These guns fired shells at muzzle velocities of . Twelve 40-caliber Canon de 47 mm Modèle 1885 Hotchkiss guns were mounted as anti-torpedo boat guns. They were mounted in platforms in the foremast and mainmast and on the superstructure. They fired a projectile at to a maximum range of . Their theoretical maximum rate of fire was fifteen rounds per minute, but only seven rounds per minute sustained. Two submerged torpedo tubes were also carried. Exactly which types of torpedoes carried is unknown, but most of the torpedoes in service during the war had warheads of , maximum speeds of and maximum ranges of . "Henri IV" had a waterline armor belt of Harvey armor that was high and tapered from the maximum thickness of that to at the ship's ends. The belt ended short of the stern in a traverse bulkhead. The lower edge of this belt tapered as well from in thickness. The upper armor belt was mostly thick and ran from the bow to aft of the midsection. It was generally high, but increased to forward and ended in a traverse bulkhead. The maximum thickness of the armored deck was , but tapered to at the ship's ends. Below this was a thinner armored deck that tapered from on the centerline to at the edges. It curved down about to form a torpedo bulkhead before it met up with the inner bottom. This system was based on experiments conducted in 1894 and was more modern than that used in the Russian battleship "Tsesarevich" although it was still too close to the side of the ship. The main turret armor was in thickness and the ammunition shafts were protected by of armor. The casemates for the 138 mm guns ranged from in thickness and their ammunition tubes had of armor. "Henri IV" was laid down at Cherbourg on 15 July 1897 and launched on 23 August 1899, but did not enter service until September 1903, at a cost of ₣15,660,000 francs. The ship spent the early part of World War I as the guardship at Bizerte, until February 1915 when she was assigned to the newly formed Syrian Squadron ("escadre de Syrie"). This squadron was intended to attack Turkish positions and lines of communication in Syria, Lebanon, Palestine and the Sinai Peninsula. "Henri IV" was transferred to the French squadron in the Dardanelles campaign to replace the sunk battleship and the damaged after the Allies suffered heavily during their first attempt to sail through the Dardanelles and past the fortifications them on 18 March 1915.