Twenty Thousand Leagues Under the Sea as an inhabitant of British Colonial India, "is an inhabitant of an oppressed country". Verne took the name "Nautilus" from one of the earliest successful submarines, built in 1800 by Robert Fulton, who later invented the first commercially successful steamboat. Fulton's submarine was named after the paper nautilus because it had a sail. Three years before writing his novel, Jules Verne also studied a model of the newly developed French Navy submarine "Plongeur" at the 1867 Exposition Universelle, which inspired him for his definition of the "Nautilus". The breathing apparatus used by "Nautilus" divers is depicted as an untethered version
Jules Verne Denmark to return in haste to Paris, but missed the birth on 3 August 1861 of his only biological son, Michel. Meanwhile, Verne continued work on the idea of a "Roman de la Science", which he developed in a rough draft inspired, according to his recollections, by his "love for maps and the great explorers of the world". It took shape as a story of travel across Africa and would eventually become his first published novel, "Five Weeks in a Balloon". In 1862, through their mutual acquaintance Alfred de Bréhat, Verne came into contact with the publisher Pierre-Jules Hetzel, and