French ironclad Gloire

Gloire was France's response to what the Crimean War had revealed: Paixhans guns and rifled artillery firing explosive shells had made unarmoured wooden warships terribly vulnerable, and Anglo-French ironclad floating batteries had already bombarded Russian forts. The naval architect Henri Dupuy de Lôme designed her as a 5,630-ton broadside ironclad, ordered on 4 March 1858 and laid down the same month at the arsenal of Mourillon, Toulon.

Dupuy de Lôme had wanted her class fully iron-hulled — he had cancelled all French wooden-hulled construction with that in mind — but iron shortages forced a compromise: Gloire and her first two sisters carried wooden hulls plated with wrought iron. The armour was formidable for its day: 12 cm plates backed by 43 cm of timber, which in experimental firing resisted the strongest guns of the time — the French 50-pounder and the British 68-pounder — at full charge from just 20 metres.

Launched on 24 November 1859 and completed in August 1860, Gloire carried both a steam-driven screw and sail — first a light barquentine rig, later a full rig of 2,508 square metres. French planning imagined her speed chasing the British Channel Fleet out of the English Channel; official trials in August 1860 recorded 13.5 knots, though other reports put her practical maximum nearer 11 knots. In September 1860 she escorted the imperial yacht Aigle carrying Napoleon III to Algiers, and in a storm on the return voyage she was the only escort able to stay with the yacht.

Reports of her construction reached Britain in May 1858 and set off a public outcry, fanned by the newspapers, that forced the Surveyor of the Navy into a public admission: "France has now commenced to build frigates of great speed with their sides protected by thick metal plates, and this renders it imperative for this country to do the same without a moment's delay." The direct result was the armoured frigate HMS Warrior — Britain's reply in iron, conceived because a single French ship at Toulon had made the Royal Navy's wooden wall look suddenly antique.

As the first ocean-going ironclad, Gloire rendered the traditional unarmoured wooden ship-of-the-line obsolete at a stroke, and all the major navies soon began building ironclads of their own. The wooden-hulled compromise Dupuy de Lôme had been forced into was itself a measure of how fast the change came: he had already cancelled every French wooden-hull project in anticipation of an all-iron fleet, and only the shortage of iron kept Gloire from being what he intended her to be.

Her own service was brief by the standards of the wooden ships she displaced. She began comparative trials against the Algésiras on 12 November 1860, a programme that ran to its trial report on 30 March 1861, and she was struck off the French naval register in 1879 and scrapped in 1883 — barely twenty years after the launch that set every naval power in Europe building armoured ships.