# French ironclad Jemmapes

Jemmapes was the lead ship of a class of two coastal defense ships built for the French Navy (Marine Nationale) in the 1890s. Launched in 1892, the vessel joined the Northern Squadron of the French Navy (Esadre du Nord) at Brest. Armed with a main armament of two 274 mm (10.8 in) guns, the vessel was designed within the principles of the Jeune École. The ship joined the Northern Squadron, which was called, "the most homogenous and dangerous squadron that one could meet at sea". Jemmapes took part in a large naval exercise in 1895 but otherwise had an uneventful career as French naval doctrine moved from a fleet of smaller coastal defense ships to larger ocean-going battleships. The ship was decommissioned in 1910 and served as a hulk before being sold in 1927 to be broken up.

## Design and description

A larger and more capable design based on the French ironclad Furieux launched in 1883, Jemmapes was the lead ship of a class of two coastal defense ships designed by de Bussy for the French Navy (Marine Nationale) as part of a wider adoption of the principles of Jeune École. The design was to have a similar level of armament, armour, draught and fuel storage as the preceding design but with a more modern powerplant based on Belleville boilers that would provide an increase in speed to 16 kn (30 km/h; 18 mph). The design proposal was accepted by the Board of Construction (Conseil de travaux) on 26 February 1889, finalised on 2 July and approved by the Minister of the Navy (Ministère de la Marine) Jules François Émile Krantz on 6 July.
Jemmapes had an overall length of 89.6 m (294 ft 0 in), 89.35 m (293 ft 2 in) at the waterline and86.535 m (283 ft 10.9 in) between perpendiculars, a beam of 17.48 m (57 ft 4 in) at the waterline and a mean draught of 6.703 m (21 ft 11.9 in) at deep load. The vessel displaced 6,579 metric tons (6,475 long tons) and had a ship's complement that numbered 299 sailors of all ranks.
Jemmapes was powered by two triple-expansion steam engines that each drove one propeller shaft using steam provided by 16 Lagrafel and d'Allest Belleville boilers. The engine was rated at 8,400 indicated horsepower (6,300 kW) at 108rpm. While undertaking sea trials, Jemmapes reached a speed of 15.68 knots (29.0 km/h; 18.0 mph) from 9,118 ihp (6,799 kW). In service, speed was restricted as a bow wave was created at 13 knots (24 km/h; 15 mph) which, by 15 knots (28 km/h; 17 mph) became impossible to push forward, meaning this became the de facto maximum speed. The ship carried 335 tonnes (330 long tons; 369 short tons) of coal, which gave a range of 2,667 nautical miles (4,939 km; 3,069 mi) at a cruising speed of 10.9 knots (20.2 km/h; 12.5 mph). The maximum load of coal was 350.84 tonnes (345.30 long tons; 386.73 short tons). Once in service, a range of 1,000 nautical miles (1,900 km; 1,200 mi) at 14 knots (25.9 km/h; 16.1 mph) was claimed.
Jemmapes carried a main battery of two Canon de 274 mm (10.8 in) Modèle 1887 guns in a two single-gun turrets, one forward of the superstructure and the other aft. The guns were manually-loaded and fired one round every five minutes, but this was sped up between 1900 and 1902 with new equipment. Secondary armament was provided by four 100 mm (3.9 in) 45-calibre M1891 QF guns mounted at the corners of the shelter deck. Defence from torpedo boats was provided by six Canon de 47 mm (1.9 in) Modèle 1885 Hotchkiss guns and eight 37-millimetre (1.5 in) Hotchkiss revolving cannon.
The ship had a full-length waterline armor belt that tapered from the maximum thickness of 460 mm (18 in) amidships to 410 mm (16 in) aft and 310 mm (12 in) forward. The belt was 1.9 m (75 in) high amidships. The armor was hammered steel on the port side and compound armor on the starboard. The turrets were protected by 450 mm (18 in) thick compound armor that was mounted on fixed bases 400 mm (16 in) thick while the gun shields for the secondary armament was provided by hammered steel armor 80 mm (3.1 in) thick. The main deck was protected by 50-millimeter (2 in) thick iron plates. The laminated steel plates protecting the conning tower measured 80 mm (3.1 in) in thickness.

## Construction and career

Ordered on 18 December 1889 from Ateliers et Chantiers de la Loire of Saint-Nazaire and Saint-Denis, Jemmapes was laid down on 26 December, and launched on 27 April 1892. The vessel cost £525,000. The ship's machinery was fully installed on 3 July 1893 and the vessel was moved to Brest on 24 December. Initially commissioned for trials on 19 January 1884, Jemmapes had to wait until her machinery was accepted on 31 January the following year before being fully commissioned on 4 March. She joined the Northern Squadron (Esadre du Nord) of the French Navy 12 days later. On 12 March, as part of the naval budget debate, Vice Admiral Armand Bernard declared that the squadron, which included three other ships alongside Jemmapes, was "the most homogenous and dangerous squadron that one could meet at sea". They were considered more than equal to their smaller German contemporaries, the Odin class and Siegfried class.
Jemmapes had a generally uneventful career. Between 1 and 23 July 1895, the vessel took part in a large naval exercise in the Atlantic Ocean as part of the Northern Squadron. The manoeuvres included a forced landing at Quiberon and a mock blockade and attack on Cherbourg and Rochefort. The vessel served as part of the defending force, which was successful in resisting the attack. The ship also took part in the maneuvers the following year, conducted from 6 to 26 July in conjunction with the local defense forces of Brest, Rochefort, Cherbourg, and Lorient. The squadron was divided into three divisions for the maneuvers, and Jemmapes was assigned to the 2nd Division along with her sister ship Valmy, the cruiser Chasseloup-Laubat and the aviso Salve, which represented part of the defending French squadron. At the end of the century, the vessel was part of the Coastal Defence Division alongside the ironclads Amiral Tréhouart, Bouvines and Valmy.
Meanwhile, French naval doctrine was changing and the focus on coastal defense was being replaced by one of larger sea-going warships. The size of ships was also increasing, and newer, more capable battleships entered service. Jemmapes was transferred to reserve at Cherbourg between 1902 and 20 September 1909, returning to service at Brest for just over two months before being briefly transferred to Rochefort on 9 December. The vessel was decommissioned at Rochefort on 22 March 1910 and struck on 3 August. Jemmapes served as a hulk for more than a decade until she was sold to Société Goldenberg on 5 November 1927 to be broken up.

## Citations

* 1 2 3 4 5 Roberts 2021, p. 208.
* ↑ Paloczi-Horvath 1996, p. 49.
* ↑ Roche 1898, p. 162.
* 1 2 3 Roberts 2021, p. 209.
* ↑ Brassey 1897, p. 264.
* ↑ Roberts 2021, p. 204.
* ↑ Paloczi-Horvath 1996, p. 48.
* ↑ Barry 1896, pp. 187, 190.
* ↑ Barry 1896, pp. 186, 189.
* ↑ Thursfield 1897, p. 167.
* ↑ Brassey 1899, p. 70.
* ↑ Paloczi-Horvath 1996, p. 50.