The Nautilus is a legendary submarine created and captained by Captain Nemo. The Nautilus is described by many as "a masterpiece containing masterpieces". It is designed and commanded by Captain Nemo. Electricity provided by sodium/mercury batteries (with the sodium provided by extraction from seawater) is the craft's primary power source for propulsion and other services.
Its parts are built to order in France, the United Kingdom, Prussia, Sweden, the United States, and elsewhere. Then they are assembled by Nemo's men on a desert island. The Nautilus most likely returned to this island and later helped castaways. After Nemo dies on board, the volcanic island erupts, entombing the Captain and the Nautilus for eternity.
The Nautilus is double-hulled, and is further separated into water-tight compartments. Its top speed is 50 knots. Its displacement is 1,356.48 French freight tons emerged (1,507 submerged). According to Captain Nemo, "it is an elongated cylinder with conical ends, very like a cigar in shape, a shape already adopted in London in several constructions of the same sort. The length of this cylinder, from stem to stern, is exactly 70 m, and its maximum breadth is eight metres. It is not built on a ratio of ten to one 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 one to obtain by a simple calculation the surface and cubic contents of the Nautilus. Its area measures 1011.45 square metres; and its contents 1,500.2 cubic meters; that is to say, when completely immersed it displaces 1500.2 cubic meters of water, or 1500.2 metric tons."
The Nautilus uses floodable tanks in order to adjust buoyancy and so control its depth. The pumps that evacuate these tanks of water are so powerful that they produce large jets of water when the vessel emerges rapidly from the surface of the water. This leads many early observers of the Nautilus to believe that the vessel is some species of whale, or perhaps a sea monster not yet known to science. To submerge deeply in a short time, Nautilus uses a technique called "hydroplaning", in which the vessel dives down at a steep angle.
Much of the ship is decorated to standards of luxury that are unequalled in a seagoing vessel of the time. These include a library with boxed collections of valuable oceanic specimens that are unknown to science at the time, expensive paintings, and several collections of jewels. The Nautilus also features a lavish dining room and even an organ that Captain Nemo uses to entertain himself in the evening. By comparison, Nemo's personal quarters are very sparsely furnished, but do feature duplicates of the bridge instruments, so that the captain can keep track of the vessel without being present on the bridge. These amenities, however, are only available to Nemo and his companions.
The Nautilus supports a crew that gathers and farms food from the sea. The Nautilus includes a galley for preparing these foods, which includes a machine that makes drinking water from seawater through distillation. The Nautilus is not able to refresh its air supply, so Captain Nemo designed to do it by surfacing and exchanging stale air for fresh, much like a whale. The Nautilus is capable of extended voyages without refueling or otherwise restocking supplies. Its maximum dive time is around five days.