked Mr. Hardley.

"Yes," answered Tom, and Earle nodded to confirm that version of it.

"But we'll get out!" declared Tom. "This is only a slight accident. It doesn't amount to anything, though I'm sorry now I didn't take my father's advice and bring the gyroscope rudder along. It would have acted automatically to have prevented this. Now, Mr. Earle, we'll see what's to be done."

All night long they worked, but when morning came, as told by the clocks, they were still in jeopardy.

And then a new peril confronted them!

Earle, coming from the crew's quarters, spoke to Tom quietly in the main cabin.

"We'll have to turn on one of the auxiliary air tanks," he said. "We've consumed more than the usual amount on account of the men working so hard, and we used one of the compressed air motors to aid the electrics. We'll have to open up the reserve tank."

"Very well, do so," ordered Tom.

But a grim look came to his face when Earle, returning a little later, reported with blanched cheeks:

"The extra tank hasn't an atom of air in it, sir!"

"What do you mean?" asked Tom, in fear and alarm.

"I mean that the valve has been opened in some way—broken perhaps by accident—and all the air we have is what's in the submarine now. Not an atom in reserve, sir!"

"Whew!" whistled Tom, and then he stood up and began breathing quickly.

Already the atmosphere was beginning to be tainted, as it always becomes in a closed place when no fresh oxygen can enter. Without more fresh air the lives of all in the submarine were in imminent peril. And even as Tom listened to the report of his officer, he and the others began gasping for breath.



CHAPTER XVII

WHERE IS IT?

"Down on your faces!" called Tom to those with him in the cabin. "Lie down, every one! The freshest air is near the floor; the bad air rises, being lighter with carbonic acid. Lie down!"

All obeyed, Tom following the advice he himself gave. It was a little easier to breathe, lying on the tilted cabin floor, but how long could this be kept up? That was a question each one asked himself.

"Is every bit of our reserve air used?" asked Tom, speaking to Earle.

"As far as I can learn, yes, sir. If I had known that the auxiliary tank was empty I wouldn't have ordered the compressed air motor used. But I didn't know."

"No one is to blame," said Tom in a low voice. "It is one of the accidents that could not be foreseen. If there is any blame it attaches to me for not installing the gyroscope rudder. If we had had that when we were caught in the cross current, or the whirlpool swirl, our equilibrium would have been automatically maintained. As it is—"

He did not finish, but they all knew what he meant.

"Bless my soda fountain, Tom!" murmured Mr. Damon, "but isn't there any way of getting fresh air?"

"None without rising to the top," Tom answered. "We'll have to try that. Come with me to the engine room, Mr. Earle. It may be possible we can pull her loose."

They started to crawl on their hands and knees, to take advantage of the purer air at the floor level. The situation of the M. N. 1 was exactly the same as it had been when she ran into the mud bank in the river, with the exception that now she was in graver danger, for the supply of air for breathing was almost exhausted.

Reaching the engine room, where he found the crew lying down to take advantage of the better air near the floor, Tom made a hasty examination of the apparatus. There was still plenty of power left in the storage batteries, but, so far, the motors they operated had not been able to pull the craft loose from where her nose was stuck fast.

"Are the tanks completely emptied?" asked Tom.

"As nearly so as we could manage with the pumps not acting to their full capacity," answered Earle. "If we could turn the craft on a more level keel we might empty them further, and then her natural buoyancy would send her up."

"Then that's the thing to try to do!" exclaimed Tom, his head beginning to feel the heaviness due to the impure air. "We'll move every stationary object over to the port side, and we'll all stand there, or lie there, ourselves. That may heel her over, and help loosen the grip of the sand."

"It's worth trying," said Earle. "Get ready, men!" he called to the crew.

Tom crawled back to the main cabin and told Mr. Damon and the others what was to be attempted.

"Koku, you come and help move things," requested Tom.

"Me move anything!" boasted the giant, who, because of his great strength and reserve power did not seem as greatly affected as were the others.

Going back to the engine room with Koku, Tom assisted, as well as he could, in the shifting of pieces of apparatus, stores and other things that were movable. They all worked at a great disadvantage except Koku, and he did not seem to feel the lack of vitalizing air.

One thing after another was shifted, and still the M. N. 1 maintained the dangerous angle.

"It isn't going to work!" gasped Tom, as he noticed the indicator which told to what angle the craft was still off an even keel. "We'll have to try something else."

"Is there anything to try?" asked Earle, in a faint voice. He was on the point of fainting for lack of air.

Tom looked desperately around. There was one piece of heavy machinery that might be moved to the other side of the engine room. It was bolted to the floor, but its added weight, with that of the crew and passengers, together with what had already been shifted, might turn the trick.

"Let's try to move that!" said Tom faintly, pointing to it.

"It will take an hour to unbolt it," said one of the men.

"Koku!" gasped Tom, pointing to the heavy apparatus. "See if—see if you—"

Tom's breath failed him, and he sank down in a heap. But he had managed to make the giant understand what was wanted.

"Koku do!" murmured the big man. Striding to the piece of machinery, the legs of which were bolted to the floor, Koku got his arms under it. Bending over, and arching his back, so as to take full advantage of his enormous muscles, the giant strained upward.

There was a cracking of bone and sinew, a rasping sound, but the machinery did not leave the floor.

"Him must come!" gasped the giant. "One more go!"

He took a hold lower down. Tom's eyes were dim now, and he could not see well. Some of the men were unconscious.

Then, suddenly, there was a loud, breaking sound, and something tinkled on the steel floor of the submarine engine room. It was the heads of the bolts which Koku had torn loose. Like hail they fell about the giant, and in another instant the big man had pulled loose the machine, weighing several hundreds of pounds. In another moment he shoved it across the floor, toward the elevated side of the craft.

For a second or two nothing happened. Then slowly, very slowly, the M. N. 1 began to heel over.

"She's turning!" some one gasped.

An instant later, freed by this turning motion from the grip of the sand bank, the submarine shot to the surface. Up and up she went, breaking out on the open sea as a great fish darts upward from the hidden depths.

It was the work of only a few seconds for the man nearest it to open the hatch, and then in rushed the life-giving air. Tom and his companions were saved, and by Koku's strength.

"Me say him machine got to come up—him come up!" said the giant, smiling in happy fashion, when, after they had all gulped down great mouthfuls of the precious oxygen, they were talking of their experience.

"Yes, you certainly did it," said Tom, and due credit was given to Koku.

"Never again will I travel without a gyroscope," declared Tom. "I'm almost ready to go back and have one installed now."

"No, don't!" exclaimed the gold-seeker. "We are almost at the place of the wreck."

"Well, I suppose we can travel more slowly and not run a risk like that again," decided Tom. "I'll put double valves on the emergency air tank, so no accident will release our supply again."

This was done, after the broken valves had been repaired, and then, when the machine Koku had torn loose was fastened down again, and the submarine restored to her former condition, a consultation was held as to what the next step should be.

They were in the neighborhood of the West Indies, and another day, or perhaps less, of travel would bring them approximately to the place where the Pandora had foundered. The latitude and longitude had been computed, and then, with air tanks filled, with batteries fully charged, and everything possible done to insure success, the craft was sent on the last leg of her journey.

For two days they made progress, sometimes on the surface, and again submerged, and, finally, on the second noon, when the sun had been "shot," Tom said:

"Well, we're here!"

"You mean at the place of the wreck?" asked Mr. Hardley.

"At the place where you say it was," corrected Tom.

"Well, if this is the place of which I gave you the longitude and latitude, then it's down below here, somewhere," and the gold-seeker pointed to the surface of the sea. It was a calm day and the ocean was the proverbial mill pond.

"Let's go down and try our luck," suggested Tom.

The orders were given, the tanks filled, the rudders set, and, with hatches closed, the M. N. 1 submerged. Then, with the powerful searchlight aglow, the search was begun. Moving along only a few feet above the floor of the ocean, those in the submarine peered from the glass windows for a sight of the sunken Pandora.

All the rest of that day they cruised about below the surface. Then they moved in ever widening circles. Evening came, and the wreck had not been found. The search was kept up all night, since darkness and daylight were alike to those in the undersea craft.

But when three days had passed and the Pandora had not been seen, nor any signs of her, there was a feeling of something like dismay.

"Where is it?" demanded Mr. Hardley. "I don't see why we haven't found it! Where is that wreck?" and he looked sharply at Tom Swift.



CHAPTER XVIII

A SEPARATION

"Mr. Hardley," began Tom calmly, as he took a seat in the main cabin, "when we started this search I told you that hunting for something on the bottom of the sea was not like locating a building at the intersection of two streets."

"Well, what if you did?" snapped the gold-seeker. "You're supposed to do the navigating, not I! You said if I gave you the latitude and longitude, down to seconds, as well as degrees and minutes, which I have done, that you could bring your submarine to that exact point."

"I said that, and I have done it," declared Tom. "When we computed our position the other day we were at the exact location you gave me as being the spot where the Pandora foundered."

"Then why isn't she here?" demanded the unpleasant adventurer. "We went down to the bottom at the exact spot, and we've been cruising around it ever since, but there isn't a sign of the wreck. Why is it?"

"I'm trying to explain," replied Tom, endeavoring to keep his temper. "As I said, finding a place on the open sea is not like going to the intersection of two streets. There everything is in plain sight. But here our vision is limited, even with my big searchlight. And being a few feet out of the way, as one is bound to be in making nautical calculations, makes a lot of difference. We may have been close to the wreck, but may have missed it by a few yards."

"Then what's to be done?" asked Mr. Hardley.

"Keep on searching," Tom answered. "We have plenty of food and supplies. I came out equipped for a long voyage, and I'm not discouraged yet. Another thing. The ship may have moved on several fathoms, or even a mile or two, after her last position was taken before she went down. In that case she'd be all the harder to find. And even granting that she sank where you think she did, the ocean currents since then may have shifted her. Or she may be covered by sand."

"Covered by sand!" exclaimed the gold-seeker.

"Yes," replied Tom. "The bottom of the ocean is always changing and shifting. Storms produce changes in currents, and currents wash the sand on the bottom in different directions. So that a wreck which may have been exposed at one time may be covered a day or so later. We'll have to keep on searching. I'm not ready to give up."

"Maybe not. But I am!" snapped out Mr. Hardley.

"What do you mean?" asked the young inventor.

"Just what I said," was the quick answer. "I'm not going to stay down here, cruising about without knowing where I'm going. It looks to me as if you were hunting for a needle in a haystack."

"That's just about what we are doing," and Tom tried to speak good-naturedly.

"Then do you know what I think?" the gold-seeker fairly shot forth.

"Not exactly," Tom replied.

"I think that you don't understand your business, Swift!" was the instant retort. "You pretend to be a navigator, or have men who are, and yet when I give you simple and explicit directions for finding a sunken wreck you can't do it, and you cruise all around looking for it like a dog that has lost the scent! You don't know your business, in my estimation!"

"Well, you are entitled to your opinion, of course," agreed Tom, and both Mr. Damon and Ned were surprised to see him so calm. "I admit we haven't found the wreck, and may not, for some time."

"Then why don't you admit you're incompetent?" cried Mr. Hardley.

"I don't see why I should," said Tom, still keeping calm. "But since you feel that way about it, I think the best thing for us to do is to separate."

"What do you mean?" stormed the other.

"I mean that I will set you ashore at the nearest place, and that all arrangements between us are at an end."

"All right then! Do it! Do it!" cried Mr. Hardley, shaking his fist, but at no one in particular. "I'm through with you! But this is your own decision. You broke the contract—I didn't, and I'll not pay a cent toward the expenses of this trip, Swift! Mark my words! I won't pay a cent! I'll claim the money I deposited in the bank, and I won't pay a cent!"

"I'm not asking you to!" returned Tom, with a smile that showed how he had himself in command. "You put up a bond, secured by a deposit, to insure your share of the expenses—yours and Mr. Damon's. Very well, we'll consider that bond canceled. I won't charge you a cent for this trip. But, mark this, Hardley: What I find from now on, is my own! You don't share in it!"

"You mean that—"

"I mean that if I discover the wreck of the Pandora and take the gold from her, that it is all my own. I will share it with Mr. Damon, provided he remains with me—"

"Bless my silk hat, Tom, of course I'll stay with you!" broke in the eccentric man.

"But you don't share with me," went on the young inventor, looking sternly at the gold-seeker. "What I find is my own!"

"All right—have it that way!" snapped the adventurer. "Set me ashore as soon as you can—the sooner the better. I'm sick of the way you do business!"

"Nothing like being honest!" murmured Ned. But, as a matter of fact, he was glad the separation had come. There had been a strain ever since Hardley came aboard. Mr. Damon, too, looked relieved, though a trifle worried. He had considerable at stake, and he stood to lose the money he had invested with Dixwell Hardley.

"This is final," announced Tom. "If we separate we separate for good, and I'm on my own. And I warn you I'll do my best to discover that wreck, and I'll keep what I find."

"Much good may it do you!" sneered the other. "Perhaps two can play that game."

No one paid much attention to his words then, but later they were recalled with significance.

"Get ready to go up!" Tom called the order to the engine room.

"Where are you going to land me?" asked Mr. Hardley. "I have a right to know that?"

"Yes," conceded Tom, "you have. I'll tell you in a moment."

He consulted a chart, made a few calculations and then spoke.

"I shall land you at St. Thomas," answered the young inventor. "I do not wish to bring my submarine to a place that is too public, as too many questions may be asked. From St. Thomas you can easily reach Porto Rico, and from there you can go anywhere you wish."

"Very well," murmured the malcontent. "But I don't consider that I owe you a cent, and I'm not going to pay you."

"I wouldn't take your money," Tom answered. "And don't forget what I said—that what I find is my own."

The other answered nothing. Nor from then on did he hold much conversation with Tom or any others in the party. He kept to himself, and a day later he was landed, at night, at a dock, and if he said "good-bye" or wished Tom and his friends a safe voyage, they did not hear him.

They were steaming along on the surface the next day, and at noon the submarine suddenly halted.

"What's on now, Tom?" asked Ned, as he saw his chum prepare to go up on deck with some of the craft's officers.

"We're going to 'shoot the sun' again," was the answer. "I want to make sure that we were right in our former calculations as to the position of the Pandora. The least error would throw us off."

Using the sextant and other apparatus, some of which Tom had invented himself, the exact position of the submarine was calculated. As the last figure was set down and compared with their previous location, one of the men who had been doing the computing gave an exclamation.

"What's the matter?" asked Tom.

"Look!" was the answer, and he pointed to the paper. "There's where a mistake was made before. We were at least two miles off our course."

"You don't say so!" exclaimed Tom, and, taking the sheet, he went rapidly over the results.



CHAPTER XIX

THE SERPENT WEED

All waited eagerly for Tom Swift to verify the statement of the other mathematician, and the young inventor was not long in doing this, for he had what is commonly known as a "good head for figures."

"Yes, I see the mistake," said Tom. "The wrong logarithm was taken, and of course that threw out all the calculations. I should say we were nearer three miles off our supposed location than two miles."

"Does that mean," asked Mr. Damon, "that we began a search for the wreck of the Pandora three miles from the place Hardley told us she was."

"That's about it," Tom said. "No wonder we couldn't find her."

"What are you going to do?" Ned wanted to know.

"Get to the right spot as soon as possible and begin the search there," Tom answered. "You see, before we submerged as nearly as possible at the place where we thought the Pandora might be on the ocean bottom. From there we began making circles under the sea, enlarging the diameter each circuit.

"That didn't bring us anywhere, as you all know. Now we will start our series of circles with a different point as the center. It will bring us over an entirely different territory of the ocean floor."

"Just a moment," said Ned, as the conference was about to break up. "Is it possible, Tom, that in our first circling that we covered any of the ground which we may cover now? I mean will the new circles we propose making coincide at any place with the previous ones?"

"They won't exactly coincide," answered the young inventor. "You can't make circles coincide unless you use the same center and the same radius each time. But the two series of circles will intersect at certain places."

"I guess intersect is the word I wanted," admitted Ned.

"What's the idea?" Tom wanted to know.

"I'm thinking of Hardley," answered his chum. "He might assert that we purposely went to the wrong location with him to begin the search, and if we afterward find the wreck and the gold, he may claim a share."

"Not much he won't!" cried Tom.

"Bless my check book, I should say not!" exclaimed Mr. Damon.

"Hardley broke off relations with us of his own volition," said Tom. "He 'breached the contract,' as the lawyers say. It was his own doing.

"He has put me to considerable expense and trouble, not to say danger. He was aware of that, and yet he refused to pay his share. He accused me of incompetence. Very well. That presuggested that I must have made an error, and it was on that assumption that he said I did not know my business. Instead of giving me a chance to correct the error, which he declared I had made, he quit—cold. Now he is entitled to no further consideration.

"An error was made—there's no question of that. We are going to correct it, and we may find the gold. If we do I shall feel I have a legal and moral right to take all of it I can get. Mr. Hardley, to use a comprehensive, but perhaps not very elegant expression, may go fish for his share."

"That's right!" asserted Mr. Damon.

"I guess you're right, Tom," declared Ned. "There's only one more thing to be considered."

"What's that?" asked the young inventor.

"Why, Hardley himself may find out in some way that we were barking up the wrong tree, so to speak. That is, learn we started at the wrong nautical point. He may get up another expedition to come and search for the gold and—"

"Well, he has that right and privilege," said Tom coolly. "But I don't believe he will. Anyhow, if he does, we have the same chance, and a better one than he has. We're right here, almost on the ground, you might say, or we shall be in half an hour. Then we'll begin our search. If he beats us to it, that can't be helped, and we'll be as fair to him as he was to us. This treasure, as I understand it, is available to whoever first finds it, now that the real owners, whoever they were, have given it up."

"I guess you're right there," said Mr. Damon. "I'm no sea lawyer, but I believe that in this case finding is keeping."

"And there isn't one chance in a hundred that Hardley can get another submarine here to start the search," went on Tom. "Of course it's possible, but not very probable."

"He might get an ordinary diving outfit and try," Ned suggested.

"Not many ordinary divers would take a chance going down in the open sea to the depth the Pandora is supposed to lie," Tom said. "But, with all that, we have the advantage of being on the ground, and I'm going to make use of that advantage right away."

He gave orders at once for the M. N. 1 to proceed, and this she did on the surface. It was decided to steam along on the open sea until the exact nautical position desired was reached. This position was the same Mr. Hardley had indicated, but that position was not before attained, owing to an error in the calculations.

As all know, to get to a certain point on the surface of the ocean, where there is no land to give location, a navigator has to depend on mathematical calculations. The earth's surface is divided by imaginary lines. The lines drawn from the north to the south poles are called meridians of longitude. They are marked in degrees, and indicate distance east or west of the meridian of, say, Greenwich, England, which is taken as one of the centers. The degrees are further divided into minutes and seconds, each minute being a sixtieth of a degree and each second, naturally, the sixtieth of a minute.

Now, if a navigator had to depend only on the meridian lines indicating distance east and west, he might be almost any distance north or south of where he wanted to go. So the earth is further divided into sections by other imaginary lines called parallels of latitude. As all know, these indicate the distance north or south of the middle line, or the equator. The equator goes around the earth at the middle, so to speak, running from east to west, or from west to east, according as it is looked at. The meridian of Greenwich may be regarded as a sort of half equator, running half way around the earth in exactly the opposite direction, or from north to south.

The place where any two of these imaginary lines, crossing at right angles, meet may be exactly determined by the science of navigation. It is a complicated and difficult science, but by calculating the distance of the sun above the horizon, sometimes by views of stars, by knowing the speed of the ship, and by having the exact astronomical time at hand, shown on an accurate chronometer, the exact position of a ship at any hour may be determined.

By this means, if a navigator wants to get to a place where two certain lines cross, indicating an exact spot in the ocean, he is able to do so. He can tell for instance when he has reached the place where the seventy-second degree of longitude, west from Greenwich, meets and crossed the twentieth parallel of latitude. This spot is just off the northern coast of Haiti. Other positions are likewise determined.

It was after about an hour of rather slow progress on the surface of the calm sea, no excess speed being used for fear of over-running the mark, that Tom and his associates gathered on deck again to make another calculation.

Long and carefully they worked out their position, and when, at last, the figures had been checked and checked again, to obviate the chance of another error, the young inventor exclaimed:

"Well, we're here!"

"Really?" cried Ned.

"No doubt of it," said his chum.

"Bless my doormat!" cried Mr. Damon. "And do you mean to say, Tom Swift, that if we submerge now we'll be exactly where the Pandora lies, a wreck on the floor of the ocean.

"I mean to say that we're at exactly the spot Where Hardley said she went down," corrected Tom, "and we weren't there before—that is not so that we actually knew it. Now we are, and we're going down. But that doesn't guarantee that we'll find the wreck. She may have shifted, or be covered with sand. All that I said before in reference to the difficulty in locating something under the surface of the sea still holds good."

Once more, to make very certain there was no error, the figures were gone over, Then, as one result checked the other, Tom put away the papers, the nautical almanac, and said:

"Let's go!"

Slowly the tanks of the M. N. 1 began to fill. It was decided to let her sink straight down, instead of descending by means of the vertical rudders. In that way it was hoped to land her as nearly as possible on the exact spot where the Pandora was supposed to be.

"How deep will it be, Tom?" asked Ned, as he stood beside his chum in the forward observation cabin and watched the needle of the gauge move higher and higher.

"About six hundred feet, I judge, going by the character of the sea bottom around here. Certainly not more than eight hundred I should say." And Tom was right. At seven hundred and eighty-six feet the gauge stopped moving, and a slight jar told all on board that the submarine was again on the ocean floor.

"Now to look for the wreck!" exclaimed Tom. "And it will be a real search this time. We know we are starting right."

"Are you going to put on diving suits and walk around looking for her?" asked Ned.

"No, that would take too long," answered Tom. "We'll just cruise about, beginning with small circles and gradually enlarging them, spiral fashion. We'll have to go up a few feet to get off the bottom."

As Tom was about to give this order Ned looked from the glass windows. The powerful searchlight had been switched on and its gleams illuminated the ocean in the immediate vicinity of the craft.

As was generally the case, the light attracted hundreds of fish of various shapes, sizes, and, since the waters were tropical, beautiful colors. They swarmed in front of the glass windows, and Ned was glad to note that there were no large sea creatures, like horse mackerel or big sharks. Somehow or other, Ned had a horror of big fish. There were sharks in the warm waters, he well knew, but he hoped they would keep away, even though he did not have to encounter any in the diving suit.

Slowly the submarine began to move. And as she was being elevated slightly above the ocean bed, to enable her to proceed, Ned uttered an exclamation and pointed to the windows.

"Look, Tom!" he cried.

"What is it?" the young inventor asked.

"Snakes!" whispered his chum. "Millions of 'em! Out there in the water! Look how they're writhing about!"

Tom Swift laughed.

"Those aren't snakes!" he said. "That's serpent grass—a form of very long seaweed which grows on certain bottoms. It attains a length of fifty feet sometimes, and the serpent weed looks a good deal like a nest of snakes. That's how it got its name. I didn't know there was any here. But we must have dropped down into a bed of it."

"Any danger?" asked Ned.

"Not that I know of, only it may make it more difficult for us to see the wreck of the Pandora."

As Tom turned to leave the cabin the submarine suddenly ceased moving. And she came to a gradual stop as though she had been "snubbed" by a mooring line.

"I wonder what's the matter!" exclaimed Tom. "We can't have come upon the wreck so soon."

At that moment a man entered the cabin.

"Trouble, Mr. Swift!" he reported.

"What kind?" asked Tom.

"Our propellers are tangled with a mass of serpent weed," was the answer. "They're both fouled, and we can't budge."

"Bless my anchor chain!" ejaculated Mr. Damon. "Stuck again!"



CHAPTER XX

THE DEVIL FISH

It was true. The long sinuous strands of ocean grass, known under the name of "serpent weed," had caught around the whirling propellers and there had been wound and twisted very tightly. Just as sometimes the stern line gets so tightly twisted around a motor boat propeller as to require hours of work with an axe to free it, the seaweed was twisted around the blades of the M. N. 1.

Slowly the undersea craft came to a stop, and there she remained, floating freely enough, but a few feet above the bottom of the ocean. There was a look of alarm on the faces of Ned and Mr. Damon, but Tom Swift smiled.