Jules Verne, Une Ville flottante, Les Forceurs de Blocus, Collection Hetzel.

"More than a ship, it is a floating city. If the Great Eastern is not only a nautical machine, if it is a microcosm, an observer will not be surprised to find there all the instincts, all the ridiculousness, all the passions of men. "Rumours are rife as one crosses the bridge of the Great Eastern: from the cabins to the holds, there is talk of disturbing disappearances... One of the captains is said to have drowned, a passenger is said to have wandered off into the depths of the ship, and a mechanic is said to have been welded in the steam box! Hypnotised by the ship's disproportionate size, the narrator embarks on a journey that holds many surprises.
After the short novel A Floating City, another short story by Jules Verne, Les forceurs de blocus, also published in 1871 after A Floating City.
This time Jules Verne transports us to the middle of the American Civil War, in 1862, with a view of the other side of the Atlantic. James Playfair, a captain but above all a trader, cannot stand still in the face of the crisis that is brewing in Glasgow: the war between the Northern and Southern states is causing a shortage of cotton, which is very bad for business. He decides to implement a plan that will allow the family business to get out of the water: build an extremely fast steamer, the Delphin, enough to outrun the Federal ships and corvettes in order to break the blockade of Charleston and send a cargo of arms that he will exchange for cotton at a good price by doing business with the Confederates