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.’
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