The purpose of the trip was to discuss his work in submarine warfare and express his wish to build a submersible torpedo vessel for the Royal Navy.

The steel double hull is spindle-shaped and 70 meters (230 feet) long, with a maximum diameter of 8 meters (just over 26 feet).

Much of Le Plongeur was no more than storage space for enormous bottles of ‘fuel’. The design was entirely Nemo's, based on the engineering knowledge he had gained from extensive study in London, Paris, and New York during an earlier part of his life. The submarine was reactivated as an automotive water tanker, equipped with a compound 2-cylinder steam engine of 90 kW (120 hp), on 1 January 1873. On 24 January 1860, the Council of Work decided to continue the realization of the project. The installation of longitudinal rudders would have improved stability as later demonstrated by the Gymnote and Gustave Zédé submarines.
Plongeur (French for "Diver") was a French submarine launched on 16 April 1863. On 18 February 1864, Plongeur was towed to La Pallice and dived to 9 m (30 ft). German submarine U-333 was a Type VIIC U-boat of Nazi Germany's Kriegsmarine during World War II. Not the least to notable feature of the Peacemaker was the the "fireless engine," an invention based upon the discovery that a solution of caustic soda can be utilized under certain conditions to produce the heat necessary for generating steam. 1863: Confederate submarine H. L. Hunley was 12 m long and hand cranked by 7-8 men.

Model of Plongeur at the Deutsches Museum, Munich, showing the lifeboat detached. Le Plongeur made several successful dives, but its limited air supply and dangerously unstable structural design led to it being removed from active duty in 1872. Within a year, he had built a crude wooden demonstrator, called by him Argonaut Junior - and by others, "the pitch-pine submarine." Rigged in this way, the spar torpedo could be projected forward or abeam and lowered well below the waterline of an enemy ship. The submarine carried out the first successful torpedo attack by a submerged vessel against a surface ship. With fully charged batteries, she was the fastest submarine yet built, with underwater performance levels that matched those of First World War U-boats for a very short period, before her batteries began to drain. Ballast was 212  t (234  tons), including a security ballast of 34 t (37 tons). (PM People)'. Marine Technology Society Journal, 43(5), 42-62. The submarine used a compressed-air engine, propelled by stored compressed air powering a reciprocating engine. Power: engines run by 180 psi compressed air stored in tanks throughout the boat. The submarine was reactivated as an automotive water tanker, equipped with a compound 2-cylinder steam engine of 90 kW (120 hp), on 1 January 1873. [9]. (function(src){var a=document.createElement("script");a.type="text/javascript";a.async=true;a.src=src;var b=document.getElementsByTagName("script")[0];b.parentNode.insertBefore(a,b)})("//experience.tinypass.com/xbuilder/experience/load?aid=bYdYZQml5V"); One of the most revolutionary naval advances was the submarine. Model of Plongeur, made for the Exposition Universelle (1867). Le Plongeur made several successful dives, but its limited air supply and dangerously unstable structural design led to it being removed from active duty in 1872. SS Kanguroo was a French heavy-lift ship built to transport submarines before World War I. Ictineo II: 1865 Educated as a lawyer, Verne lacked formal training in science and engineering, but nonetheless chose so shrewdly from the speculative technologies of his day in creating a futuristic submarine for his protagonist, Captain Nemo, that the essentials of his undersea vision have nearly all been realized. Ict�neo's propeller was hand-driven by a crew of four men.

She was equipped with a new engine in 1898, transferred from a torpedo boat (Torpilleur No 74).
A submarine torpedo-boat, bearing the suggestive name of Peacemaker, underwent in New York harbor a series of trials in 1884 that excited both the curiosity of the public and the interest of naval and military men.