20,000 Leagues Under The Sea

CHAPTER 12 Everything by Electricity

‘Sir,’ said Captain Nemo, showing me the instruments hung on the walls of the room, ‘here are the instruments necessary for the navigation of the Nautilus. Here, as in the saloon, I have them always before me, and they indicate my position and exact direction in the midst of the ocean. You are acquainted with some of them.’

‘Yes,’ I answered; ‘I understand the usual nautical instruments. But I see others that doubtless answer the peculiar requirements of your vessel. That dial with a movable needle is a manometer, is it not?’

‘Yes, by communication with the water it indicates the exterior pressure and gives our depth at the same time.’

‘And these sounding-lines of a novel kind?’

‘They are thermometric, and give the temperature of the different depths of water.’

‘And these other instruments, the use of which I cannot guess?’

‘Here I ought to give you some explanation, professor. There is a powerful, obedient, rapid, and easy agent which lends itself to all uses, and reigns supreme here. We do everything by its means. It is the light, warmth, and soul of my mechanical apparatus. This agent is electricity.’

‘Yes, captain, you possess an extreme rapidity of movement which does not well agree with the power of electricity. Until now its dynamic force has been very restricted, and has only produced little power.’

‘Professor,’ answered Captain Nemo, ‘my electricity is not everybody’s, and you will permit me to withhold any further information.’

‘I will not insist, sir; I will content myself with being astonished at such wonderful results. A single question, however, I will ask, which you need not answer if it is an indiscreet one. The elements which you employ to produce this marvellous agent must necessarily be soon consumed. The zinc, for instance, that you use – how do you obtain a fresh supply? You now have no communication with the land?’

‘I will answer your question,’ replied Captain Nemo.

‘In the first place I must inform you that there exist, at the bottom of the sea, mines of zinc, iron, silver, and gold, the working of which would most certainly be practicable; but I am not indebted to any of these terrestrial metals. I was determined to seek from the sea alone the means of producing my electricity.’

‘From the sea?’

‘Yes, professor, and I was at no loss to find these means. It would have been possible, by establishing a circuit between wires plunged to different depths, to obtain electricity by the diversity of temperature to which they would have been exposed; but I preferred to employ a more practicable system.’

‘And what was that?’

‘You know the composition of sea-water? Chloride of sodium forms a notable proportion of it. Now it is this sodium that I extract from sea-water, and of which I compose my ingredients. Mixed with mercury it takes the place of zinc for the voltaic pile. The mercury is never exhausted; only the sodium is consumed, and the sea itself gives me that. Besides, the electric power of the sodium piles is double that of zinc ones.’

‘I clearly understand, captain, the convenience of sodium in the circumstances in which you are placed. The sea contains it. Good. But you still have to make it, to extract it, in a word. And how do you do that? Your pile would evidently serve the purpose of extracting it; but the consumption of sodium necessitated by the electrical apparatus would exceed the quantity extracted. You would consume more than you would produce.’

‘I do not extract it by the pile, professor. I employ nothing but the heat of coal.’

‘Coal!’ I urged.

‘We will call it sea-coal if you like,’ replied Captain Nemo.

‘And are you able to work submarine coal-mines?’

‘You shall see me so employed, M. Aronnax. I only ask you for a little patience; you have time to be patient here. I get everything from the ocean. It produces electricity, and electricity supplies the Nautilus with light – in a word, with life.’

‘But not with the air you breathe.’

‘I could produce the air necessary for my consumption, but I do not, because I go up to the surface of the water when I please. But though electricity does not furnish me with the air to breathe, it works the powerful pumps which store it up in special reservoirs, and which enable me to prolong at need, and as long as I like, my stay in the depths of the sea.’

‘Captain,’ I replied, ‘I can do nothing but admire. You have evidently discovered what mankind at large will, no doubt, one day discover, the veritable dynamic power of electricity.’

‘Whether they will discover it I do not know,’ replied Captain Nemo coldly. ‘However that may be, you now know the first application that I have made of this precious agent. It is electricity that furnishes us with a light that surpasses in uniformity and continuity that of the sun itself. Look now at this clock! It is an electric one, and goes with a regularity that defies the best of chronometers. I have divided it into twenty-four hours, like the Italian clocks, because there exists for me neither night nor day, sun nor moon, only this factitious light that I take with me to the bottom of the sea. Look! just now it is 10 a.m.’

‘Exactly so.’

‘This dial hanging in front of us indicates the speed of the Nautilus. An electric wire puts it into communication with the screw. Look! just now we are going along at the moderate speed of fifteen miles an hour. But we have not finished yet, M. Aronnax,’ continued Captain Nemo, rising, ‘if you will follow me we will visit the stern of the Nautilus.’

I followed Captain Nemo across the waist, and in the centre of the boat came to a sort of well that opened between two water-tight partitions. An iron ladder, fastened by an iron hook to the partition, led to the upper end. I asked the captain what it was for.

‘It leads to the boat,’ answered he.

‘What! have you a boat?’ I exclaimed in astonishment.

‘Certainly, an excellent one, light and unsinkable, that serves either for fishing or pleasure trips.’

‘Then when you wish to embark you are obliged to go up to the surface of the water.’

‘Not at all. The boat is fixed on the top of the Nautilus in a cavity made for it. It has a deck, is quite water-tight, and fastened by solid bolts. This ladder leads to a man-hole in the hull of the Nautilus, corresponding to a similar hole in the boat. It is by this double opening that I get to the boat. The one is shut by my men in the vessel, I shut the one in the boat by means of screw pressure, I undo the bolts, and the little boat darts up to the surface of the sea with prodigious rapidity. I then open the panel of the deck, carefully closed before, I mast it, hoist my sail, take my oars, and am off.’

‘But how do you return?’

‘I do not return to it; it comes to me.’

‘At your order?’

‘At my order. An electric wire connects us. I telegraph my orders.’

‘Really,’ I said, intoxicated by such marvels, ‘nothing can be more simple!’

After having passed the companion ladder that led to the platform, I saw a cabin about twelve feet long, in which Conseil and Ned Land were devouring their meal. Then a door opened upon a kitchen nine feet long, situated between the vast store-rooms of the vessel. There electricity, better than gas itself, did all the cooking. The wires under the stoves communicated with platinum sponges, and gave out a heat which was regularly kept up and distributed. They also heated a distilling apparatus which, by evaporation, furnished excellent drinking water. A bathroom, comfortably furnished with hot and cold water taps, opened out of this kitchen.

Next to the kitchen was the berth-room of the vessel, eighteen feet long. But the door was closed, and I could not see how it was furnished, which might have given me an idea of the number of men employed on board the Nautilus. At the far end was a fourth partition, which separated this room from the engine-room. A door opened, and I entered the compartment where Captain Nemo – certainly a first-rate engineer – had arranged his locomotive machinery. It was well lighted, and did not measure less than sixty-five feet. It was naturally divided into two parts; the first contained the materials for producing electricity, and the second the machinery that moved the screw. I was at first surprised at a smell sui generis which filled the compartment. The captain saw that I perceived it.

‘It is only a slight escape of gas produced by the use of the sodium, and not much inconvenience, as every morning we purify the vessel by ventilating it in the open air.’

In the meantime I was examining the machinery with great interest.

‘You see,’ said the captain, ‘I use Bunsen’s elements, not Ruhmkorff’s – they would not have been powerful enough. Bunsen’s are fewer in number, but strong and large, which experience proves to be the best. The electricity produced passes to the back, where it works by electro-magnets of great size on a peculiar system of levers and cog-wheels that transmit the movement to the axle of the screw. This one, with a diameter of nineteen feet and a thread twenty-three feet, performs about a hundred and twenty revolutions in a second.’

‘What speed do you obtain from it?’

‘About fifty miles an hour.’

Here was a mystery, but I did not press for a solution of it. How could electricity act with so much power? Where did this almost unlimited force originate? Was it in the excessive tension obtained by some new kind of spools? Was it by its transmission that a system of unknown lever could infinitely increase? (And by a remarkable coincidence, a discovery of this kind is talked of in which a new arrangement of levers produces considerable force. Can the inventor have met with Captain Nemo?).

‘Captain Nemo,’ I replied, ‘I recognise the results, and do not seek to explain them. I saw the Nautilus worked in the presence of the Abraham Lincoln, and I know what to think of its speed. But it is not enough to be able to walk; you must see where you are going; you must be able to direct yourself to the right or left, above or below. How do you reach the great depths, where you find an increasing resistance, which is rated by hundreds of atmospheres? How do you return to the surface of the ocean, or maintain yourself at the proper depth? Am I indiscreet in asking you this question?’

‘Not at all, professor,’ answered the captain, after a slight hesitation. ‘As you are never to leave this submarine boat, come into the saloon – it is our true study – and there you shall learn all you want to know about the Nautilus.’

CHAPTER 13 Figures

A moment afterwards we were seated on a divan in the saloon, with our cigars. The captain spread out a diagram that gave the plan of the Nautilus. Then he began his description in these terms: –

‘Here, M. Aronnax, are the different dimensions of the vessel you are in. It is a very elongated cylinder, with conical ends much like a cigar in shape. The length of this cylinder is exactly 232 feet, and its maximum breadth is 26 feet. Its lines are sufficiently long, and its slope lengthened out to allow the displaced water to escape easily, and opposes no obstacle to its speed. Its surface is 1011 metres and 45 centimetres; its volume, 1500 cubic metres and two-tenths, which is the same as saying that it is entirely immersed. It displaces 50,000 feet of water, and weighs 1500 tons.

‘When I made the plans for this vessel – destined for submarine navigation – I wished that when it was in equilibrium nine-tenths of it should be under water, and one-tenth only should emerge. Consequently, under these conditions, it only ought to displace nine-tenths of its volume, or 1356 cubic metres and 48 centimetres – that is to say, it only ought to weigh the same number of tons. I therefore did not exceed this weight in constructing it according to the above-named dimensions.

‘The Nautilus is composed of two hulls, one inside the other, and joined by T-shaped irons, which make it very strong. Owing to this cellular arrangement it resists as if it were solid. Its sides cannot yield; they adhere spontaneously, and not by the closeness of their rivets; and the homogeneity of their construction, due to the perfect union of the materials, enables my vessel to defy the roughest seas.

‘Then when the Nautilus is afloat, one-tenth is out of the water. I have placed reservoirs of a size equal to this tenth capable of holding 150.72 tons, and when I fill them with water the vessel becomes completely immersed. These reservoirs exist in the lowest parts of the Nautilus. I turn on taps, they fill, and the vessel sinks just below the surface of the water.’

‘Well, captain, I can understand your being able to keep just level with the surface of the ocean. But lower down, when you plunge below that surface, does not your submarine apparatus meet with a pressure from below, which must be equal to one atmosphere for every thirty feet of water?’

‘True, sir.’

‘Then unless you fill the Nautilus entirely, I do not see how you can draw it down into the bosom of the liquid mass.’

‘Professor,’ answered Captain Nemo, ‘you must not confound statics with dynamics, or you will expose yourself to grave errors. There is very little work necessary to reach the lowest depths of the ocean, for bodies have a tendency “to sink.” Follow my reasoning.’

‘I am listening to you, captain.’

‘When I wished to determine the increase of weight that must be given to the Nautilus to sink it, I had only to occupy myself with the reduction in volume which sea-water experiences as it becomes deeper and deeper.

‘Now if water is not absolutely incompressible, it is, at least, very slightly compressible – in fact, according to the most recent calculations .0000436 in an atmosphere or in each thirty feet of depth. If I wish to go to the depth of 1000 metres, I take into account the reduction of volume under a pressure of 100 atmospheres. I ought, therefore, to increase the weight so as to weigh 1513.79 tons instead of 1507.2 tons. The augmentation will only be 6.77 tons. Now I have supplementary reservoirs capable of embarking 100 tons. When I wish to remount to the surface, I have only to let out this water, and empty all the reservoirs, if I desire that the Nautilus should emerge one tenth of its total capacity.’

To this reasoning, founded upon figures, I had nothing to object.

‘I admit your calculations, captain,’ I replied, ‘and I should be foolish to dispute them, as experience proves them every day, but I foresee a real difficulty.’

‘What is that, sir?’

‘When you are at the depth of 1000 yards the sides of the Nautilus support a pressure of 100 atmospheres. If, therefore, at this moment, you wish to empty the supplementary reservoirs to lighten your vessel and ascend to the surface, the pumps must conquer this pressure of 100 atmospheres, which is that of 100 kilogrammes for every square centimetre. Hence a power –’

‘Which electricity alone can give me,’ hastened to say Captain Nemo. ‘The dynamic power of my machines is nearly infinite. The pumps of the Nautilus have prodigious force, which you must have seen when their columns of water were precipitated like a torrent over the Abraham Lincoln. Besides, I only use supplementary reservoirs to obtain middle depths of 1500 to 2000 metres, and that in order to save my apparatus. When the fancy takes me to visit the depths of the ocean at two or three leagues below its surface, I use longer means, but no less infallible.’

‘What are they, captain?’ I asked.

‘That involves my telling you how the Nautilus is worked.’

‘I am all impatience to hear it.’

‘In order to steer my vessel horizontally I use an ordinary rudder, worked by a wheel and tackle. But I can also move the Nautilus by a vertical movement, by means of two inclined planes fastened to the sides and at the centre of flotation, planes that can move in every direction, and are worked from the interior by means of powerful levers. When these planes are kept parallel with the boat it moves horizontally; when slanted, the Nautilus, according to their inclination, and under the influence of the screw, either sinks according to an elongated diagonal, or rises diagonally as it suits me. And even when I wish to rise more quickly to the surface I engage the screw, and the pressure of the water causes the Nautilus to rise vertically like a balloon into the air.’

‘Bravo! captain,’ I cried. ‘But how can the helmsman follow the route you give him in the midst of the waters?’

‘The helmsman is placed in a glass cage jutting from the top of the Nautilus and furnished with lenses.’

‘Capable of resisting such pressure?’

‘Perfectly. Glass, which a blow can break, offers, nevertheless, considerable resistance. During some fishing experiments we made in 1864, by electric light, 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.’

‘I see now. But, after all, it is dark under water; how do you see where you are going?’

‘There is a powerful electric reflector placed behind the helmsman’s cage, the rays from which light up the sea for half a mile in front.’

‘Ah, now I can account for the phosphorescence in the supposed narwhal that puzzled me so. May I now ask you if the damage you did to the Scotia was due to an accident?’

‘Yes, it was quite accidental. I was sailing only one fathom below the surface when the shock came. Had it any bad result?’

‘None, sir. But how about the shock you gave the Abraham Lincoln?’

‘Professor, it was a great pity for one of the best ships in the American navy; but they attacked me and I had to defend myself! Besides, I contented myself with putting it out of the power of the frigate to harm me; there will be no difficulty in getting her repaired at the nearest port.’

‘Ah, commander!’ I cried, with conviction, ‘your Nautilus is certainly a marvellous boat.’

‘Yes, professor,’ answered Captain Nemo, with real emotion, ‘and I love it as if it were flesh of my flesh! Though all is danger on one of your ships in subjection to the hazards of the ocean, though on this sea the first impression is the sentiment of unfathomable depth, below and on board the Nautilus the heart of man has nothing to dread. There is no deformation to fear, for the double hull of this vessel is as rigid as iron; no rigging to be injured by rolling and pitching; no sails for the wind to carry away; no boilers for steam to blow up; no fire to dread, as the apparatus is made of iron and not of wood; no coal to get exhausted, as electricity is its mechanical agent; no collision to fear, as it is the only vessel in deep waters; no tempests to set at defiance, as there is perfect tranquillity at some yards below the surface of the sea! The Nautilus is the ship of ships, sir. And if it is true that the engineer has more confidence in the vessel than the constructor, and the constructor more than the captain himself, you will understand with what confidence I trust to my Nautilus, as I am at the same time captain, constructor, and engineer.’

Captain Nemo spoke with captivating eloquence. His fiery look and passionate gestures transfigured him. Yes! he did love his vessel like a father loves his child.

‘But how could you construct this admirable Nautilus in secret?’

‘I had each separate portion made in different parts of the globe, and it reached me through a disguised address. The keel was forged at Creuzot, the shaft of the screw at Penn and Co.’s, of London; the iron plates of the hull at Laird’s, of Liverpool; the screw itself at Scott’s, of Glasgow. Its reservoirs were made by Cail and Co., of Paris; the engine by the Prussian Krupp; the prow in Motala’s workshop in Sweden; the mathematical instruments by Hart Brothers, of New York, etc.; all of these people had my orders under different names.’