Floating battery

A floating battery is a kind of armed watercraft, often improvised or experimental, which carries a heavy armament but has few other qualities as a warship.

An early appearance was in 1782 at the Great Siege of Gibraltar, and its invention and usage is attributed to Spanish lieutenant general Antonio Barceló.

A purpose-built floating battery was Flådebatteri No. 1, designed by Chief Engineer Henrik Gerner in 1787; it was 47 m long, 13 m wide and armed with 24 guns, and was used during the 1801 battle of Copenhagen under command of Peter Willemoes. The British made limited use of floating batteries during the French Revolutionary and Napoleonic Wars, with the two-vessel Musquito and Firm-class floating batteries, and some individual vessels.

The most notable floating batteries were built or designed in the 19th century, and are related to the development of the first steam warship and the ironclad warship.

Demologos, the first steam-propelled warship, was a floating battery designed for the protection of New York Harbor in the War of 1812.

In the 1850s, the British and French navies deployed iron-armoured floating batteries as a supplement to the wooden steam battlefleet in the Crimean War. The role of the battery was to assist unarmoured mortar and gunboats bombarding shore fortifications. The French used their batteries in 1855 against the defenses at Kinburn on the Black Sea, where they were effective against Russian shore defences. The British planned to use theirs in the Baltic Sea against Kronstadt, and may have been influential in causing the Russians to sue for peace. However, Kronstadt was widely regarded as the most heavily fortified naval arsenal in the world throughout most of the 19th-century, continually upgrading its combined defences to meet new changes in technology. Even as the British armoured-batteries were readied against Kronstadt in early 1856, the Russians had already constructed newer networks of outlying forts, mortar batteries of their own, and submarine mines against which the British had no system for removing under fire.

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