In his horror, Clifford forgot himself and shouted wildly to Frank, but the young inventor did not reply.

Of course he could not hear. Indeed, the only way conversation could be carried on was by placing the helmets closely together and loudly shouting.

So that the young inventor, intent on examining the Dolphin’s position, thought of nothing else, until by chance he turned his head.

Then the sight which he beheld filled him with horror.

For a moment he could not act.

“My God!” he gasped, “Clifford is lost!”

Then his senses returned.

He realized that his friend was in mortal peril, and that he must go to his aid. At any cost he must try and save him.

So he drew his ax from his girdle and made a leap forward.

In the meanwhile Clifford had been fighting for all that was in his power. He wielded his ax with desperate energy.

He struck blow after blow at the huge tentacle which held him so firmly. Each blow threatened to sever it.

But even as success was crowning his efforts, out darted another arm and encircled him.

This was surely drawing him into the orifice, when Frank came to the rescue.

The young inventor dealt a terrific blow at the tentacle. It partly severed it. Another huge arm came stealing out, and Frank dealt it a blow also.

Clifford was too exhausted to do more. But Frank threw an arm about him, and dealing the tentacle a severing blow drew his friend quickly out of reach.

Nothing more was seen of the octopus.

It did not emerge from its den, but a dense cloud of black fluid did, and it so clouded the water that Frank was obliged to drag Clifford some distance away.

The latter recovered quickly. Frank put his helmet close and shouted:

“Are you all right?”

“Yes,” replied Clifford; “it was a close call!”

“Indeed it was!”

“But for you I should have lost my life!”

Frank made signs to return to the Dolphin, but Clifford felt sufficient curiosity to ask:

“How about the boat?”

“There is but one way to get her off the reef.”

20“And that——”

“I will explain when we get back to the boat.”

“All right!”

In a few moments they reached the rail. To their surprise they saw Barney in the vestibule, all in his diver’s suit.

The brave Celt had seen their distress and was coming to their rescue.

“Begorra, Misther Frank!” he cried, when the two divers were once more safely aboard. “I thought it was the end av yez. May the Howly Vargin be praised, yez are all roight an’ safe!”

“Well; I thought our friend, Clifford, was surely done for,” said Frank, “but by the best of good fortune he is still with us.”

“Which happy fact I owe to Mr. Reade,” declared Clifford. “I shall never forget it.”

The matter was dropped now, however, for another important one. The question as to the fate of the Dolphin was now brought up.

Frank was thoughtful for some while, and finally said:

“Wait until to-morrow. Then I will be able to decide.”

That night few in the party slept very soundly; at an early hour Pomp had a steaming breakfast ready.

All were rather sober as they sat around the table.

“Well,” said Frank, “if we are doomed to spend the rest of our days at the bottom of the sea we can count upon extending our span of life to a limit of about two years.”

“How do you make that exact calculation?” asked Captain Hartley.

“There are just stores enough on board to last two years,” replied Frank.

“After they are gone?”

Frank laughed nervously.

“Two years is a good long while in which to make up our minds what to do. Perhaps before that time we may hit upon a good scheme.”

“Let us hope so,” said Clifford; “but we should like to hear of your scheme of yesterday, Frank.”

“By all means!” cried Hartley.

“Huh! neber you mind,” cried Pomp. “Marse Frank he neber get stuck. He fin’ some way out ob any kin’ ob a scrape.”

“Bejabers, that’s roight!” averred Barney.

After some reflection and much persuasion Frank divulged the plan which had occurred to him.

“It is a simple one,” he said; “it consists merely of digging a mine under the boat and trying to dislodge her with dynamite.”

21“Hurrah!” cried Clifford. “What could be better?”

“So say I!” said Hartley.

But Frank shook his head slowly.

“There are many risks involved,” he said. “We must consider the possibility of the Dolphin springing a leak, or of the dynamite straining her timbers.”

“But—how can she spring a leak?”

“Her timbers or plates may be already started, and dislodging her may start the leak in an instant.”

The faces of all fell.

“Is there any certainty of such being the case?” asked Hartley.

“No certainty,” replied Frank, “only a possibility, and a very strong one at that.”

“Then it is narrowed down to a question of expediency, whether it is better to risk instant death or the more lingering fate of two years under the deep sea.”

“Exactly,” agreed Frank. “If we explode the dynamite now the boat may fill and sink in ten minutes. There is the chance.”

“Humph!” said Hartley. “If we have got to die it may as well be now as two years from now.”

Frank glanced around the little circle inquiringly.

“What do the rest of you say?” he asked. “Shall we accept the chance?”

“Put it to ballot,” said Hartley.

“Agreed!”

Clifford made out some ballots and handed them around. They were marked and thrown on the table.

Hartley counted them.

His face wore an indescribable expression as he looked up and said:

“The question is settled. The ballot is unanimous.”

“In favor of——”

“The dynamite.”

Frank Reade, Jr., arose from his chair. He was very cool and steady as he said to Barney:

“Bring up the metal canisters from the hold. Rig a wire with the battery. Then procure picks and spades, put on your suits, you and Pomp, and come with me.”

Pomp went for the picks and spades. In a few moments all was in readiness.

Frank, with Barney and Pomp, donned diving suits.

Then they went out on deck, and a little later were at the keel of the boat.

Frank directed the digging of the mine.

The coral was easily picked away, but the ledge rock required drilling and splitting.

22Slowly but surely the mine was made. All that day the work went on.

It was noon of the succeeding day, however, before it was finished. Then the cartridges were placed.

Great bales, made of soft burlap filled with sand, were placed under the keel and over the dynamite to act as a cushion and reduce the shock.

Then the wires were connected, and the three divers went aboard the Dolphin.

They removed their diving suits, and Frank faced Clifford and Hartley, who were pale and somewhat excited.

Now that the critical moment had come, each really shrank from the mighty risk. Yet neither could justly be called a coward.

“Well?” said Hartley.

“Well!” exclaimed Clifford.

Then there was a period of silence. Frank looked keenly at the two men.

“What shall it be?” he asked. “I shall leave it all with you.”

“Do not hesitate on our account,” said Hartley firmly; “we do not shrink from it.”

“All will be over in a very few moments. We shall know if it is to be life or death.”

“It would be death in the long run anyway,” declared Clifford. “Whatever it is, let us all meet our fate like brave men.”

“That settles it,” declared Frank, “prepare for the shock!”

Everything movable aboard the boat was carefully secured. Then Frank announced all in readiness.

It was a moment of suspense.

Frank stood by the vestibule door with the wire and electric key in his hand. He closed his eyes and spasmodically pressed it.

It was all a matter of momentous doubt. All hinged upon the result of the explosion. Five human lives hung in the balance.

The result was instantaneous.

All that the voyagers could ever remember of the affair afterward was that there was a terrific shock, a confused jumbling of ideas and incidents, and then——

Frank Reade, Jr., opened his eyes and looked about him.

Wonder of wonders!

It was broad daylight.

They were on the surface of the sea. All about them was one heaving expanse of blue.

“Great whales!” cried Captain Hartley. “What sort of a transformation do you call this, mates?”

23“We are saved!” cried Clifford.

“Begorra, it’s on the surface we are,” averred Barney. “Howiver did this happen?”

“Huh! Don’ yo’ know, I’ish?” cried Pomp. “Yo’ done lef de switch ob de reservoir turned on.”

“Bejabers that’s thrue!” cried the Celt. “I shure fergot it.”

“It’s all right!” cried Frank; “it helped the explosion to raise the boat. Now it is only a question as to whether the boat leaks or not.”

“How shall we find out?”

“We will sink if she does,” laughed Frank; “but I think we could hear the water coming in if such was the case.”

With which Frank went below. He listened at the bulkheads leading into the hold.

But the boat seemed as buoyant as ever. There was not the slightest indication that she was leaking.

The spirits of all now waxed more cheerful. It was a moral certainty that the boat was saved and their lives as well.

But as this realization fully dawned upon them, a loud cry came from Pomp.

“Hi, dar! luk out or we be run down, Marse Frank!”