The Nautilus was designed and commanded by Captain Nemo, a former Indian prince and engineer. Its engines were powered by electricity from sodium-mercury batteries, and the crew harvest the seas to get all their staples.
From its attacks on ships, using a ramming prow to puncture target vessels below the waterline, the world thought it a sea monster.
(Warning: Wikipedia contains spoilers):
At the end of "Twenty Thousand Leagues", the ship is sucked into the Maelstrom.
Tell us more about the Nautilus as described by Jules Verne