the same sort. The length of this cylinder, from stem to stern, is

exactly 232 feet, and its maximum breadth is twenty-six feet. It is

not built quite like your long-voyage steamers, but its lines are

sufficiently long, and its curves prolonged enough, to allow the water

to slide off easily, and oppose no obstacle to its passage. These two

dimensions enable you to obtain by a simple calculation the surface and

cubic contents of the Nautilus. Its area measures 6,032 feet; and its

contents about 1,500 cubic yards; that is to say, when completely

immersed it displaces 50,000 feet of water, or weighs 1,500 tons.



"When I made the plans for this submarine vessel, I meant that

nine-tenths should be submerged: consequently it ought only to

displace nine-tenths of its bulk, that is to say, only to weigh that

number of tons. I ought not, therefore, to have exceeded that weight,

constructing it on the aforesaid dimensions.



"The Nautilus is composed of two hulls, one inside, the other outside,

joined by T-shaped irons, which render it very strong. Indeed, owing

to this cellular arrangement it resists like a block, as if it were

solid. Its sides cannot yield; it coheres spontaneously, and not by

the closeness of its rivets; and its perfect union of the materials

enables it to defy the roughest seas.



"These two hulls are composed of steel plates, whose density is from .7

to .8 that of water. The first is not less than two inches and a half

thick and weighs 394 tons. The second envelope, the keel, twenty

inches high and ten thick, weighs only sixty-two tons. The engine, the

ballast, the several accessories and apparatus appendages, the

partitions and bulkheads, weigh 961.62 tons. Do you follow all this?"



"I do."



"Then, when the Nautilus is afloat under these circumstances, one-tenth

is out of the water. Now, if I have made reservoirs of a size equal to

this tenth, or capable of holding 150 tons, and if I fill them with

water, the boat, weighing then 1,507 tons, will be completely immersed.

That would happen, Professor. These reservoirs are in the lower part

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,

does not your submarine contrivance encounter a pressure, and

consequently undergo an upward thrust of one atmosphere for every

thirty feet of water, just about fifteen pounds per square inch?"



"Just so, sir."



"Then, unless you quite fill the Nautilus, I do not see how you can

draw it down to those depths."



"Professor, you must not confound statics with dynamics or you will be

exposed to grave errors. There is very little labour spent in

attaining the lower regions of the ocean, for all bodies have a

tendency to sink. When I wanted to find out the necessary increase of

weight required to sink the Nautilus, I had only to calculate the

reduction of volume that sea-water acquires according to the depth."



"That is evident."



"Now, if water is not absolutely incompressible, it is at least capable

of very slight compression. Indeed, after the most recent calculations

this reduction is only .000436 of an atmosphere for each thirty feet of

depth. If we want to sink 3,000 feet, I should keep account of the

reduction of bulk under a pressure equal to that of a column of water

of a thousand feet. The calculation is easily verified. Now, I have

supplementary reservoirs capable of holding a hundred tons. Therefore

I can sink to a considerable depth. When I wish to rise to the level

of the sea, I only let off the water, and empty all the reservoirs if I

want the Nautilus to emerge from the tenth part of her total capacity."



I had nothing to object to these reasonings.



"I admit your calculations, Captain," I replied; "I should be wrong to

dispute them since daily experience confirms them; but I foresee a real

difficulty in the way."



"What, sir?"



"When you are about 1,000 feet deep, the walls of the Nautilus bear a

pressure of 100 atmospheres. If, then, just now you were to empty the

supplementary reservoirs, to lighten the vessel, and to go up to the

surface, the pumps must overcome the pressure of 100 atmospheres, which

is 1,500 lbs. per square inch. From that a power----"



"That electricity alone can give," said the Captain, hastily. "I

repeat, sir, that the dynamic power of my engines is almost infinite.

The pumps of the Nautilus have an enormous power, as you must have

observed when their jets of water burst like a torrent upon the Abraham

Lincoln. Besides, I use subsidiary reservoirs only to attain a mean

depth of 750 to 1,000 fathoms, and that with a view of managing my

machines. Also, when I have a mind to visit the depths of the ocean

five or six mlles below the surface, I make use of slower but not less

infallible means."



"What are they, Captain?"



"That involves my telling you how the Nautilus is worked."



"I am impatient to learn."



"To steer this boat to starboard or port, to turn, in a word, following

a horizontal plan, I use an ordinary rudder fixed on the back of the

stern-post, and with one wheel and some tackle to steer by. But I can

also make the Nautilus rise and sink, and sink and rise, by a vertical

movement by means of two inclined planes fastened to its sides,

opposite the centre of flotation, planes that move in every direction,

and that are worked by powerful levers from the interior. If the

planes are kept parallel with the boat, it moves horizontally. If

slanted, the Nautilus, according to this inclination, and under the

influence of the screw, either sinks diagonally or rises diagonally as

it suits me. And even if I wish to rise more quickly to the surface, I

ship the screw, and the pressure of the water causes the Nautilus to

rise vertically 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 glazed box, that is raised about the hull

of the Nautilus, and furnished with lenses."



"Are these lenses capable of resisting such pressure?"



"Perfectly. Glass, which breaks at a blow, is, nevertheless, capable

of offering considerable resistance. During some experiments of

fishing by electric light in 1864 in the Northern Seas, we saw plates

less than a third of an inch thick resist a pressure of sixteen

atmospheres. Now, the glass that I use is not less than thirty times

thicker."



"Granted. But, after all, in order to see, the light must exceed the

darkness, and in the midst of the darkness in the water, how can you

see?"



"Behind the steersman's cage is placed a powerful electric reflector,

the rays from which light up the sea for half a mile in front."



"Ah! bravo, bravo, Captain! Now I can account for this phosphorescence

in the supposed narwhal that puzzled us so. I now ask you if the

boarding of the Nautilus and of the Scotia, that has made such a noise,

has been the result of a chance rencontre?"



"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 rencontre with the Abraham Lincoln?"



"Professor, I am sorry for one of the best vessels in the American

navy; but they attacked me, and I was bound to defend myself. I

contented myself, however, with putting the frigate hors de combat; she

will not have any difficulty in getting repaired at the next port."



"Ah, Commander! your Nautilus is certainly a marvellous boat."



"Yes, Professor; and I love it as if it were part of myself. If danger

threatens one of your vessels on the ocean, the first impression is the

feeling of an abyss above and below. On the Nautilus men's hearts

never fail them. No defects to be afraid of, for the double shell is

as firm as iron; no rigging to attend to; no sails for the wind to

carry away; no boilers to burst; no fire to fear, for the vessel is

made of iron, not of wood; no coal to run short, for electricity is the

only mechanical agent; no collision to fear, for it alone swims in deep

water; no tempest to brave, for when it dives below the water it

reaches absolute tranquillity. There, sir! that is the perfection of

vessels! And if it is true that the engineer has more confidence in

the vessel than the builder, and the builder than the captain himself,

you understand the trust I repose in my Nautilus; for I am at once

captain, builder, and engineer."



"But how could you construct this wonderful Nautilus in secret?"



"Each separate portion, M. Aronnax, was brought from different parts of

the globe."



"But these parts had to be put together and arranged?"



"Professor, I had set up my workshops upon a desert island in the

ocean. There my workmen, that is to say, the brave men that I

instructed and educated, and myself have put together our Nautilus.

Then, when the work was finished, fire destroyed all trace of our

proceedings on this island, that I could have jumped over if I had

liked."



"Then the cost of this vessel is great?"



"M. Aronnax, an iron vessel costs L145 per ton. Now the Nautilus

weighed 1,500. It came therefore to L67,500, and L80,000 more for

fitting it up, and about L200,000, with the works of art and the

collections it contains."



"One last question, Captain Nemo."



"Ask it, Professor."



"You are rich?"



"Immensely rich, sir; and I could, without missing it, pay the national

debt of France."



I stared at the singular person who spoke thus. Was he playing upon my

credulity? The future would decide that.