Chapter Twelve
For a Breath of Air
They could hardly realize it, yet the depth-gage told the story. Itregistered a distance below the surface of the ocean of five thousandseven hundred feet--a little over a mile. The Advance had actually cometo rest on the bottom of the Atlantic.
"Hurrah!" cried Tom. "Let's get on the diving suits, dad, and walkabout on land under water for a change."
"No," said Mr. Swift soberly. "We will hardly have time for that now.Besides, the suits are not yet fitted with the automatic air-tanks, andwe can't use them. There are still some things to do before we start onour treasure cruise. But I want to see how the plates are standingthis pressure."
The Advance was made with a triple hull, the spaces between the layersof plates being filled with a secret material, capable of withstandingenormous pressure, as were also the plates themselves. Mr. Swift, aidedby Mr. Jackson and Captain Weston, made a thorough examination, andfound that not a drop of water had leaked in, nor was there the leastsign that any of the plates had given way under the terrific strain.
"She's as tight as a drum, if you will allow me to make thatcomparison," remarked Captain Weston modestly. "I couldn't ask for adryer ship."
"Well, let's take a look around by means the searchlight and theobservation windows, and then we'll go back," suggested Mr. Swift. "Itwill take about two days to get the stores and provisions aboard andrig up the diving suits; then we will start for the sunken treasure."
There were several powerful searchlights on the Advance, so arrangedthat the bow, stern or either side could be illuminated independently.There were also observation windows near each light.
In turn the powerful rays were cast first at the bow and then aft. Inthe gleams could be seen the sandy bed of the ocean, covered withshells of various kinds. Great crabs walked around on their long,jointed legs, and Tom saw some lobsters that would have brought joy tothe heart of a fisherman.
"Look at the big fish!" cried Mr. Damon suddenly, and he pointed tosome dark, shadowy forms that swam up to the glass windows, evidentlypuzzled by the light.
"Porpoises," declared Captain Weston briefly, "a whole school of them."
The fish seemed suddenly to multiply, and soon those in the submarinefelt curious tremors running through the whole craft.
"The fish are rubbing up against it," cried Tom. "They must think wecame down here to allow them to scratch their backs on the steelplates."
For some time they remained on the bottom, watching the wonderful sightof the fishes that swam all about them.
"Well, I think we may as well rise," announced Mr. Swift, after theyhad been on the bottom about an hour, moving here and there. "We didn'tbring any provisions, and I'm getting hungry, though I don't know howthe others of you feel about it."
"Bless my dinner-plate, I could eat, too!" cried Mr. Damon. "Go up, byall means. We'll get enough of under-water travel once we start for thetreasure."
"Send her up, Tom," called his father. "I want to make a few notes onsome needed changes and improvements."
Tom entered the lower pilot house, and turned the valve that opened thetanks. He also pulled the lever that started the pumps, so that thewater ballast would be more quickly emptied, as that would render thesubmarine buoyant, and she would quickly shoot to the surface. To thesurprise of the lad, however, there followed no outrushing of thewater. The Advance remained stationary on the ocean bed. Mr. Swiftlooked up from his notes.
"Didn't you hear me ask you to send her up, Tom?" he inquired mildly.
"I did, dad, but something seems to be the matter," was the reply.
"Matter? What do you mean?" and the aged inventor hastened to where hisson and Captain Weston were at the wheels, valves and levers.
"Why, the tanks won't empty, and the pumps don't seem to work."
"Let me try," suggested Mr. Swift, and he pulled the various handles.There was no corresponding action of the machinery.
"That's odd," he remarked in a curious voice "Perhaps something hasgone wrong with the connections. Go look in the engine-room, and askMr. Sharp if everything is all right there."
Tom made a quick trip, returning to report that the dynamos, motors andgas engine were running perfectly.
"Try to work the tank levers and pumps from the conning tower,"suggested Captain Weston. "Sometimes I've known the steam steering gearto play tricks like that."
Tom hurried up the circular stairway into the tower. He pulled thelevers and shifted the valves and wheels there. But there was noemptying of the water tanks. The weight and pressure of water in themstill held the submarine on the bottom of the sea, more than a milefrom the surface. The pumps in the engine-room were working at topspeed, but there was evidently something wrong in the connections. Mr.Swift quickly came to this conclusion.
"We must repair it at once," he said. "Tom, come to the engine-room.You and I, with Mr. Jackson and Mr. Sharp, will soon have it in shapeagain."
"Is there any danger?" asked Mr. Damon in a perturbed voice. "Bless mysoul, it's unlucky to have an accident on our trial trip."
"Oh, we must expect accidents," declared Mr. Swift with a smile. "Thisis nothing."
But it proved to be more difficult than he had imagined to re-establishthe connection between the pumps and the tanks. The valves, too, hadclogged or jammed, and as the pressure outside the ship was so great,the water would not run out of itself. It must be forced.
For an hour or more the inventor, his son and the others, worked away.They could accomplish nothing. Tom looked anxiously at his parent whenthe latter paused in his efforts.
"Don't worry," advised the aged inventor. "It's got to come rightsooner or later."
Just then Mr. Damon, who had been wandering about the ship, entered theengine-room.
"Do you know," he said, "you ought to open a window, or something."
"Why, what's the matter?" asked Tom quickly, looking to see if the oddman was joking.
"Well, of course I don't exactly mean a window," explained Mr. Damon,"but we need fresh air."
"Fresh air!" There was a startled note in Mr. Swift's voice as herepeated the words.
"Yes, I can hardly breathe in the living-room, and it's not much betterhere."
"Why, there ought to be plenty of fresh air," went on the inventor. "Itis renewed automatically."
Tom jumped up and looked at an indicator. He uttered a startled cry.
"The air hasn't been changed in the last hour!" he exclaimed. "It isbad. There's not enough oxygen in it. I notice it, now that I'vestopped working. The gage indicates it, too. The automatic air-changermust have stopped working. I'll fix it."
He hurried to the machine which was depended on to supply fresh air tothe submarine.
"Why, the air tanks are empty!" the young inventor cried. "We haven'tany more air except what is in the ship now!"
"And we're rapidly breathing that up," added Captain Weston solemnly.
"Can't you make more?" cried Mr. Damon. "I thought you said you couldmake oxygen aboard the ship."
"We can," answered Mr. Swift, "but I did not bring along a supply ofthe necessary chemicals. I did not think we would be submerged longenough for that. But there should have been enough in the reserve tankto last several days. How about it, Tom?"
"It's all leaked out, or else it wasn't filled," was the despairinganswer. "All the air we have is what's in the ship, and we can't makemore."
The treasure-seekers looked at each other. It was an awful situation.
"Then the only thing to do is to fix the machinery and rise to thesurface," said Mr. Sharp simply. "We can have all the air we want,then."
"Yes, but the machinery doesn't seem possible of being fixed," spokeTom in a low voice.
"We must do it!" cried his father.
They set to work again with fierce energy, laboring for their verylives. They all knew that they could not long remain in the shipwithout oxygen. Nor could they desert it to go to the surface, for themoment they le
ft the protection of the thick steel sides the terriblepressure of the water would kill them. Nor were the diving suitsavailable. They must stay in the craft and die a miserable death--unlessthe machinery could be repaired and the Advance sent to the surface.The emergency expanding lifting tank was not yet in working order.
More frantically they toiled, trying every device that was suggested tothe mechanical minds of Tom, his father, Mr. Sharp or Mr. Jackson, tomake the pumps work. But something was wrong. More and more foul grewthe air. They were fairly gasping now. It was difficult to breathe, tosay nothing of working, in that atmosphere. The thought of theirterrible position was in the minds of all.
"Oh, for one breath of fresh air!" cried Mr. Damon, who seemed tosuffer more than any of the others. Grim death was hovering aroundthem, imprisoned as they were on the ocean's bed, over a mile from thesurface.