and six of her original coal-fired boilers were replaced by oil-fired du Temple boilers. Jean Barts fire-control systems were comprehensively upgraded with the installation of a Saint-Chamond-Granat system in a director-control tower (DCT) on the top of the tripod mast and all her original rangefinders were replaced with the exception of the Barr & Stroud FT rangefinders in the main-gun turrets. The DCT was fitted with a Barr & Stroud Modèle 1912 coincidence rangefinder and a Zeiss stereoscopic rangefinder was added to the DCT to measure the distance between the target and shell splashes. Additional 4.57-metre Mle 1912 rangefinders were added in a duplex mounting atop the conning tower and another at the base of the mainmast. A traversable Zeiss rangefinder was fitted to the roof of the forward superfiring turret in lieu of its FT model rangefinder and FTs were installed in the new gunnery directors for the secondary armament. The ship's Mle 1918 AA guns were exchanged for seven Canon de 75 mm Modèle 1922 guns and they were provided with a pair of high-angle OPL Modèle 1926 stereoscopic rangefinders, one on top of the duplex unit on the roof of the conning tower and one in the aft superstructure. The modernisation was completed on 29 September 1931 and Jean Bart recommissioned on 1 October as the flagship of the 2nd Battle Division commanded by Rear Admiral () Hervé. Her machinery trials lasted until 13 February 1932 and she then made port visits to Bizerte, Crete, Egypt, French Lebanon, Corfu, and Greece in April and May. Rear Admiral Jean-Pierre Esteva relieved Hervé on 1 August and the ship was refitted from 10 October to 24 November in Toulon after which she spent five days in Ajaccio, Corsica. Jean Bart exercised with the Mediterranean Squadron in the first half of 1933 and made port visits in French North Africa, Majorca, Spain and Casablanca, French Morocco. After a collision on 6 August with the destroyer in Toulon harbour that damaged the latter's stern, the battleship was under repair from 8 to 15 August. From 20 April to 29 June 1934, the Mediterranean Squadron conducted its usual manoeuvres and port visits. The 2nd Battle Division was disbanded on 1 August and Jean Bart briefly served as the squadron flagship. The ship was assigned to the Training Division on 1 November and served as a school for stokers and signalmen. She made