IN THE MIDST OF FIRE

"Pull the secondary emergency lever!" cried the professor through the speaking tube to Washington. "We must reach the surface at once!"

"Are we damaged?" asked Andy, scrambling to his feet, for the shock had knocked him down. The professor had not fallen because he clung to the steering wheel.

The ship gave a sudden lurch.

"We're sinking!" cried Bill, rushing to the conning tower from the engine-room.

"That's only the action of one of the emergency levers," said the professor calmly. "It forces compressed air into the tanks the more quickly to empty them of water. I think we are safe."

"What is it?" asked Mark, as, followed by Jack, he came forward.

"We tried to do the torpedo act to one of Uncle Sam's ships," explained Andy.

The electric lights had been switched on, and, with the Porpoise flooded with the bright beams, those on board waited anxiously for what was to happen next.

Suddenly an upward motion was experienced. The next instant the craft bounced out of the water and fell back in a smother of foam, shaking and shivering, alongside a small armored warship that was anchored about two miles and a half from shore.

"Open the manhole," commanded Mr. Henderson.

A CURIOUS THRONG CROWDED TO THE RAIL OF THE WARSHIP.—Page 28.

Mark sprang up the iron ladder that led to the opening in the deck of the Porpoise and threw back the cams that held the heavy iron in place. Then he swung the cover back and stepped out on the small platform, followed by the professor, Andy and Jack. They looked up to find themselves observed by a curious throng that crowded to the rail of the warship.

"What are you trying to do? Ram me with a new-fangled torpedo?" asked an angry voice, and a man in a gold laced uniform, who, from his importance plainly showed himself to be the captain of the ship, shook his fist at Mr. Henderson.

"I might ask what right your ship has to get in my path," replied the inventor. "It was all an accident."

"Mighty queer," muttered the naval commander. "Looks very suspicious. How do I know but what you're a torpedo from some foreign nation?"

"Because this is not a torpedo," replied Mr. Henderson. "It is a new submarine boat of my invention, and I was giving it a trial spin."

"I guess you'd better come aboard and do your explaining," went on the captain. "I don't like the looks of things. Lower a boat!" he shouted, "and bring those chaps to my cabin. I want to question them."

It did not suit Professor Henderson to have his plans upset in this fashion. Nor did he care to give a detailed description of his ship to officers of the war department. He had many valuable inventions that were not patented. So he determined to outwit the pompous commander of the cruiser.

The noise made in preparing the small boat for lowering over the side of the big ship could be plainly heard.

"Go below, all of you, and as quietly as you can," whispered Mr. Henderson.

Andy, Mark and Jack obeyed. At that instant the side of the warship was almost deserted, for the sailors who had gathered to observe the Porpoise had gone to lower the small boat.

No sooner had Jack, who was in the rear, disappeared through the manhole than the professor, with a quick jump, followed him.

"Here! Come back!" shouted the warship's captain as he saw Mr. Henderson's head disappearing from view. "Come back I say!"

But with a quick movement the inventor pulled down the manhole cover and clamped it. Then he sprang to the conning tower, and, with a jerk, opened the levers that admitted water to the tanks. The Porpoise began to sink slowly, and then more suddenly, so that, in less than a minute, she was out of sight beneath the waves, and the angry, gold-laced captain was staring in wonderment at the place where the submarine had been. The spot was marked only by a few bubbles and some foam.

"I guess he'll wait some time for an explanation," spoke Mr. Henderson, as he started the big screw and sent the Porpoise ahead at a swift pace.

"That was rather a narrow escape," observed Jack, standing at the foot of the conning tower stairs and talking to Andy and Mr. Henderson, who was steering.

"It certainly was," agreed the professor. "I have not yet become used to seeing things very far ahead in the dimness caused by being under water. But we'll soon get used to it. Luckily, the Porpoise was not damaged by the shock."

For several hours the Porpoise was kept on her course. She behaved handsomely, and nothing excepting slight and easily remedied defects were found. The professor steered well out to sea, increasing both the forward speed and the depth to which the vessel sank. Presently the craft came to a stop with a little jolt.

"What's the trouble?" asked Mark, somewhat alarmed.

"Nothing at all," replied the professor with a smile, as he stepped out of the conning tower and entered the engine-room. "I thought it was time for dinner so I stopped the ship. We are now resting on the ocean bed, about half a mile below the surface. Look!"

As he spoke he slid back the slides covering the plate glass windows. The boys saw that the ship rested in the midst of an immense forest of sea weed. Some of the stalks were as large around as trees. In and out among the snake-like, waving branches swam big fishes. It was a weird, but beautiful sight.

"Come, Washington, serve dinner," ordered Mr. Henderson, and the colored man soon had a good meal prepared. Few repasts have been eaten under such strange circumstances.

Desiring to be back at his secluded dock by nightfall, Captain Henderson soon started the Porpoise up again. Without any accidents the return trip was made and by nine o'clock the Porpoise rode safely at the dock where she had been launched.

The night was spent in the cabin on shore. Early the next morning Mr. Henderson paid a visit to the ship, to make a thorough examination by daylight, and see if the craft had suffered any damage.

"I think you and Mark will have to make a trip to town," he said to Jack at the breakfast table. "I need a new monkey wrench and some other tools and some small pieces of machinery. I'll give you a list of them, and you can bring them back in a valise, for they will be quite numerous."

After the meal the inventor made a record of what he needed and the boys started off.

"In case the machine shop does not have everything and you have to wait for something, you had better stay in the town all night," the captain of the Porpoise said. "It is quite a long trip and I don't want you traveling after dark. Put up at the hotel if you are delayed."

Provided with money for their purchase, and a large valise in which to carry them, the boys started off. They had to walk two miles to where a trolley line was built that ran to the town of Easton, where they were to get the tools and parts of machinery.

They made the trip safely and without incident. When they gave the machinist, to whom they had been directed by Mr. Henderson, the list of the things needed, the man looked puzzled.

"I'll have to make one piece," he said. "You'll have to wait for it. Can't promise it before to-morrow morning about eight o'clock."

"That will be all right," remarked Mark. "We'll call for it then."

So, bearing in mind Mr. Henderson's instructions, the boys engaged a room at the hotel, which was quite a large one, for Easton was a favorite summer resort and the town was filled with visitors. The lads strolled about the town, had their dinner, and then went for a bath in the surf. They retired early, for they were tired.

In the middle of the night Mark began to dream that he was on board the Porpoise and that the submarine blew up. There was a loud noise, he saw a bright flash of flame, and saw rolling clouds of smoke. So vivid was the vision that he thought he tried to leap out of the boat, and awoke with a jump, to find Jack shaking him.

"What's the matter?" inquired Mark.

"The hotel's on fire!" shouted Jack.

Mark sprang out of bed and with Jack rushed to the window, for their room was filled with thick smoke. They could see the dull glare of flames, which every moment were becoming brighter.

The next instant a loud explosion shook the building. It swayed and seemed likely to topple over. Outside the boys could hear excited shouts and the puffing and whistling of fire engines.

"Quick! Run!" yelled Mark. He opened the door leading into the corridor, but was driven back by a rush of flames and smoke that almost stifled him.

"We must try the fire escape!" shouted Mark.

"Don't forget the valise with the tools;" exclaimed Jack, and Mark hastened to where he had placed it under the bed.

Then the two boys rushed to the balcony on which their front windows opened, and whence the fire escapes led down to the streets. The lads had only time to slip on their coats, trousers, shoes and caps.

As they were preparing to clamber down the iron ladders they heard someone on the balcony next to them shout:

"Here, you boys! Stop! I want you!"