Nautilus (Verne) from seawater) is the craft's primary power source for propulsion and other services. "Nautilus" is double-hulled, and is further separated into water-tight compartments. Its top speed is . Its displacement is submerged. In Captain Nemo's own words: "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 "Nautilus" to believe that the vessel is some species of whale, or perhaps a
Jules Verne "Voyages extraordinaires" series continued for several years afterwards at the same rate of two volumes a year. It was later discovered that Michel Verne had made extensive changes in these stories, and the original versions were eventually published at the end of the 20th century by the Jules Verne Society (Société Jules Verne). In 1919, Michel Verne published The Barsac Mission (), which original drafts contained references to Esperanto, language about which his father had great interest. In 1989, Verne's great-grandson discovered his ancestor's as yet unpublished novel "Paris in the Twentieth Century" which was subsequently published in 1994. Verne's