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Twenty Thousand Leagues Under the Sea
Chapter 12. SOME FIGURES
A moment later, we were seated on a divan in the saloon, smoking.
The Captain showed me a sketch that gave the plan, section, and height of the Nautilus.
Then he began his description with these words,
"Here, M".
Aronnax, are the different sizes of the boat you're in.
It's a long cylinder with cone-shaped ends.
It's very like a cigar in shape, a shape already used in London in several ships of the same kind.
The length of this cylinder, from front to back, is exactly 232 feet, and its widest point is twenty-six feet.
It's not built quite like your long-voyage steamers.
Its lines and curves are long and extended enough to let the water slide off easily and not block its passage.
These two sizes let you find out, by a simple calculation, the surface and cubic space of the Nautilus.
Its area measures 6032 feet, and its space is about 1500 cubic yards.
That means, when it's completely underwater, it pushes aside 50,000 feet of water, or weighs 1500 tons.
"When I made the plans for this submarine vessel, I meant for nine-tenths of it to be underwater".
So it should only push aside nine-tenths of its size, which means it should only weigh that number of tons.
I shouldn't have gone over that weight, building it with the sizes I mentioned.
"The Nautilus is made of two hulls, one inside and one outside, joined by T-shaped iron pieces, which make it very strong".
In fact, because of this cell-like design, it resists like a solid block.
Its sides can't bend, it holds together naturally, not just because of its rivets.
And the sameness of its construction, due to the perfect union of the materials, lets it face the roughest seas.
"These two hulls are made of steel plates, whose density is from .7 to .8 that of water."
"The first one isn't less than two and a half inches thick and weighs 394 tons."
"The second covering, the keel, twenty inches high and ten thick, weighs sixty-two tons by itself."
"The engine, the ballast, the different extras and equipment, the partitions and walls, weigh 961.62 tons."
"Do you follow all this?"
"I do."
"Then, when the Nautilus floats under these conditions, one-tenth is out of the water."
"Now, if I've made tanks equal to this tenth, able to hold 150 tons, and I fill them with water, the boat will weigh 1507 tons."
"It will then be completely underwater".
"That would happen, Professor."
"These tanks are in the lower parts of the Nautilus."
"I turn on taps and they fill, and the vessel sinks that had just been level with the surface."
"Well, Captain, but now we come to the real difficulty."
"I can understand your rising to the surface."
But diving below the surface, doesn't your submarine face pressure, an upward push of one atmosphere per thirty feet of water, about fifteen pounds per square inch?
"Just so, sir."
"Then, unless you completely fill the Nautilus, I don't see how you can pull it down to those depths."
"Professor, you mustn't confuse statics with dynamics, or you'll make serious mistakes."
"There's very little effort needed to reach the lower parts of the ocean, because all bodies have a tendency to sink."
"When I wanted to find out the extra weight needed to sink the Nautilus, I only had to calculate the reduction in volume that seawater gets according to the depth."
"That's clear."
"Now, if water isn't completely impossible to compress, it's at least able to be compressed very slightly".
In fact, after the most recent calculations, this reduction is only .000436 of an atmosphere for each thirty feet of depth.
If we want to sink 3000 feet, I should keep track of the reduction in size.
This reduction is under pressure equal to that of a column of water of a thousand feet.
The calculation is easy to check, Now, I have extra tanks that can hold a hundred tons.
So I can sink to a good depth.
I want to rise to the level of the sea, I only let out the water.
If I want the Nautilus to come out of the tenth part of its total space, I empty all the tanks.
I had nothing to argue against these ideas.
"I accept your calculations, Captain," I replied.
"I'd be wrong to argue with them since daily experience confirms them. But I see a real difficulty in the way."
"What's it, sir?"
"When you're about 1000 feet deep, the walls of the Nautilus bear a pressure of 100 atmospheres."
"If you empty the extra tanks now, the vessel will lighten and rise to the surface."
"The pumps must overcome a pressure of 100 atmospheres, which is 1500 pounds per square inch."
"From that, a power."
"That electricity alone can give," said the Captain quickly.
"I repeat, sir, that the dynamic power of my engines is almost endless."
"The pumps of the Nautilus have an enormous power, as you must have seen when their jets of water burst like a flood onto the Abraham Lincoln."
"Besides, I use extra tanks only to reach a middle depth of 750 to 1000 fathoms, and that's to manage my machines."
"Also, when I want to visit the depths of the ocean five or six miles below the surface, I use slower but no less certain methods."
"What are they, Captain?"
"That means I have to tell you how the Nautilus works."
"I'm eager to learn."
I use an ordinary rudder fixed on the back of the stern-post to steer this boat.
I turn to starboard or port by following a flat plan.
One wheel and some ropes help me steer.
But I can also make the Nautilus rise and sink by a vertical movement.
This uses two slanted planes fastened to its sides, opposite the center of floating.
These planes move in every direction, and they're worked by strong levers from the inside.
If the planes are kept parallel with the boat, it moves flat.
If slanted, the Nautilus, according to this slant, and under the influence of the screw, either sinks diagonally or rises diagonally as it suits me.
"And even if I want to rise more quickly to the surface, I stop the screw."
"Then the pressure of the water causes the Nautilus to rise straight up like a balloon filled with hydrogen".
"Bravo, Captain! But how can the steersman follow the route in the middle of the waters?"
"The steersman is placed in a glass box that's raised above the hull of the Nautilus and fitted with lenses."
"Are these lenses able to resist such pressure?"
"Perfectly."
"Glass can break from a blow, but still offers considerable resistance."
"In 1864 fishing experiments in the Northern Seas, plates under one-third inch resisted sixteen atmospheres, and the glass I use is at least thirty times thicker."
"Granted. But, after all, to see, the light must beat the darkness, and in the middle of the darkness in the water, how can you see?"
"Behind the steersman's cage is placed a powerful electric reflector, whose rays light up the sea for half a mile in front."
"Ah! Bravo, bravo, Captain! Now I can explain that phosphorescence in the supposed narwhal that puzzled us so."
"I now ask you if the boarding of the Nautilus and the Scotia, which caused so much noise, was the result of a chance meeting"?
"Quite accidental, sir. I was sailing only one fathom below the surface of the water when the shock came. It had no bad result."
"None, sir. But now, about your meeting with the Abraham Lincoln?"
"Professor, I'm sorry for one of the best vessels in the American navy."
"But they attacked me, and I had to defend myself."
"I only made the frigate unable to fight."
"She won't have any trouble getting repaired at the next port."
"Ah, Commander! Your Nautilus is certainly a wonderful boat."
"Yes, Professor," said Captain.
"I love it as if it were part of myself."
"If danger threatens one of your vessels on the ocean, the first feeling is of an abyss above and below."
"On the Nautilus, men's hearts never fail them."
"There are no defects or rigging, no sails the wind can carry away, and no boilers to burst or fire to fear."
"It is made of iron, not wood, so no fire, electricity is the only mechanical agent, and it never needs coal."
"But how could you build this wonderful Nautilus in secret?"
"Each separate part, M."
"Aronnax, was brought from different parts of the world."
"The keel was made at Creusot."
"The shaft of the screw at Penn and Company's in London."
"The iron plates of the hull at Laird's in Liverpool."
"The screw itself at Scott's in Glasgow."
"The tanks were made by Cail and Company in Paris."
"The engine by Krupp in Prussia."
"Its beak in Motala's workshop in Sweden."
"Its math instruments by Hart Brothers of New York, and so on."
"And each of these people had my orders under different names."
"But these parts had to be put together and arranged?"
"Professor, I set up my workshops on a desert island in the ocean."
"There my workmen, that's, the brave men that I taught and trained, and I myself put together our Nautilus."
"Then when the work was finished, fire destroyed all trace of our work on this island, which I could have jumped over if I'd liked."
"Then the cost of this vessel is great?"
"M. Aronnax, an iron vessel costs 45 pounds per ton, and the Nautilus weighed 1500, so it cost 67,500 pounds."
"With 80,000 more for fitting and about 200,000 including works of art and the collections, the cost was much higher".
"One last question, Captain Nemo."
"Ask it, Professor."
"You're rich?"
"Immensely rich, sir. And I could, without missing it, pay the national debt of France."
I stared at the strange person who spoke like this.
Was he playing with my trust? The future would decide that.