"Oh I wasn't 'fraid," spoke up Washington. "I were jest 'stonished, dat's all."

"What did you get down on your knees for?" asked Mark with a grin.

"I might hab been lookin' for my collar button, for all you knows," replied Washington, with an air of great dignity, and went back to the engine room.

For several days after this the Porpoise continued on her way south. Now and then appearing on the surface to renew the supply of fresh air, and again skimming along under the surface, or deep down, the strange craft kept on. It grew much warmer, and even when some distance below the surface the heat could be felt in an uncomfortable manner.

"We're getting near the equator," explained the professor.

One afternoon, when dinner had just been finished, and the ship, under the direction of Washington, was gliding along well under the sea, there came a sudden shock.

"We've hit something!" exclaimed Mr. Henderson as he jumped for the conning tower. The shock was repeated.

"What was it?" asked someone.

"Shut down the engine!" yelled the inventor to the colored man. "What do you want to go on ramming an object after you've once hit it? Slow down the engine!"

"Power's shut off!" cried Washington. "We didn't hit nothin'! Something hit us!"

"What do you mean?" asked Mr. Henderson.

"Somethin's rammin' us," went on Washington.

"It must be a big monster. I was sterrin' along an' there was nothin' in de road, when all of a suddint, ker-plunk! We's hit. Look ahead, an' you can't see nothin'!"

The professor, and the boys, who had followed him, gazed out of the conning tower window. There was nothing forward but a vast expanse of water.

The next instant the ship careened as something struck her a violent blow on the port side. Everyone almost toppled over from the force of the impact.

"Dar he goes agin!" cried Washington.

"We're attacked by a whale!" said the professor. "We must rise to the surface or it may damage the ship."

"If it's a whale I'd like to get a shot at it," put in Andy Sudds, from the foot of the companion ladder leading into the tower.

"I don't know that it is a whale," went on the inventor. "But it must be something very big and strong."

"It's a monster of some sort," put in Andy, "and I want a chance at him."

"It's too risky," murmured the professor. "We couldn't get down to bottom here, as the water is several miles deep, and the pressure would crush the Porpoise, strong as she is."

Once more came a terrible blow and the ship rocked in a swirl of foam beneath the waves. In quick succession two more fierce onslaughts were made by the unseen monster.

"We'll have to do something," muttered Andy.

"You're right," agreed the professor. "Our only chance is to rise to the surface, for I do not believe the creature will follow us there. Empty the tanks, Washington."

The colored man started the pumps, and the professor watched the gages that told the depth of the craft. The pointer should have begun to swing around in a few seconds after the tanks began to empty. Instead it remained stationary.

"Strange," said Mr. Henderson. "I wonder if anything is wrong with the machinery."

"More like the whale, or whatever it is, is on top of the boat, holding her down," suggested Andy.

There was no doubt of this a moment later, for there were several violent blows on the upper part of the Porpoise.

The crew of the submarine were held prisoners below the surface by the unknown monster!

For a few minutes the thought of the awful fate that would be theirs if the ship should be wrecked under the water made each one speechless. As they stood looking at each other, not knowing what to do, the attack was renewed on the port side.

The big fish, whale or whatever it was, kept pounding away.

"I have an idea!" cried Andy suddenly.

"What is it?" asked the professor quickly.

"Let me put a diving dress on," began the old hunter.

"I tell you we can't sink to the bottom in this depth of water," interrupted the professor.

"We don't need to," put in Andy. "All I want is a diving suit and a chance to stand out in the diving chamber. I guess I can fix Mr. Whale, if I have one of those electric guns."

"Quick! Get a diving suit, Washington!" cried Mr. Henderson. He saw what the old hunter planned to do.

In a few minutes Andy was dressed in the suit. The attacks of the monster had redoubled in frequency, and the ship rocked as in a storm.

Andy stepped into the diving chamber, clasping the electric gun. The inner door was tightly closed and then the sea cocks that admitted water from the outside were opened. When the pressure inside the chamber was equal to that of the ocean outside some one pulled the lever that opened the outer door.

Andy knew better than to step outside. He remained in the chamber, like a sentinel hid in the embrasure of a wall, for the chamber was a sort of big dent in the side of the Porpoise.

Once more the ship rocked from a terrific blow, and the old hunter was nearly thrown out and into the fathomless depths below.

He clung to the door lever and peered out. Through the big glass eyes of his copper helmet he saw headed straight at him a whale that seemed larger than the submarine.



CHAPTER XI

CAUGHT IN A SEA OF GRASS

"It's all up with me and the ship, too," thought Andy as he stood in the small chamber and watched the oncoming of the monster.

However, he was not going to die without a fight, so he raised the electric gun. Yet he knew it was a most forlorn chance.

He aimed straight down the big open mouth and pulled the trigger. The next instant the water all about him was a mass of foam, through which he could dimly see that the whale had halted.

And, as the old hunter watched, in awe and fear at what he saw, he noted that instead of one monster there seemed to be a pair. Together they were threshing the sea into a bloody foam.

Then, turning on the searchlight in his helmet, Andy beheld a terrible sight. The whale had been attacked by a gigantic swordfish at the moment the hunter had fired the shot, and it was that, and not the electric bullet, that had stopped the infuriated animal's rush at the ship.

Ancient enemies, the whale and swordfish, had met in mortal combat. The swordfish had engaged the whale just as it was about to strike what would probably have been a blow that would have disabled the submarine, for with the door of the diving chamber open, the onslaught might not have been withstood.

Rushing here and there, the whale seeking to destroy his enemy with a sweep of the enormous flukes, and the swordfish plunging his bony weapon again and again into the whale, the two monsters fought until the water about the ship was a mass of foam and blood.

Much as he wanted to see the end of the fight, Andy knew it was dangerous to remain longer with the door open.

He closed it, pressed the lever which started the pumps, forcing the water from the chamber and, in a few minutes, emerged into the interior of the ship.

Mr. Henderson, realizing that something out of the ordinary was going on, had opened the slides of the bull's-eye windows, and those in the submarine saw part of the fight between the whale and swordfish.

As soon as Andy had removed his diving suit he advised that the ship be sent to the surface, as there might be danger should the monsters get too close in their struggles.

Accordingly the pumps, which had been stopped when it was found impossible to raise the ship, because of the weight of the whale, were started and the Porpoise was soon on the surface.

The manhole cover was opened and Andy, with Jack and Mark, went out on deck. They had no sooner stepped out on the platform than there was a commotion in the water.

"They're going to fight up here!" exclaimed Mark.

A big body shot upward and fell back with a splash, rocking the submarine.

"There's the whale," observed Andy. "But I reckon he won't fight any more. He's dead."

It was so. The swordfish had conquered, and the lifeless body of the whale floated on top of the water, only to sink a little later.

"It was a great battle," said Jack. "I'm glad I was inside the ship."

The course was due south, and every minute it seemed to the boys that it was getting warmer, for they were approaching the equator. Every hour brought them nearer the south pole, though they were still several thousand miles from it.

After a while quite a wind sprang up, and as the sea roughened the professor decided to go down under the surface. The Porpoise sunk as the tanks filled and, in a little while, the submarine was in calm water, and was forging ahead at three-quarter speed.

It was three days after the adventure with the whale when, as the ship was going along at a good rate, that there seemed to be a gradual slacking in the progress.

"I wonder what Washington is slowing down for," said the professor rising from the dinner table at which all save the colored man had been sitting. "I told him to keep right on. He must have seen something ahead. I'll take a look."

The inventor went to the conning tower, where Washington was steering.

"What are you stopping for?" he asked.

"I'm not slowin' down," replied the colored man. "Guess another ob dem debil fishes has grabbed holt ob de ship. Dey suttinly am de most koslostrous conglomerations ob inconsequence dat I eber see."

"You must keep your big words for another time," remarked Mr. Henderson, who seemed worried. "Hurry to the engine-room and see if the machinery is all right. We certainly are slowing down, from some cause or other."

The Porpoise was now scarcely moving, though from the vibration it was evident that the engines were working almost at top speed. Washington came back and reported that the big screw was revolving properly and that all the machinery was working well.

"Then we're caught in something," said the professor. "Shut off the power, Washington, I don't want to strain things."

The ship was now scarcely making a foot a minute, and, a little later, when the colored man had turned off the engine, the submarine became stationary, merely undulating with the roll and heave of the ocean.

Hurrying to the cabin, Captain Henderson opened the side window shutters, turned off the electric lights and peered out.

"I can't see anything," he said. "Yet I should be able to, as we are not very deep."

The gage showed that the ship was submerged only thirty feet, and at that depth there should have been no difficulty in seeing, at least dimly, objects under water. But the windows showed as black as night.

"Bring me one of the portable searchlights," called Mr. Henderson.

Washington brought one, operated by a storage battery. Holding it so the reflector cast the beams out of the bull's-eye and into the water on the opposite side, the inventor peered forth.

"I was afraid of this!" he murmured.

"What is it?" asked Jack.

"We are caught in the Sargasso Sea," replied Mr. Henderson.

"The Sargasso Sea?" repeated Mark, in a questioning tone. "What is that?"

"It is a great sea of grass," replied the captain. "An immense ocean of sea weed, that sometimes floats on the surface and sometimes a little below. The stalks or blades of the grass are very long and closely matted together."

"Is there any danger?" asked Andy in some alarm.

"Very much," answered the professor quietly. "A ship, once fairly entangled in the grass or sea weed, seldom gets out. If it is a sailing ship the weed clings to the rudder, making steerage impossible, and even in a strong wind the ship cannot get free of the mass. The grass winds about the propellers of steamships, and holds them as tight as in a vise.

"Sometimes a great storm may tear the mass of weed loose from the bottom of the ocean, and then the ship is free. But the Sargasso Sea is the graveyard of many a fine vessel."

The pumps were set going. Anxiously everyone watched the gage. The pointer never moved, but remained at thirty feet. The Porpoise was caught.

"Well, since we can't go up, let us see if we can go down," said the inventor. "Perhaps we can dive under the sea weed."

The cocks of the tanks were opened and the water rushed in. Under the weight of it the ship should have sunk to the bottom. Instead it remained just where it was, thirty feet below the surface.

"Try the screw again," suggested Andy, "Maybe we can back out."

The big propeller in the tube was started going in a reverse direction, but the Porpoise only moved a few feet and then stopped. To go forward was equally impossible.

The submarine was held fast in the grip of the long, sinuous, snake-like fingers of the terrible sea grass. Weak as one strand was, the thousands combined served to fasten the ship as securely as wire cables would have done. The weeds had entangled themselves all around the craft and refused to let go.

"Well," remarked Mr. Henderson when all efforts had failed. "We must think of a new plan."

He spoke cheerfully, for he did not want the boys and other members of the crew to know how worried he was. This was a danger he had never counted on when he planned to go to the south pole.

"There is no great hurry," Mr. Henderson went on in a few minutes. "We can stay here for several days if need be, and by that time a storm may tear the grass loose."

"If we had our old hay sythes here," spoke Bill, "me an' Tom could put on divin' suits an' go out an' cut the sea weed."

"I'm afraid that wouldn't work," answered Mr. Henderson. "I'll think up some plan, soon."

He started toward the engine room to look over the machinery. He was met by Washington, who seemed much alarmed.

"What's the matter?" asked the inventor.

"De air tank hab busted an' all de air is escapin' out!" cried the colored man. "We'll all smothercate!"



CHAPTER XII

FIRE ON BOARD

The professor jumped past Washington and hurried into the room where the tanks were kept, carrying the reserve supply of air for breathing when the ship was under water. A loud hissing told that the leak was a large one.

"Quick! Bring me some tools and a steel plug," shouted the captain.

Mark hurried in with the things the professor wanted. But before the plug could be put in the hole the air stopped hissing.

"The leak is fixed!" cried Jack.

"No," said the professor in a strange voice.

"But the air no longer rushes out."

"For a good reason, there is no longer any air to rush out. It is all gone!"

"Do you mean to say that all the reserve stock has been lost?" exclaimed Andy.

"I fear so. The leak must have been a bad one. The air was stored in tanks under pressure, and, as you know, we released it as we needed it. Now it is all gone."

"All? Then we shall smother," said Jack, and his voice trembled.

"Not at once," went on Mr. Henderson in a calm voice. "There is enough air in the entire ship, including that which has leaked from the tanks to last us five hours. After that——" he paused and looked at his watch.

"Well?" asked Andy. "After that?"

"There is enough stored in the small tanks of the diving suits to last another two hours, perhaps. Seven hours in all."

"Then what?" asked Mark.

"We shall smother to death," said the professor in a low tone. "That is," he went on, "unless before that time we can raise the Porpoise to the surface of the sea and get a fresh supply of air."

"Then we must work to raise the ship," put in Bill. "Let' get out and see if we can't cut through the sea weed."

"It would be useless," said Mr. Henderson. "We can only depend on the power of the ship herself. But do not be discouraged. We may escape. Come, Washington, start the engine again. By keeping it going constantly we can, perhaps, break loose from the grass. It is our only hope."

Steadily the machinery worked. It might as well have remained stationary, however, as far as any noticeable effect was made on the boat's progress. The grass of the Sargasso Sea held the Porpoise in a firm grasp.

Four hours passed. There was nothing to do but wait and see what would happen. It all depended on the engines. Silently the navigators of the realms under the ocean sat and hoped. Now and then the professor would go to the engine room to adjust the machines.

The atmosphere in the cabin was growing noticeably heavier. The boys' heads began to ring with strange noises, and there was a tightness across their chests. The lack of fresh air was beginning to tell.

"We might as well use that in the diving suit reservoirs," remarked the professor. "We will feel better, at least for a little while."

The helmets of the suits were brought in, and the vapor released from the small tanks. A change was at once noticed. The old stale air in the cabin was forced out of the exhaust pipes, and the fresh took its place. Every one felt better.

Faster and faster revolved the big screw. The ship vibrated more and more. Yet it did not move, nor did it rise. The crew were still prisoners beneath the water.

For an hour or so conditions were fairly comfortable. Then the same unpleasantness was experienced as was noticed before.

"If we could only open a window," sighed Mark, "and let in a lot of fresh air, how nice it would be."

The air rapidly became more foul. Soon Washington was gasping for breath. Tom and Bill showed signs of uneasiness.

"Lie down on the floor," counseled the professor. "You will find the air a little fresher down there."

They all did as he advised, the inventor himself stretching out at full length. A little relief was experienced.

They knew it could not last long. Even the professor seemed to have given up hope. The engine was not going to free the ship in time to save the lives of those on board.

Washington crawled to the engine room, as some of the bearings needed oiling. The professor seemed in despair. He opened one of the slides that covered the glass bulls eye windows. Then he turned off the electric lights. The opening was black, showing that the sea of grass still surrounded them. With a groan Mr. Henderson turned aside. The last hope was gone. He sank down on the floor of the darkened cabin.

Just then Mark happened to look at the bull's-eye. He saw a glimmer of light. Then he noticed several fishes swimming about. The water was clear. The grass had disappeared from the vicinity of the window.

"Look!" cried Mark to the professor.

The inventor peered forth. As he did so he uttered a cry. Then he staggered rather than ran to the engine room.

"What are you doing?" he called to Washington.

"I jest let some ob de sulphuric acid out ob de storage battery tank," replied the colored man.

"That's it! That's it!" exclaimed the professor. "Quick, let some more out, Washington. Let out all there is in that tank. It will save our lives."

Wonderingly Washington obeyed. The air in the ship was growing more foul every second. It was hard to breathe even on the floor, and all were gasping for breath. A few minutes more and they would all become unconscious and death would come in a little while if the air was not freshened.

The professor staggered back to the main cabin. He looked out of the bull's-eye windows. Then he exclaimed:

"See, it is getting lighter! Thank Heaven we are saved!"

The next instant the ship began to move backward. Then with increasing speed it pulled out of the grip of the long grass, and in another minute was floating on top of the water, at the edge of the Sargasso Sea.

"Quick! Open the man hole cover!" said Amos Henderson.

Washington threw back the lever cams, and in rushed the fresh air. It was a blessed relief from the terrible oppressiveness of the foul atmosphere of the boat. They all breathed deeply, and, in a few minutes the effects of their long imprisonment had passed off.

They went out on the small deck. It was getting dusk, and the reflection of the red sunset shone brightly on the heaving water.

"I 'spected I'd neber see dis again," said Washington. "Thought suah I was a gone chicken!"

"We had a most fortunate escape," said the professor. "You did the trick for us when you let the acid run from that tank into the sea. It mingled with the water and burned or ate through the stems of the grass so they no longer held the ship. I saw what had happened as soon as I looked out of the bull's-eye, and that's why I had you turn out all the acid you could. It was just as if liquid fire had touched the sea weed and burnt it off."

"Golly!" exclaimed Washington. "Fust I know I'll be a perfessor myself!"

Supper was eaten with the ship on the surface of the ocean, for it was impossible to go below until the leak in the air tanks had been repaired. Work was begun on this the next day, and though it proved a difficult job it was accomplished by Mr. Henderson and the boys.

There were several minor repairs to be made to the machinery, and it was a week before all was in readiness for another descent beneath the waves. In the meanwhile the craft had moved slowly southward on the surface, where no very great speed was possible.

Toward evening, on the seventh day after their adventure with the Sargasso Sea, the travelers closed the man hole, and with air tanks well filled slowly sank beneath the waves. Supper was eaten at a depth of sixty feet, and after the meal, while Washington was washing the dishes, the others sat and looked out through the bull's-eyes at the big fishes which floated past.

"I wouldn't like to catch one of them air things on my hook an' line," observed Bill, as a particularly large fish went past. "I reckon I'd have trouble landin' him."

"More likely he'd pull you in," said Mark.

For several minutes they watched the strange procession of deep-sea life. Presently Jack, who was sitting near the engine room door, sprang up. At the same instant there was the sound of an explosion.

"What's the matter?" cried the professor.

"Come quick!" yelled Washington.

"It's a fire!" yelled Jack. "One of the electrical fuses has blown out, and the ship is on fire!"



CHAPTER XIII

THE GHOST OF THE SUBMARINE

They all rushed toward the engine room. It was dark, because the lights had gone out all over the ship, and they could see only by the glare of the flames, which were increasing.

"Light one of the oil lanterns!" called the professor, and Bill did so.

"Unreel the hose," the inventor continued, and Mark and Jack ran to do this.

In a few minutes the line was stretched into the engine room, and water was being thrown on the flames, for Washington had started the pump as soon as he saw the conflagration.

The fire was in one corner, near the electrical switch board, and had been caused by the blowing out of one of the fuses, which occasioned the little explosion. The wood work near the switches was blazing fiercely, and soon the ship was filled with smoke.

"Empty the ballast tanks!" called the professor. "We must rise to the surface!"

"We'll all be burned up!" cried Tom. "First we nearly smother and then we get on fire. Neber saw such luck!"

With a rush the Porpoise began to rise, as her tanks were lightened. With steady hands, though with fear in their hearts, Jack and Mark continued to play the water on the flames, while the professor and Washington got out a second line and aided them.

"The fire is dying out!" exclaimed Mr. Henderson. "We'll soon get the best of it."

In five minutes the worst was over, though it had been an anxious time, and one of danger. The ship came to the surface, and the open man-hole let out the thick smoke that had nearly suffocated the travelers.

As soon as it was cool enough in the engine room an examination was made of the damage done. It was not as bad as the professor had feared, and the running part of the ship was not harmed. A new fuse was put in and the electric lights turned on.

The night was spent with the ship floating on the surface of the ocean, only enough speed being kept up to give her steerage way. The professor did not want to go below the waves until he had repaired the switch board.

Watch was kept, for, though they were out of the regular line of ocean travel, there was no telling when a vessel might come along and run them down, for the Porpoise did not show above the waves more than a few feet, and carried no lights.

Mark had the watch just after midnight, and was sitting in the conning tower, the door of which opened out on the small deck. He had swept the surface of the water with powerful glasses and was sure there were no ships in sight. So, feeling that he would like to stretch his legs, he walked up and down on the platform.

He had reached the after end, and was about to turn and go back, when he was startled to see between him and the conning tower a white object. At first Mark thought it was a cloud of mist, or something the matter with his eyes. He rubbed them, but the object did not disappear.

Then it moved, and, to his horror Mark saw that it had the shape of a man, tall and thin. The two arms were outstretched, and to Mark's imagination seemed to be pointed toward him.

In spite of trying not to be, Mark was frightened.

He did not believe in ghosts, and had always felt that all stories about them were due to persons' imaginations. Now he saw something that was hard to explain.

As he watched it, the white object turned and glided without making the slightest noise, toward the conning tower. It entered and Mark breathed a sigh of relief.

Perhaps, after all, it was some one from down in the cabin, maybe the professor himself in his night shirt, who had come up to see that all was right.

"I'll go and look," said Mark to himself.

He had to nerve himself for the ordeal, as, in spite of assuring himself that there were no such things as ghosts, he was frightened.

It was absolutely quiet. The only sound was the gentle swish of the water against the sides of the ship. The engine was running so slowly that it caused no noise.

Half way on his journey to the conning tower Mark paused. There, advancing toward him, was the white object. With outstretched arms it glided nearer and nearer until Mark's heart was beating as if it would burst through his ribs. His mouth was dry and he could not have cried out had he tried.

There was a splash in the water off to the left as some big fish sprang out and dropped back again. Involuntarily Mark turned in that direction. Then he thought of the ghost and looked for it again. To his surprise the white object was nowhere to be seen!

The boy waited a few minutes, and then, screwing up his courage, he went to the tower. There was no one inside, and, along the length of deck nothing was to be seen of the ghost.

"I wonder if I have been asleep and dreaming," the boy asked himself. He gave his leg a pinch, and the sensation of pain told him he was not slumbering.

"Well, I'll say nothing about it," Mark went on to himself. "They'll only laugh at me."

Entering the tower Mark looked for the glasses in order to make another observation. He could not find them, yet he was sure he had left them on a shelf in the tower.

"I wonder if the ghost took them," he said.

He heard some one coming up the iron stairs of the small companionway that led down into the interior of the ship through the man-hole. At first he thought it was his queer midnight visitor returning. Then the head and shoulders of Jack appeared.

"I've come to relieve you," said Jack. "Your watch is up; it's two o'clock. Here are the night glasses. I found them on the cabin table. I thought you had them with you."

"I did," replied Mark.

"Then how did they get below?"

"I—I don't know," said Mark.

The mystery was deepening, yet he did not want to tell Jack just yet.

"Well, that's queer," remarked Jack. "Maybe the captain came up and got them while you were asleep."

"I didn't go to sleep," answered Mark rather crossly.

Jack said nothing more, but took his place in the conning tower, while Mark went below. Thinking to discover if the ghost might by any chance have been one of the persons on the Porpoise, Mark looked into each bunk. From the captain to Washington, all the inmates were peacefully slumbering.

"Queer," murmured Jack, as he took a look into the engine room before turning in. The engine needed no attention, as it worked automatically, and all there was to do was to steer the ship. Even this needed little care as the course was a straight one, and the wheel could be locked, leaving the lookout little to do.

"Did you see anything during your watch?" asked Mark of Jack the next morning.

"See anything? What do you mean?"

"I mean anything unusual."

"Nothing, only a school of porpoises went past and gave me a little scare. They were like a lot of water kittens at play."

Mark concluded he would say nothing of the white visitor until he ascertained whether any one else had seen it.

It was several nights later, when the ship was once more proceeding slowly along the surface of the water, that the ghost again appeared. This time Washington had the midnight watch.

But the colored man was not one to remain quiet when he had such a scary visitor, and his yells aroused the ship.

"It's a ghostess! A big white ghostess!" yelled Washington. "I don seen it wid my eyes, an' it waved his arms at me. I's goin' to die suah!"

"What's all this nonsense?" demanded the professor sternly. Then Washington, more or less excitedly, told of what he had seen. It was just as it had happened to Mark.

"You were dreaming," said the professor to Washington. "There are no such things as ghosts."

Every one, from old Andy to Tom and Bill, had been roused by Washington's cries, and listened to his story. At the close of the recital of how the white thing had suddenly disappeared, Washington refused to continue his watch, unless some one stayed with him.

Mark volunteered to do this. He was anxious to see if the ghost would reappear to him. But nothing happened; and the rest of the night passed off quietly.

The next day the Porpoise was taken below the surface, in order to allow of better speed being made. She was running along, submerged to a depth of two hundred feet, when there came a sudden jar, and the ship stopped.

"More trouble!" exclaimed the professor.

He opened the slide covering the bull's-eye windows and looked out. All about was swirling muddy water.

"Can you see anything?" the inventor called to Jack, who was in the conning tower.

"We've run into a mud-bank, and are stuck fast," called back the boy.



CHAPTER XIV

DIGGING OUT THE SHIP

"Reverse the engine!" called the professor. "Maybe we can back the ship out."

Washington set the big screw to revolving in the opposite direction. The Porpoise shook and shivered but the mud held her fast.

"We must have gone in pretty deep," commented Amos Henderson. "Luckily it was soft mud instead of a rocky reef or we'd have damaged the ship beyond repair."

For several minutes the engines were kept on the reverse, but all to no purpose. The sticky mud was like glue in its holding power and the ship had buried her prow deep into it.

"I guess we'll have to dig our way out," said the professor, after taking a careful view of the big mud bank from the conning tower. "Washington, get out the diving suits and the spades."

"Are we really going out in the water to dig?" asked Tom.

"Of course," said Mr. Henderson. "You'll be as safe as in the ship, wearing one of my diving suits. We'll all have to help, for it will be quite a task."

The queer suits were brought out, and the reservoirs in the helmets were filled with compressed air. It was decided to have Washington remain within the Porpoise, to watch the machinery and start the engine when the digging was partly done, in order to see if the ship would not pull herself free when some of the mud had been removed from the prow.

"And we may need Washington for another purpose," said the professor.

"What for?" asked Mark.

"Well, he'll have to stay by the diving tank, to let us in quickly in case of emergency."

"Do you think there'll be an emergency?" asked Jack.

"You never can tell," was the answer. "We are in deep water, and I don't want any accidents to happen."

In a few minutes all save Washington were in their diving suits and ready to go out and walk on the bottom of the sea. They entered the tank, the door was closed, and then water was slowly admitted from the ocean. When the tank was full, led by the professor, they stepped out on the muddy floor of the ocean.

At first the pressure of the water at so great a depth bothered them. But, as we know, the diving suits were reinforced with plates of steel, and so strong that little more than an extra weight of water was noticed. They soon became used to it. Each one carried a spade, while the professor, Andy and the boys each had, slung about their necks by straps, one of the electric guns.

Cautiously they walked toward the big mud bank. They had to go slowly because of the weight of the water above them, and because they might at any minute step into some muck hole and sink down. Fortunately, however, they found there was a firm bottom right up to where the bank of mud reared upward.

Turning on the electric lights in their helmets, the voyagers were able to see quite distinctly. The Porpoise had rammed her nose into the under-water hill for a distance of about ten feet. It was going to be no easy matter to get her free, but the divers lost no time.

Vigorously they attacked the big hill of mud. They dug their spades in and tossed the earth to one side. It was a strange place to work. At first the weight of water hampered every one, but they soon became used to it and were able to proceed more rapidly.

From the conning tower Washington kept watch of their progress. When they had gone in about five feet he started the engines, hoping the Porpoise might now pull herself free. But the mud still held.

By signs, for it was of course impossible for any one to hear or speak, attired as they were in helmets and suits, the professor motioned that they must dig deeper.

Once more they attacked the big mud bank with their shovels. Farther and farther they went into the muck until it seemed that the nose of the submarine must be free. But when Washington started the engines it was obvious that the ship was still held.

Again the digging was resumed. All at once, while every one was wielding his spade to best advantage, a shadow seemed to cover the water. It loomed up large and black, and the professor stopped and gazed upward. What he saw made him drop his spade and grab the gun that was about his neck.

Floating in the water above the diggers, were three immense sharks. Their cruel mouths were partly open, showing three rows of big teeth, and they were slowly turning over on their backs to make a sudden rush and devour the men and boys. Owing to the peculiar shape of its maw a shark can not bite until it turns over.

The professor motioned for Bill and Tom to move behind him, and signalled for Jack, Mark and Andy to stand close with their weapons ready.

The sharks floated lazily downward as if they knew they had the diggers at their mercy. To run and escape was impossible, for no one could run hampered by the weight of water and his diving suit.

One of the terrible fish opened its mouth wider and, with a flirt of its tail aimed straight for the professor. Mr. Henderson raised his gun, and took careful aim at the middle of the fish, half turned over. Unerringly the electric bullet sped on its way. It entered the soft under part of the shark, and immediately the thing struggled in its death agony.

The water was dyed with blood. At the same instant the other sharks rushed forward in a swirl of foam. The boys and Andy fired as best they could, and must have hit one of the creatures for there was a greater commotion.

But the fight was not over. Instantly the ocean seemed alive with the giant fish. Attracted by the blood of the killed ones, scores of the tigers of the seas rushed toward the scene of combat making matters livelier than ever.

The professor, the boys and Andy fired their guns at random. Redder and more red became the water until their helmet lamps barely glowed in the crimson sea. It seemed that a whole army of the voracious sharks had attacked them.

The professor realized that to stay and attempt to fight all the sharks in that part of the ocean was impossible. He motioned for the boys and Andy to follow him. Then he slowly led the way back to the ship.

But the sharks were not to be gotten rid of so easily. Several of the largest followed the diggers, their horrible eyes, and big mouths with rows of cruel teeth, striking terror to the hearts of all.

One of the creatures made a rush for Bill and Tom who were close together. Either or both of the men would have been bitten in twain, in spite of the protection of their diving suits, had not Mark, with a snap shot, killed the fierce fish.

It was now a running fight, and yet not so much that, because to run was impossible. However, they hurried all they could, and, by dint of quick firing kept the ugly creatures at bay until the side of the ship, where the diving tank was placed, was reached.

The professor stepped to one side, and motioned for the others to proceed him in entering. Little time was lost. As Bill, the last one in, stepped past the steel door the inventor attempted to enter. To do so he had to let go of his gun.

Instantly one of the sharks made a rush for the old man. But Andy was on the watch. He leaned forward, and, from his weapon sent a bullet straight down the throat of the monster. The electric missile did its work well, and the lifeless body of the shark was devoured by the others of its tribe.

The professor pulled the door shut behind him. Then he set the pump to work to empty the tank. As he did so there was a tremor to the ship. What could it mean?

In a few minutes the tank was empty and the divers stepped out into the ship, freed from the oppressive weight of water. The ship continued to vibrate and seemed to be in motion.

"What is it?" asked Mark as soon as he had his helmet off.

"De ship am free! We've got off de mud bank!" exclaimed Washington, running in from the engine room.

It was true. Enough had been dug so that, with the power of the screw working backward, there was sufficient force to pull the Porpoise from her perilous position.

"Empty the tanks and rise to the surface," said the professor.

In a few minutes the ship was on top of the waves, the adventurers freed from the double danger of the mud and sharks. They congratulated each other on the good outcome of the fight with the monster fishes.

Wearied with their labors and the battle under the waves, the travelers sat up on the deck breathing in the fresh breeze. Then, after a while, supper was made ready and eaten with good appetites.

It was decided hereafter to sail along near the surface at night, and not to submerge the ship deeply save during daylight, when it was easier to distinguish objects under the water.

Following this plan the Porpoise steamed along just awash that night, and the next day was sent down about fifty feet below the surface.

One afternoon, when the travelers were resting, having partaken of a fine meal, the professor went on deck to make some observations, the ship having been raised for that purpose. He came down, somewhat excited.

"Well, we're half way to the pole," he announced.

"How can you tell?" asked Mark.

"Because we have just crossed the equator. We went over the imaginary line three minutes ago."

"I was wondering what made it so warm," said Jack.

"I guess you dreamed it was hotter," spoke the professor. "It has been just as hot as this for the last few days. Crossing the line makes no difference."

"Then we are really in the southern hemisphere now," said Mark.

"That's where we are," replied Mr. Henderson.

He put his instruments away.

"Well, we may as well go below the surface again," he remarked.

"Come quick! Hurry up!" yelled Washington from the deck. "Dar's a shipwreck up heah! Somebody's on it!"



CHAPTER XV

THE STRANGE SHIPWRECK

The professor, followed by the boys and Tom, Bill and Andy hastened on deck. They saw Washington pointing excitedly off to the west. There, rising and falling on the easy swell, was the wreck of a large vessel.

She had been a three masted schooner, but now only the stumps of the masts remained and the craft was rolling to and fro. It had settled low in the water, and was quite deep by the head, so that, at times, the waves broke over the bow in a shower of spray.

But what attracted the attention of the adventurers more than anything else was the sight of two figures near what had been the after cabin of the ship.

There they stood, frantically waving their hands toward those on the submarine. Across the water that separated the two craft, there came a faint hail.

"I suppose they are nearly dead," exclaimed the inventor. "We must save them."

He ordered the Porpoise sent ahead slowly toward the wreck. The distance was about half a mile, and was soon covered. As the submarine approached closer those on the schooner could be observed more plainly.

"One of 'em is a woman!" exclaimed Jack, who was using the glasses.

"Let me see," spoke the professor.

"You're right," he added. "The other is a little girl."

A few minutes later the Porpoise was alongside. The woman and child came to the rail of the schooner, which was barely five feet above the waves.

"Can you jump down, or shall I come aboard and get you?" asked Mr. Henderson seeing the woman hesitate.

"I can jump down, if you will catch the child," said the woman. "Oh I am so glad you came," she added. "We are almost dead from hunger and thirst, and the wreck is ready to sink and cannot last many hours longer."

"Pass the little girl down to me," spoke Andy. "Then you jump. We'll save you all right."

The little girl reached the deck in safety, and the woman, who proved to be her mother, followed.

"Now take us to your ship," said the woman.

"You must be a long way from her, as she is not in sight."

"Our ship is right here," spoke Mr. Henderson with a smile.

"Where, I don't see her," and the woman looked in all directions.

"Allow me to introduce you to Profess Amos Henderson's famous submarine, the Porpoise," spoke the inventor with a bow. "But come, let us go below. You must be suffering, and here I am making speeches."

"Indeed I am hungry, and thirsty too," said the woman. "So is Nellie. But I thought this was merely a small boat, sent from some large ship to get us."

The woman and girl descended to the cabin of the submarine, where Washington set before them a fine meal. Under the advice of the professor they partook sparingly of food and drink at first, as, having eaten nothing in many hours, the inventor said they must begin by taking a little at a time.

As soon as they had finished and become somewhat rested, the woman told her story. She was Mrs. Johnson, a widow, her husband having once owned and been captain of the schooner that was wrecked. After his death she and her daughter, having become part owners of the craft, disposing of a third interest to the former mate of the ship, had set out on one of the voyages to South American ports.

They had had good weather going, and took on a valuable cargo of lumber and rare woods. But the return trip was more perilous. Heavy storms had buffeted the craft almost from the time of leaving port, and in one heavy blow, ten days before, the ship had been wrecked.

"What became of the crew?" asked Mr. Henderson.

"They took to the boats," replied Mrs. Johnson. "My little girl and myself were to go with the mate and his men. The waves were fearfully high, and, as they held the boat close to the schooner so we could get in, a big roller smashed the little craft. The men must have all been drowned for I never afterwards caught sight of one of them."

"But the other boats?" asked the inventor.

"They had gotten too far away to hail, supposing that I would be taken care of by the mate. There was nothing for Nellie and I to do but stay on board, expecting the ship to sink every minute."

"And you have been there ever since?" inquired Andy.

"Ever since. That was ten days ago. Every day I thought it would be our last. The storm passed away and the sea became calm but the ship kept settling lower and lower. Only the fact that part of the cargo was wood kept her afloat so long. I managed to get some provisions and water up on deck, but the sea had spoiled most of the stuff. We had to eat only a little at a time, as I knew it would be some days before we could be rescued, if we ever were. Two days ago we ate the last of the food and drank almost the last of the water."

"Then you had nothing since then," spoke Jack.

"Only a few drops of rain that I caught on a piece of sail," answered Mrs. Johnson.

"Never mind, you can have all you want now, mother," said Nellie, coming over to pat her parent's cheek. "Oh," the child went on, "I was so thirsty I could just cry when I thought of such things as ice cream sodas."

"I guess you could," agreed Mark. "Well, we can't give you any soda water, but we have plenty of the other kind."

Mrs. Johnson was much interested in the Porpoise and Professor Henderson showed her all about the craft. Though the quarters were rather cramped, a small cabin was fitted up for the lady and her daughter.

"We will travel a bit under the water so you can get used to it," said the captain after a tour of the ship had been made. The tanks were filled, and the Porpoise sank beneath the waves. At first Mrs. Johnson was much frightened, and Nellie cried. But when they saw how skillfully the ship was managed, and how easy it was to rise again, they lost their fears.

For several days the voyage was continued. Mrs. Johnson and Nellie remained aboard as there was no place to land them, and they said they wished to stay until they met some ship sailing north.

One day, just at dusk, when the Porpoise, after a long run under the water had come to the surface, the professor, came up on deck to take a look around. Washington and Andy accompanied him.

"Looks like land, off there to the left," remarked the old hunter.

"Get the glasses, Washington," said Mr. Henderson. "It may be a ship."

He took a long and careful look through the binoculars.

"It's some sort of land," he announced. "We'll go over in the morning and see what it is. Probably it's an island, for there's no main land in these parts. We are in the middle of the southern Atlantic now."

The next morning, after breakfast, the Porpoise was headed toward the dark spot on the surface of the water that the professor had gazed at the evening before. As they came nearer it was seen that the place was a large island.

"But it's a mighty queer one," spoke Mr. Henderson. "It looks more like a big volcano than anything else."

As the ship came nearer it was seen that this was true. The island rose abruptly from the surface of the sea in a big ridge, slightly rounded. There appeared to be no signs of life on the land, but in the air overhead hovered several big birds. These circled about and then fluttered down, seemingly about the middle of the island.

"We'll sail around and see if there's a place to land," spoke the inventor. "There doesn't seem to be a good harbor on this side."

Slowly the Porpoise made the circuit. The island appeared to be almost round. When they had gone about half way around Andy, who was staring ahead, cried out:

"Look out Professor! Don't go any nearer or we'll be sucked into the whirlpool!"

The inventor looked where the hunter pointed. Then he beheld the strangest sight he had ever seen. The island was low toward where Andy pointed and they beheld the waters of the ocean pouring over the edge of it, and falling down into an immense hole with a roar like that of Niagara Falls.

"Reverse the ship!" cried Professor Henderson. "Send her back quickly, Washington, or we'll be sucked down!"

The colored man lost no time, and the big screw was sent whirling in the opposite direction. And it was high time, for already the onward rush of the falling waters was slowly drawing the ship toward the big cavern.

"That was a lucky escape," commented Amos Henderson. "Well, as we can't land there we'll try the other way around."

The ship was headed in the opposite direction, and, after an hour's sailing, a good harbor was discovered. The Porpoise was anchored in shallow water close to the shore and in a small boat the professor, Andy and the two boys went to the strange island.

They found it merely an immense circle of land with the middle part taken up by the big hole. And such a hole as it was! It was so wide across that they could not see the farther side, and the depth they could only guess at. Looking down they could only see great rolling masses of clouds or vapor.

"Perhaps it's steam," suggested Jack.

"Maybe it is," agreed the professor. "If this is a volcano, with lava in it, the water of the ocean, pouring in on the other side, may be changed to steam."

"Do you suppose this hole leads to the centre of the earth?" asked Mark. "I've read somewhere, that the earth is hollow."

"Some scientists believe it," commented the professor. "This looks like a big enough hole to lead clear through to China. Hark, you can hear the roar of the water now."

They listened, and the wind brought to them the sound of the sea pouring down into the unfathomable depths.

"Let's throw a big rock down," suggested Jack. "Maybe we can hear it strike bottom."

With the aid of Mark he cast a big boulder down into the depths. They listened intently, but not the slightest sound echoed back.

"I guess the bottom is too far away for you to hear the stone land," said the professor.



CHAPTER XVI

THE GHOST AGAIN

They spent some time looking down into the hole. The masses of vapor, or clouds, rolled and swirled hundreds of feet below them, but never broke sufficiently to allow of a clear sight.

"Well, we had better go back to the ship," remarked the professor. "We must continue our voyage."

They were soon on the Porpoise and steaming away from the strange island, the inventor deciding to get far off out of the influence of the terrible waterfall.

The night was, as usual, spent with the ship slowly steaming ahead on the surface of the water. It was getting on toward twelve o'clock and Washington had the watch. He was to be relieved by Jack.

The latter had been awakened by the alarm clock at the head of his bed, which time-piece he had set to arouse him so that he might take Washington's place. Jack was just getting the sleep from his eyes by a vigorous rubbing when he heard a loud yell.

"Land a' Massy!" cried Washington from the deck above. "I's goin' t' die suah! De ghostess am after me ag'in!"

Without waiting to dress, Jack sprang up the ladder and was soon out on the deck. He saw Washington kneeling down in front of the conning tower door while, at the after end of the deck, was a mysterious white object; the same strange shape that had been observed before.

"I'm going to solve this puzzle!" exclaimed Jack to himself as he made a dive toward the object in white. "This ghost business will have to stop!"

But, unfortunately for his plans, his foot slipped on the smooth steel deck, and he went down in a heap. When he got up the ghost was nowhere to be seen.

Washington, however, was still kneeling down and praying to be spared from the attack of the midnight visitor. Jack limped over to the colored man.

"Keep still," said the boy. "It's gone now. What was it, anyhow?"

"Some ghost from de grabeyard," replied Washington.

"When did you see it first?" went on Jack.

"'Bout ten minutes ago," replied Washington.

"Well it's gone now," said Jack, though he had to admit to himself that the affair was somewhat puzzling. Professor Henderson had been awakened by the yells of the colored man and came on deck to see what the trouble was. He appeared somewhat annoyed when Washington told him what had happened.

"There are no ghosts!" declared the inventor in positive tones.

"You wouldn't say so, Perfessor, if you'd seen him," spoke Washington. "He were all in white, tall an' slim, an' big red eyes, an' a green nose, an' fire comin' from his mouth an'—"

"Nonsense," interrupted Jack. "It was nothing but a white object, Professor Henderson. I saw it."

"And what do you think it was?" asked the inventor.

"I—I can hardly say," replied Jack. "Of course I don't believe in ghosts, but this—"

"It was probably a mist from the ocean," interrupted the professor. "Don't let me hear any more of it. Washington, go below. Your watch is up and Jack will take charge. I don't believe there will be any more ghosts."

Nor were there that night. The Porpoise glided along, requiring little attention, and when morning broke was several miles nearer the southern pole.

The journey was continued beneath the waves and it was found much cooler under them than upon the surface, for the ship was in the midst of the equatorial heat.

About four o'clock in the afternoon, when all was quiet aboard, there came a sudden yell from the engine room. Washington's voice could be heard calling for help. Then it died away in a groan.

"Something has happened!" called Jack. "Washington is in trouble."

He hurried toward where the machinery could be heard buzzing. The professor, with Andy and Mark followed. They expected to see the colored man caught in some shaft or belt, but he was nowhere in sight.

"Perhaps he has fallen into the ocean," suggested Mark.

"The engine room does not open into the sea," answered the professor.

A deep groan came from some corner of the engine room.

"There he is!" cried Jack.

But a careful search failed to reveal Washington. Still he could be heard to groan at intervals. Bill and Tom came and aided in the search, while Mrs. Johnson, who was worried at the unusual activity, asked what the trouble was.

Captain Henderson did not tell her, for, as he said afterward, he did not want any women fainting away on his ship. At his request Mrs. Johnson went back to her cabin, and the hunt for Washington continued.

"Here he is!" cried Jack at last.

The boy had climbed up on a small ladder that led to the big storage battery tanks. He had looked down, and there, in the large metal box had spied the colored man on the bottom. Washington was unconscious and breathing heavily.

"He has been overcome by the fumes of the sulphuric acid!" exclaimed the professor. "We must get him out quickly or he will die!"

"I'll get him!" cried Andy.

The old hunter grabbed a small step ladder that stood against the wall of the engine room. With this on his shoulder he climbed up the steps which led to the top of the storage battery tank. Then, by means of his ladder, he descended inside.

He had to work quickly as the fumes were very strong, but he managed to hoist Washington up so that Bill and Tom, from outside, could take hold of him. Then the colored man was carried out on the deck, where the fresh air and some restoratives the professor used soon revived him.

"Is I dead," were Washington's first words, as he sat up and looked about him.

"Not this time," replied the professor. "You had a close call, though. How did it happen?"

Washington explained that he started to clean the battery tank, when he lost his balance and fell in. He cried as he felt himself falling, but as soon as he struck the bottom of the tank the fumes of the chemicals made him unconscious. His deep breathing, which had sounded like groans, alone served to attract attention to his location.

In a little while Washington was all right save for a slight weakness. Captain Henderson made him go to his bunk, and ordered him to remain there until morning.

During the excitement over Washington's mishap all thought of steering the ship had been forgotten, and when Mr. Henderson went to the conning tower about five o'clock he found that the Porpoise was several points off her course and was headed to the east instead of to the south. How many miles out of her way the craft had steamed could only be guessed, but as she had been going wrong for nearly an hour, it must be quite a few the inventor calculated.

However, he said, no great harm had been done. Even this slight accident would not have happened had not Bill, who was in the conning tower steering, forgotten to put the automatic device in operation when he left the wheel to join in the search for Washington.

"We'll soon make up the lost ground," said Mr. Henderson. "Another week or ten days ought to see us at the end of our journey."

"And what will we do when we get there?" asked Jack.

"We will make some important geographical and scientific observations," said the professor. "Not only that, but we will have done something that no living person has ever accomplished. We reached the north pole, though we could not land on the exact spot. Let us hope we will be more successful regarding the south pole."

The professor set the ship on her course again. Bill and Tom got supper in place of Washington, while Mrs. Johnson helped set the table.

The meal was eaten, and then the inventor started the ship toward the surface, following the plan of not sailing beneath the waves after dark, in order to avoid accidents.

The craft was making good speed ahead, with the big screw revolving in the tunnel and spurting the water from the rear, when there came a sudden jar, and everyone nearly toppled over from the quick stopping of the Porpoise. At the same time the forward end seemed to go up in the air.

"What has happened? Are we sinking?" cried Mrs. Johnson.

"I think we are going up," spoke the professor in cool tones.

"In the air?" asked the lady.

"On the land," answered the inventor. "I think we have struck shore and slid up on a beach."

He ordered the engine stopped and hurried to the conning tower to make an observation. He turned on the searchlight and looked carefully at what the beams showed. Then he came back to the cabin.

"Well, what is it?" asked Mrs. Johnson.

"We have gone ashore, just as I supposed," said Mr. Henderson.

"And whereabouts are we?"

"On the coast of South America."

"Near where?"

"Near Terra Del Fuego, the land of fire!"



CHAPTER XVII

ATTACKED BY SAVAGES

"Are we in any danger?" asked Mrs. Johnson.

"I hope not," replied the captain. "If the ship is not strained the rising tide will probably float her safely, and we can continue our trip. We will have to wait until morning to see, however."

"And if the ship is damaged?"

"We will have to do what we can. We will hope for the best, madam."

The professor went on deck. His first opinion of the accident was confirmed. The Porpoise, in emerging from the waves, had slid well up on a sandy shore, where she was held fast because the tide was rapidly falling. It would be twelve hours before there would be a chance of her floating again.

The mishap had occurred because the ship had gotten off her course when Washington's accident occurred, and had not been set right in time.

However, as Mr. Henderson had said, there was no particular danger, unless it was found that some of the plates had been strained, which might cause a leak.

The night was passed with the nose of the Porpoise well up on shore, and before morning, as the tide continued to fall, more and more of the craft became exposed until the whole steel body rested on the sloping beach.

Jack was the first to awaken. He was up with the sun, and went out on the deck to take a view of the country he had often heard about. A stretch of wild landscape met his eyes, and to the left and right of the ship the waves were breaking on jagged rocks.

"It's a good thing we didn't hit the rocks," thought the youth.

Mark came up on deck, and the two boys looked over the scene. It was a strange one. Beyond the beach was a low level country, green in places, with now and then a patch of what looked like trees.

"And what are those brown spots moving about?" asked Mark.

"I guess they are herds of cattle," replied Jack. "You know South America is a great place for them."

For half an hour the two lads gazed about. Except for the stern of the Porpoise all of the craft was now out of water, and one could have jumped from the low deck down to a mound of white sand of the beach.

"Let's go ashore and take a run," suggested Mark. "I've almost forgotten how to walk on dry land."

"Go ahead," answered Jack. "I'm with you."

"All right."

The boys lost no time in getting down to the beach. They found it hard and firm, and made their way to the strip of grass-covered land lying beyond. Up and down they wandered, finding many curious and beautifully marked shells where the waves had washed them.

Suddenly Jack gave a big jump and let out a yell.

"What's the matter?" asked Mark.

"I thought I saw one of those cocoanuts move," answered Jack, pointing to where several of the big shaggy fruits lay under a tree from which they had fallen.

"I guess you're right," spoke Mark. "I certainly saw one of them take a little side step. I wonder what does it."

As the boys watched they were surprised, to see one of the cocoanuts come toward them, apparently advancing without any visible means of locomotion.

"This is a queer country," remarked Jack, getting ready to run in case the strangely moving cocoanut might be a warning of danger.

"Look! There's a whole lot of them moving," cried Mark.

Sure enough a dozen or more of the nuts began to advance toward the lads. The boys were not so much afraid as they were surprised. But a few seconds later the reason for the strange sight was made plain.

As they looked they saw one of the nuts roll down a little mound of sand. Then they noticed that a big land crab was on the tiny hill and it was evident that the nut had fallen from his claws.

"It's the crabs!" exclaimed Mark. "I remember reading about them now. They come ashore from the water where they live part of the time and get the cocoanuts. Then they smash the shells by pounding the nuts on a stone and eat the white meat inside. They are called cocoanut crabs."

"I was beginning to think we were in some enchanted land," spoke Jack.

"Well, it certainly looked queer," agreed Mark.

For some time the boys watched the strange sight. Then they walked along the beach, seeing several large star fish, and some big horse-shoe crabs that had been stranded by the tide.

"Look at that immense turtle!" exclaimed Mark, as one of the creatures scuttled over the sand toward the sea. "I'll bet she's been laying eggs!"

"Perhaps so."

They made a rush for the tortoise but were not quick enough, for she slid into the water and made off.

"Here's her nest, anyhow," called Jack, as he pointed to some eggs, thinly covered with sand. "Let's go back and take them with us. I've heard they are good eating."

Jack and Mark started to gather up as many of the eggs as they could in their hats. While they were thus engaged they heard a call from the ship and looked up to see coming toward them, all of the ship's company except Washington.

"I wonder if anything could have happened," spoke Mark.

He and Jack dropped the eggs and started on a run toward the stranded ship. They were reassured, however, when they saw the professor waving his hand at them. When he got within hailing distance the inventor called:

"It's all right, boys. We're just taking a little walk, before breakfast, for an appetizer. It's been some time since we were on land. Washington says he'll have some fine fried ham for us in a little while."

"And here are the eggs to go with it," spoke Jack.

"Have you found a hen house?" asked Mr. Henderson in some wonder.

"No, but we discovered a turtle, which is just as good," replied Mark. The professor agreed with him, and called for Washington to come and get the eggs.

"Wall I 'clare to goodness!" exclaimed the colored man as he gathered the product of the turtle up in his cook's apron. "Dis suttinly am a queer contraption of a country to find eggs growin' in de sand."

He shuffled back to the ship, while the others walked up and down on the beach. In about half an hour the professor suggested that they return.

"Washington must have breakfast ready by now," he said, "and I, for one, am hungry enough to enjoy it."

They turned toward the stranded Porpoise but no sooner had their eyes taken in the sweep of the ocean that lay before them than they uttered cries of fear.

Spreading out from the beach in a big half circle that enclosed within its curve the submarine, were three score of canoes, each one filled with half naked savages.

"The natives are going to attack the ship!" cried the professor. "We must hurry back or we are lost!"

He started on the run, accompanied by the boys and men. Mrs. Johnson and her daughter brought up the rear. The adventurers had gone from one misfortune into another.

At the top of their speed they approached the stranded ship. The natives saw them coming and the next instant hundreds of paddles broke the waves into a mass of sparkling water as the wily savages urged their canoes swiftly toward the submarine.

"If we can only reach it first we can hold them off until the tide floats us, and then we can escape," said the professor.

He increased his pace though the run was beginning to tell on his aged frame. The adventurers were now within an eighth of a mile of the ship, but the savages were closer, and had the advantage of being able to make greater speed. The two forces approached nearer and nearer. Finally the first of the canoes reached the submerged end of the Porpoise.

With wild shouts a score of the brown men leaped from the boats and scrambled up the steel sides. An instant later they were joined by several canoe loads of their companions. They swarmed up on the deck, and some peered down the winding stairs that led to the interior of the ship.

"Too late!" cried the professor. "They have captured the Porpoise!"

"But Washington is aboard!" shouted Jack.

As he spoke the colored man was seen clambering up out of the companion way. He gave one look at the wild natives who swarmed over the ship, and then, with a yell to be heard a long way off, disappeared below.

The shouts and cries of the savages grew louder and they seemed to be doing a sort of war dance.

"We must make one effort to drive them away," said the professor in desperation.

"We haven't even a revolver," spoke Andy.

"Let's use stones," suggested Jack, grabbing up a handful from the beach.

"Look out!" yelled Mark. "They are going to shoot some arrows!"

A second later a flight of the weapons filled the air. Fortunately the natives were too far away to permit the shots taking effect, but it showed that they intend to fight and take possession of the ship.

Even this did not frighten Mr. Henderson. His vessel was more than life to him and he kept on. Several arrows fell dangerously close and he might have been hurt had not old Andy run after him and induced him to go farther up the beach and out of harm's way.

"They will kill Washington!" cried Jack as he thought of the colored man at the mercy of the savages.

"There he comes!" yelled Mark.

He pointed toward the ship and as they all looked in that direction they saw the colored man climbing out on the deck. Under one arm he bore a long narrow box, and in the other hand he carried one of the electric guns.

"He's goin' to fight 'em!" exclaimed Andy. "He's got a gun and he will show 'em what's what!"

But Washington did not seem to have any such intentions. With a yell that equalled the savage cries of the natives, he sprang over the side of the ship, onto the sand and ran toward the group of adventurers. A flight of arrows followed him, but he was not hit.



CHAPTER XVIII

ON LAND

"Why don't he shoot his gun at 'em?" demanded Andy, capering about on the sand. "He could soon scare 'em off!"

"I'm afraid Washington is too frightened to do anything like that," answered Professor Henderson. "He is lucky to have escaped alive."

"Wait until he gets here with that gun, an' I'll do some huntin' that will make them savages skip!" exclaimed Andy.

In a little while Washington came up to where the others from the Porpoise stood on the beach. The colored man was panting from his run.

"De most monstrous disproportionately extradition ob circumstantial occurrances dat ever transpositioned on my optical vasionariness!" he exclaimed as he laid his gun and the black box carefully down on the sand. "Ten thousand naked imps of darkness swarmin' ober de ship an' not a pusson to say what dey ought to do an' where dey ought t' go! It am suttinly terrible!"

"Why didn't you shoot some of 'em?" demanded Andy.

"Me?" exclaimed Washington. "What for I want t' shoot 'em? S'pose I want 'em t' git mad at me?"

"Well, you're a great one," went on Andy, picking up the gun. "I guess I'll have to take a few shots myself."

"Yes, sah."

From Washington the adventurers learned how the savages had silently come up in their canoes and surrounded the ship, gaining possession of it before he could make any effort at defense, even had he so desired.

"What are we to do now?" asked Mrs. Johnson, when they had retreated out of sight of the savages. "The natives have possession of the boat, and how are we to regain her when there are so many of them?"

"It certainly is a hard nut to crack," admitted the professor. "We will have to camp out on the beach for a while and see what happens. Perhaps they may leave the vessel when they find it will do them no good. They can't run her."

"But they can tear her all apart and damage the machinery," said Jack. "Then we would be in a pickle."

"Well, we won't hope for any such bad luck as that," interrupted the professor. "We will look for the best."

"When are we going to have breakfast?" asked the little girl, after a long wait. "I'm hungry, mother."

"We will have it pretty soon," replied Mrs. Johnson in order to quiet her daughter's mind.

"But I want it now," continued Nellie. "I'm very hungry."

"Hush!" said Mrs. Johnson.

"An' I had de finest brekfust what was ever invented," said Washington, rolling his big eyes. "Mud turkle eggs, ham, preserves, coffee—"

"That will do, Washington," said the professor. "It only makes our mouths water to think about such things."

At the mention of the turtle eggs Jack nudged Mark, and signalled him to walk to one side. When they were out of earshot of the others Jack said:

"What's the matter with cooking some of the eggs that are left on the sand? There are plenty of them, and there is no sense in our going hungry."

"How you going to cook 'em?" asked Mark.

"I'll show you," replied Jack.

He scooped a hollow place out in the sand until he had quite a hole. This he banked up with stones until he had a small oven. By arching the stones over toward the top there was left a sort of circular opening. Over this Jack fitted a monster clam shell, with the concave side uppermost.

This made an improvised stew pan. Underneath was piled small bits of dry drift-wood, which a match soon set on fire. In a little while the water in the big shell was boiling.

"Now get some other shells for dishes," said Jack to Mark.

Soon Mark had piled up a lot of smaller shells.

"Help me gather some eggs now," said Jack, "and we'll put them in to boil. Then we'll invite the rest of the folks to breakfast."

The two boys soon uncovered from the sand a pile of the eggs, and in a little while they were steaming in the hot water. Then Jack arranged the shell-dishes on the sand. He went over to where the others were gloomily considering their plight.

"Breakfast is ready," he announced.

"This isn't any time for joking," spoke Professor Henderson, rather sternly.

"But I mean it," went on Jack. "Just come over and see. I'm not fooling you."

Wondering what he had done they all followed him.

"Welcome to Hotel Terra del Fuego!" cried Mark. "We haven't much of a variety, but what there is we can recommend."

He began to dip the eggs out of the water with a bit of shell and placed them on the improvised dishes.

"Everyone sit down," commanded Jack. "The bill of fare is ready."

They all joined in the short laugh that followed, and soon were seated in a circle about the beach-oven. The eggs proved to be very good, even though there was no pepper. The salt of the sea water they were boiled in was more than sufficient.

"Now if there was only bread in that ammunition bag Washington brought with the gun," said Andy, "we wouldn't want a better meal."

"He'p yo'se'f!" exclaimed the colored man with a grin as he extended a canvas bag that was tied to the stock of the electric gun.

The old hunter opened it and found it filled with ship biscuits.

"Well I am stumped!" he exclaimed.

"I grabbed up de wrong thing in my haste," Washington explained. "I thought I had de electrical lightning bullets, but I didn't. Howsomever de gun's got some in de chamber."

"It's a lucky mistake," commented the professor as he munched a biscuit and an egg. "Bullets are good but these are better, when one is hungry."

They managed to make a fairly good meal, so that even hungry Nellie was satisfied. The boys found a spring of fresh water up on shore, and this furnished something to drink, for which they were grateful.

They sat about on the beach, after the breakfast and discussed what they had better do. It was evident that an attempt to regain possession of the ship, with their small force and only one weapon, was out of the question.

"We've got to use strategy," said Andy. "If we could play some trick on the savages we might scare them away. Otherwise I don't see what we are to do."

"It's a bad state of affairs," replied professor Henderson. "Even if we got the ship we might find it so badly damaged that it would be impossible to run it. It is a terrible thing," and he heaved a deep sigh.

The hours passed with no change in the situation. The savages remained in possession of the submarine, and did not seem inclined to quit the vessel. Most of them were inside, but quite a number paddled about the stranded craft in their canoes.

There was nothing for the adventurers to do but to await developments. With no chance of attacking the force of natives, they might consider themselves lucky if the savages did not come ashore to give battle.

The sun was high in the heavens when, in the shade of a big tree where they had all taken refuge from the heat, Nellie again announced that she was hungry.

"I guess the boys will have to provide another meal," said Mr. Henderson.

Jack and Mark said they guessed they could find some more turtle eggs, and Washington volunteered to accompany them. As they were looking for a nest in the sand they saw one of the tortoises scurrying down to the ocean.

"Git her, quick!" cried the colored man. "Turn her ober on her back!"

The boys did so, though they did not know what Washington's object was. The big animal lay bottom side up, vainly moving its flippers. In a few minutes Washington had killed the turtle and cut it out of the shell.

"Now we'll hab turtle soup!" he exclaimed.

Soon the fire was again blazing in the improvised stove, and a little later an appetizing smell filled the air. Washington had made the soup, and, in addition, had cooked a number of the turtle eggs.

Big clam shells again served for dishes and a better meal than the breakfast was served.

"Now if we only had some dessert," spoke Mr. Henderson in a joking tone, "we wouldn't want much more. But I suppose dessert is out of the question."

Jack and Mark looked at each other and, without a word went off toward the woods. In a little while they came back, their arms filled with cocoanuts.

"How will these do for dessert?" asked Jack.

"Fine!" cried Mr. Henderson.

The fruit was broken open with stones and the delicious milk and soft pulp eaten with much relish. Then the adventurers stretched out beneath the trees and rested. The thoughts of each one were busy with plans for recovering the submarine, though no one seemed to be able to suggest any thing.

It was getting dusk, when, somewhat discouraged over the result of the visit of the savages, they were all seated on the beach. They were beginning to think again of something to eat when Andy Sudds, discovered the long black box which Washington had brought with him in his flight from the Porpoise, and dropped in a hollow.

"I suppose you've got something very fine in there, Washington?"

"I declare to goodness I don't know what dat air contraption am conglomerated with," said the colored man. "I jest grabbed it up and run."

The old hunter had, in the meanwhile, taken the cover off.

"What in the world have we struck," he exclaimed.

"Sky rockets!" cried Jack, with a glance at the contents of the box.

"Yes," said Professor Henderson. "I took some aboard in case we might have to signal for help on the water."

"Hurrah!" yelled Andy.

"What's the matter?" asked Jack.

"We'll use the sky rockets as weapons against the natives!" shouted the old hunter, capering about on the sand.



CHAPTER XIX

REGAINING THE SHIP

At first the others did not know what he meant. Andy seemed much excited, and for a time the professor thought the heat and worry might have affected the hunter's mind.

"We'll show 'em a thing or two!" cried Andy. "I once scared a lot of Indians this way so they didn't know whether they were on their head or their feet. Hurrah!"

"What are you talking about?" asked Mr. Henderson. "Hadn't you better sit down and rest a bit?"

"I'm all right," replied Andy. "I'm talking about those sky rockets. They'll be better than bullets. You see," he went on, "after it gets dark we'll shoot the rockets over the ship. The savages will think they are in the midst of a lot of falling stars, and if they don't take to their boats and leave us the ship I'll miss my guess, that's all."

"Good!" exclaimed the inventor. "We'll try it."

The rockets were taken out and examined. They were big affairs of several pound weight and were intended for far-off signalling at sea.

Andy, with the aid of the boys, Tom and Bill, soon constructed a rough sort of support from which to set off the fire-works. As soon as it grew dark, which it did about seven o'clock, preparations were made to try the experiment.

With a whizz and roar the first rocket went sailing skyward. Up through the black night it went, trailing behind it a shower of fire and sparks. Then, with a loud report like that of a gun it burst directly over the ship and a rain of brilliantly colored globes of flame descended.

"Shot number one!" cried Andy, who was setting off the rockets.

For a few seconds after the first flight there came no sound from the natives at the ship. Then, just as the second rocket was set off there issued a long-drawn howl, which was succeeded by cries of fear.

"We've waked 'em up!" shouted Jack.

In rapid succession several more rockets were sent over the Porpoise. By the light of them could be seen a mass of natives crowded out on the small deck, while others were in their canoes.

"I think I'll try it a little lower this time," remarked Andy. "Maybe I can hit some of 'em!"

He slanted the support closer to the ground and set off two rockets at once. Straight across the sandy beach they flew, directly toward the crowd of natives on the ship. Right into the midst of the savages the trailing comet of fire shot, with a hiss, roar and sputter that was enough to strike terror into the bravest heart.

There was a long piercing howl of fear. Then, as the natives felt the hot sparks scatter over their half-naked bodies, they broke into a wild stampede. Over the side of the ship they plunged, into the sea, and swam off. Those in boats paddled quickly away.

For good measure Andy sent another rocket into the midst of the fleeing ones, and this served to quicken their departure. By the light of the last one it could be seen that the ship was deserted, though the water all about her was black with the swimming savages, and the canoes.

"I guess they won't come back in a hurry!" cried Andy. "Come on! We'll board the ship now, and get the electric guns to ward off any further attacks!"

"That's the talk!" cried Mark.

Toward the Porpoise all started on a run. As they neared her they found that the rising tide had floated her.

"We must see if the natives damaged her," spoke Mr. Henderson as soon as he set foot on deck. "If they have it will be a hard matter to make repairs so far from civilization."

A hasty examination, however, showed that the savages had disturbed little. The engine was soon set in motion, and, in ten minutes the ship was steaming away from the coast, headed toward the south, the goal they were so eagerly seeking.

As soon as they were well out to sea, and all sight of the canoes of the savages had been lost, supper was served, and all brought good appetites to the table. For, though the improvised meals on shore had tasted good, there had not been much to them.

For several days the Porpoise was kept on her course, sailing along under the water by day, and upon the surface at night. It was one pleasant afternoon, while Nellie, Jack and Mark were sitting out on the deck, during one of the times when the boat had risen to the surface to renew the air supply, that a strange commotion was observed off their lee. The ocean seemed to be boiling.

"What is that?" asked the little girl.

The two boys looked to where she pointed. Indeed the ocean seemed to be bubbling up and down in a strange manner.

"It's a school of porpoises," said Jack.

Just then the water became alive with big fish. They leaped over each other, springing high into the air and falling back into the sea with resounding splashes.

"They're not porpoises! They're whales! Baby whales!" yelled Mark. "Look out or some of the big ones may ram the boat!"

As he spoke the water all about the submarine was seen to be fairly swarming with the small whales. There were scores of them, and, at times, they were so thick that it appeared possible to walk out upon them without getting very deep into the water.

Suddenly the ship careened to one side and the sea rushed over the deck. It was evident that one of the big whales, which were deeper down in the water, had struck the vessel.

Nellie screamed and tried to grab the hand rail that was about the platform. She missed her grip. The next instant she was floundering in the ocean, in the midst of the school of whales.

"Man overboard!" yelled Jack, remembering vaguely that he had read this was the proper call to make in case of accident.

His cry brought Washington and the professor up the companionway on the jump.

"Launch the boat!" cried the inventor as he saw what had happened.

Mark was already in action. At the first sight of Nellie slipping over the side he had thrown off his coat, broken the laces of his shoes in order the more quickly to remove the foot coverings, and had dived into the swirling water which surrounded the submarine.

He struck out in the direction where the little girl had disappeared, and as her golden head appeared above the mass of foam he yelled in encouragement.

By this time the small boat was launched and the colored man and Jack were pulling toward him. Mark succeeded in reaching Nellie as she was going down the second time. He grabbed her long locks and managed to keep her up until the little craft was alongside of him.