The Jean Bart class comprised two protected cruisers of the French Navy built in the late 1880s and early 1890s; the two ships were and . They were ordered as part of a fleet program that accorded with the theories of the , which proposed a fleet based on cruisers and torpedo boats to defend France. The Jean Bart-class cruisers were intended to serve a long-range commerce raiders to attack enemy merchant shipping. The ships were armed with a main battery of four guns supported by six guns and they had a top speed of .
After entering service, Isly was assigned to the Northern Squadron, while Jean Bart operated with the Mediterranean Squadron until 1895, when she, too, joined the Northern Squadron. That year, Isly was sent to French Indochina, and they were followed by Jean Bart followed in 1898. Jean Bart was present in the Far East during the Boxer Uprising in Qing China the following year, by which time Isly had been transferred to the North Atlantic station. Jean Bart was wrecked off the coast of the Western Sahara in 1907 and could not be refloated. Isly was converted into a depot ship in 1909 before being sold to ship breakers in 1914.
Design
The French naval minister, Charles-Eugène Galiber, drew up specifications for a new commerce raiding cruiser in mid-1885, which he submitted to the (Council of Works) for consideration on 12 June. The new ship was to generally follow the patter of the earlier cruiser , but slightly smaller and a revised armament. Unlike Amiral Cécille, which carried a large secondary battery, the new ship would carry only a few medium guns. The examined Galiber's proposal in a meeting on 15 July, and they approved it largely without changes, apart from increasing the displacement from to . Galiber took the revised specifications and forwarded them to France's shipyards on 21 July to request refined design proposals.
Eight shipyards responded by early 1886, which the examined in a meeting on 2 March. They accepted four of the proposals for further refinement, and on 31 July, two of these were formally accepted. The first, drawn up by Jules Thibaudier, became Jean Bart; the second became the similar cruiser . Because they were approved at the same time and were generally similar, the two ships are sometimes considered to be the same class, and are referred to as the Alger class, but they are in fact different designs that vary considerably in their particulars.
By this time, Admiral Théophile Aube had replaced Galiber as naval minister. Aube was an ardent supporter of the doctrine, which envisioned using a combination of cruisers and torpedo boats to defend France and attack enemy merchant shipping. By the time Aube had come to office, the French Navy had laid down three large protected cruisers that were intended to serve as commerce raiders: , , and Amiral Cécille. His proposed budget called for another six large cruisers and ten smaller vessels, but by the time it was approved later in 1886, it had been modified to three large cruisers, two medium cruisers, and six small cruisers.
To meet the requirement for the large vessels, Aube ordered a second member of the Jean Bart class, which was named Dupuy de Lôme. In November, the second ship was cancelled in favor of a second member of the Alger class, but on 1 March 1887, the navy ordered another Jean Bart-class cruiser named . The ships were originally intended to carry a three-masted barque sailing rig, but on 4 May 1888, Jules François Émile Krantz, who was by then the naval minister, ordered the rig to be removed in favor of heavy military masts. The light armament was also revised, as the masts were intended to carry some of these guns. The Jean Bart class and Alger proved to be the last of the large commerce-raiding cruisers built for the French fleet ordered by Aube. The French Navy would later return to the idea with and in the late 1890s.
General characteristics and machinery
The ships of the Jean Bart class were long at the waterline and long overall, with a beam of and am average draft of , which increased to aft. They displaced normally, and at full load, Jean Bart and Isly displaced , respectively. Their hulls featured a pronounced ram bow and a tumblehome shape, along with a sloped, overhanging stern. The bow was not strengthened to allow the ships to ram an opponent, however. The ships had a minimal superstructure, consisting primarily of a small conning tower and bridge forward. The cruisers carried a pair of heavy military masts fitted with fighting tops for some of their light guns and observation positions. Their crew varied over the course of their careers, amounting to 331–405 officers and enlisted men.