I obeyed, and he began thus: –
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