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Ironclad warship

Ironclad warship

Overview
An ironclad was a steam-propelled
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...

 warship
Warship
A warship is a ship that is built and primarily intended for combat. Warships are usually built in a completely different way from merchant ships. As well as being armed, warships are designed to withstand damage and are usually faster and more maneuvrable than merchant ships...

 in the early part of the second half of the 19th century, protected by iron
Wrought iron
thumb|The [[Eiffel tower]] is constructed from [[puddle iron]], a form of wrought ironWrought iron is an iron alloy with a very low carbon...

 or steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 armor plates. The ironclad was developed as a result of the vulnerability of wooden warships to explosive or incendiary shells
Shell (projectile)
A shell is a payload-carrying projectile, which, as opposed to shot, contains an explosive or other filling, though modern usage sometimes includes large solid projectiles properly termed shot . Solid shot may contain a pyrotechnic compound if a tracer or spotting charge is used...

. The first ironclad battleship, La Gloire
French battleship La Gloire
The French Navy's La Gloire was the first ocean-going ironclad battleship in history.She was developed following the Crimean War, in response to new developments in naval gun technology, especially the Paixhans guns and rifled guns, which used explosive shells with increased destructive power...

, was launched by the French Navy
French Navy
The French Navy, officially the Marine nationale and often called La Royale is the maritime arm of the French military. It includes a full range of fighting vessels, from patrol boats to a nuclear powered aircraft carrier and 10 nuclear-powered submarines, four of which are capable of launching...

 in November 1859. The British Admiralty
Admiralty
The Admiralty was formerly the authority in the Kingdom of England, and later in the United Kingdom, responsible for the command of the Royal Navy...

 had been considering armored warships since 1856 and prepared a draft design for an armored corvette in 1857; however, in early 1859 the Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 started building two iron-hulled armored frigates, and by 1861 had made the decision to move to an all-armored battle fleet.
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Encyclopedia
An ironclad was a steam-propelled
Steam engine
A steam engine is a heat engine that performs mechanical work using steam as its working fluid.Steam engines are external combustion engines, where the working fluid is separate from the combustion products. Non-combustion heat sources such as solar power, nuclear power or geothermal energy may be...

 warship
Warship
A warship is a ship that is built and primarily intended for combat. Warships are usually built in a completely different way from merchant ships. As well as being armed, warships are designed to withstand damage and are usually faster and more maneuvrable than merchant ships...

 in the early part of the second half of the 19th century, protected by iron
Wrought iron
thumb|The [[Eiffel tower]] is constructed from [[puddle iron]], a form of wrought ironWrought iron is an iron alloy with a very low carbon...

 or steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 armor plates. The ironclad was developed as a result of the vulnerability of wooden warships to explosive or incendiary shells
Shell (projectile)
A shell is a payload-carrying projectile, which, as opposed to shot, contains an explosive or other filling, though modern usage sometimes includes large solid projectiles properly termed shot . Solid shot may contain a pyrotechnic compound if a tracer or spotting charge is used...

. The first ironclad battleship, La Gloire
French battleship La Gloire
The French Navy's La Gloire was the first ocean-going ironclad battleship in history.She was developed following the Crimean War, in response to new developments in naval gun technology, especially the Paixhans guns and rifled guns, which used explosive shells with increased destructive power...

, was launched by the French Navy
French Navy
The French Navy, officially the Marine nationale and often called La Royale is the maritime arm of the French military. It includes a full range of fighting vessels, from patrol boats to a nuclear powered aircraft carrier and 10 nuclear-powered submarines, four of which are capable of launching...

 in November 1859. The British Admiralty
Admiralty
The Admiralty was formerly the authority in the Kingdom of England, and later in the United Kingdom, responsible for the command of the Royal Navy...

 had been considering armored warships since 1856 and prepared a draft design for an armored corvette in 1857; however, in early 1859 the Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 started building two iron-hulled armored frigates, and by 1861 had made the decision to move to an all-armored battle fleet. After the first clashes of ironclads
Battle of Hampton Roads
The Battle of Hampton Roads, often referred to as either the Battle of the Monitor and Merrimack or the Battle of Ironclads, was the most noted and arguably most important naval battle of the American Civil War from the standpoint of the development of navies...

 (both with wooden ships and with one another) took place during the American Civil War
American Civil War
The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

, it became clear that the ironclad had replaced the unarmored ship of the line
Ship of the line
A ship of the line was a type of naval warship constructed from the 17th through the mid-19th century to take part in the naval tactic known as the line of battle, in which two columns of opposing warships would manoeuvre to bring the greatest weight of broadside guns to bear...

 as the most powerful warship afloat. This type of ship would come to be very successful in the American Civil War.

Ironclads were designed for several roles, including as high seas battleship
Battleship
A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...

s, coastal defense ships, and long-range cruiser
Cruiser
A cruiser is a type of warship. The term has been in use for several hundreds of years, and has had different meanings throughout this period...

s. The rapid evolution of warship design in the late 19th century transformed the ironclad from a wooden-hulled vessel that carried sails to supplement its steam engines into the steel-built, turreted battleships and cruisers familiar in the 20th century. This change was pushed forward by the development of heavier naval guns (the ironclads of the 1880s carried some of the heaviest guns ever mounted at sea), more sophisticated steam engines, and advances in metallurgy
History of ferrous metallurgy
The history of ferrous metallurgy began far back in prehistory. The earliest surviving iron artifacts, from the 5th millennium BC in Iran and 2nd millennium BC in China, were made from meteoritic iron-nickel. It is not known when or where the smelting of iron from ores began, but by the end of the...

 which made steel shipbuilding possible.

The rapid pace of change in the ironclad period meant that many ships were obsolete as soon as they were complete, and that naval tactics were in a state of flux. Many ironclads were built to make use of the ram
Naval ram
A naval ram was a weapon carried by varied types of ships, dating back to antiquity. The weapon consisted of an underwater prolongation of the bow of the ship to form an armoured beak, usually between six and twelve feet in length...

 or the torpedo
Torpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...

, which a number of naval designers considered the crucial weapons of naval combat. There is no clear end to the ironclad period, but towards the end of the 1890s the term ironclad dropped out of use. New ships were increasingly constructed to a standard pattern and designated battleships or armored cruiser
Armored cruiser
The armored cruiser was a type of warship of the late 19th and early 20th centuries. Like other types of cruiser, the armored cruiser was a long-range, independent warship, capable of defeating any ship apart from a battleship, and fast enough to outrun any battleships it encountered.The first...

s.

Before the ironclad


The ironclad became technically feasible and tactically necessary because of developments in shipbuilding in the first half of the 19th century. According to naval historian J. Richard Hill
J. Richard Hill
Rear Admiral John Richard Hill is a retired rear-admiral in the Royal Navy, a former chief executive of the Middle Temple, author, and editor of many books on naval affairs.-Early life and education:...

: "The (ironclad) had three chief characteristics: a metal-skinned hull, steam propulsion and a main armament of guns capable of firing explosive shells. It is only when all three characteristics are present that a fighting ship can properly be called an ironclad." Each of these developments was introduced separately in the decade before the first ironclads.

Steam propulsion



In the 18th and early 19th centuries fleets had relied on two types of major warship, the ship of the line
Ship of the line
A ship of the line was a type of naval warship constructed from the 17th through the mid-19th century to take part in the naval tactic known as the line of battle, in which two columns of opposing warships would manoeuvre to bring the greatest weight of broadside guns to bear...

 and the frigate
Frigate
A frigate is any of several types of warship, the term having been used for ships of various sizes and roles over the last few centuries.In the 17th century, the term was used for any warship built for speed and maneuverability, the description often used being "frigate-built"...

. The first major change to these types was the introduction of steam power for propulsion
Marine propulsion
Marine propulsion is the mechanism or system used to generate thrust to move a ship or boat across water. While paddles and sails are still used on some smaller boats, most modern ships are propelled by mechanical systems consisting a motor or engine turning a propeller, or less frequently, in jet...

. While paddle steamer
Paddle steamer
A paddle steamer is a steamship or riverboat, powered by a steam engine, using paddle wheels to propel it through the water. In antiquity, Paddle wheelers followed the development of poles, oars and sails, where the first uses were wheelers driven by animals or humans...

 warships had been used from the 1830s onwards, steam propulsion only became suitable for major warships after the adoption of the screw propeller in the 1840s.

Steam-powered screw frigates were built in the mid-1840s, and at the end of the decade the French Navy
French Navy
The French Navy, officially the Marine nationale and often called La Royale is the maritime arm of the French military. It includes a full range of fighting vessels, from patrol boats to a nuclear powered aircraft carrier and 10 nuclear-powered submarines, four of which are capable of launching...

 introduced steam power to its line of battle
Line of battle
In naval warfare, the line of battle is a tactic in which the ships of the fleet form a line end to end. A primitive form had been used by the Portuguese under Vasco Da Gama in 1502 near Malabar against a Muslim fleet.,Maarten Tromp used it in the Action of 18 September 1639 while its first use in...

. The desire for change came from the ambition of Napoleon III to gain greater influence in Europe, which required a challenge to the British at sea. The first purpose-built steam battleship was the 90-gun Le Napoléon
Le Napoléon (1850)
The Napoléon was a 90-gun ship of the line of the French Navy, and the very first purpose-built steam battleship in the world . She is also considered the first true steam battleship, and the first screw battleship ever . Launched in 1850, she was the lead ship of a class of 9 battleships, all...

 in 1850. Le Napoléon was armed as a conventional ship-of-the-line, but her steam engines could give her a speed of 12 knots (22 km/h), regardless of the wind conditions: a potentially decisive advantage in a naval engagement.

The introduction of the steam ship-of-the-line led to a building competition between France and Britain
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...

. Eight sister-ships to Le Napoléon were built in France over a period of ten years, but the United Kingdom soon managed to take the lead in production. Altogether, France built ten new wooden steam battleships and converted 28 from older ships of the line, while the United Kingdom built 18 and converted 41.

Explosive shells




The era of the wooden steam ship-of-the-line was brief, because of new, more powerful naval guns. In the 1820s and 1830s, warships began to mount increasingly heavy guns, replacing 18- and 24-pounder guns with 32-pounders on sailing ships-of-the-line and introducing 68-pounders on steamers. Then, the first shell guns
Shell (projectile)
A shell is a payload-carrying projectile, which, as opposed to shot, contains an explosive or other filling, though modern usage sometimes includes large solid projectiles properly termed shot . Solid shot may contain a pyrotechnic compound if a tracer or spotting charge is used...

 firing explosive shells were introduced following their development by the French Général Henri-Joseph Paixhans
Henri-Joseph Paixhans
Henri-Joseph Paixhans was a French artillery officer of the beginning of the 19th century.Henri-Joseph Paixhans graduated from the École Polytechnique...

, and by the 1840s were part of the standard armament for naval powers including the French Navy
French Navy
The French Navy, officially the Marine nationale and often called La Royale is the maritime arm of the French military. It includes a full range of fighting vessels, from patrol boats to a nuclear powered aircraft carrier and 10 nuclear-powered submarines, four of which are capable of launching...

, Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

, Imperial Russian Navy
Imperial Russian Navy
The Imperial Russian Navy refers to the Tsarist fleets prior to the February Revolution.-First Romanovs:Under Tsar Mikhail Feodorovich, construction of the first three-masted ship, actually built within Russia, was completed in 1636. It was built in Balakhna by Danish shipbuilders from Holstein...

 and United States Navy
United States Navy
The United States Navy is the naval warfare service branch of the United States Armed Forces and one of the seven uniformed services of the United States. The U.S. Navy is the largest in the world; its battle fleet tonnage is greater than that of the next 13 largest navies combined. The U.S...

. It is often held that the power of explosive shells to smash wooden hulls, as demonstrated by the Russian destruction of a Turkish
Ottoman Empire
The Ottoman EmpireIt was usually referred to as the "Ottoman Empire", the "Turkish Empire", the "Ottoman Caliphate" or more commonly "Turkey" by its contemporaries...

 squadron at the Battle of Sinope, spelled the end of the wooden-hulled warship. The more practical threat to wooden ships was from conventional cannon firing red-hot shot, which could lodge in the hull of a wooden ship and cause a fire or ammunition explosion. Some navies even experimented with hollow shot filled with molten metal for extra incendiary power.

Iron armor




Following the demonstration of the power of explosive shells against wooden ships at the Battle of Sinop
Battle of Sinop
The Battle of Sinop, or the Battle of Sinope, took place on 30 November 1853 at Sinop, a sea port in northern Anatolia, when Imperial Russian warships struck and annihilated a patrol force of Ottoman ships anchored in the harbor...

, and fearing that his own ships would be vulnerable to the Paixhans guns of Russian fortifications in the Crimean War
Crimean War
The Crimean War was a conflict fought between the Russian Empire and an alliance of the French Empire, the British Empire, the Ottoman Empire, and the Kingdom of Sardinia. The war was part of a long-running contest between the major European powers for influence over territories of the declining...

, Emperor Napoleon III ordered the development of light-draft floating batteries, equipped with heavy guns and protected by heavy armor. Experiments made during the first half of 1854 proved highly satisfactory, and on 17 July 1854, the French communicated to the British Government that a solution had been found to make gun-proof vessels and that plans would be communicated. After tests in September 1854, the British Admiralty agreed to build five armored floating batteries on the French plans.

‎ ‎
The French floating batteries
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 during the Great Siege of Gibraltar....

 were deployed in 1855 as a supplement to the wooden steam battle fleet in the Crimean War
Crimean War
The Crimean War was a conflict fought between the Russian Empire and an alliance of the French Empire, the British Empire, the Ottoman Empire, and the Kingdom of Sardinia. The war was part of a long-running contest between the major European powers for influence over territories of the declining...

. The role of the battery was to assist unarmored mortar and gunboats bombarding shore fortifications. The French used three of their ironclad batteries (Lave, Tonnante and Dévastation) in 1855 against the defenses at the Battle of Kinburn (1855)
Battle of Kinburn (1855)
The Battle of Kinburn/Kil-Bouroun was a naval engagement during the final stage of the Crimean War. It took place on the tip of the Kinburn Peninsula on 17 October 1855...

 on the Black Sea
Black Sea
The Black Sea is bounded by Europe, Anatolia and the Caucasus and is ultimately connected to the Atlantic Ocean via the Mediterranean and the Aegean seas and various straits. The Bosphorus strait connects it to the Sea of Marmara, and the strait of the Dardanelles connects that sea to the Aegean...

, where they were effective against Russian shore defences. They would later be used again during the Italian war
Second Italian War of Independence
The Second War of Italian Independence, Franco-Austrian War, Austro-Sardinian War, or Austro-Piedmontese War , was fought by Napoleon III of France and the Kingdom of Piedmont-Sardinia against the Austrian Empire in 1859...

 in the Adriatic in 1859. The British floating batteries Glatton and Meteor arrived too late to participate to the action at Kinburn. The British plan to use their floating armoured batteries in the Baltic Sea
Baltic Sea
The Baltic Sea is a brackish mediterranean sea located in Northern Europe, from 53°N to 66°N latitude and from 20°E to 26°E longitude. It is bounded by the Scandinavian Peninsula, the mainland of Europe, and the Danish islands. It drains into the Kattegat by way of the Øresund, the Great Belt and...

 against Kronstadt
Kronstadt
Kronstadt , also spelled Kronshtadt, Cronstadt |crown]]" and Stadt for "city"); is a municipal town in Kronshtadtsky District of the federal city of St. Petersburg, Russia, located on Kotlin Island, west of Saint Petersburg proper near the head of the Gulf of Finland. Population: It is also...

 was influential in causing the Russians to sue for peace.

The batteries have a claim to the title of the first ironclad warships but they were capable of only 4 knots (7 km/h) under their own power: they operated under their own power at the Battle of Kinburn, but had to be towed for long range transit. They were also arguably marginal to the work of the navy. The brief success of the floating ironclad batteries convinced France to begin work on armored warships for their battlefleet.

Early ironclad ships and battles


By the end of the 1850s it was clear that France was unable to match British building of steam warships, and to regain the strategic initiative a dramatic change was required. The result was the first ocean-going ironclad, the La Gloire
French battleship La Gloire
The French Navy's La Gloire was the first ocean-going ironclad battleship in history.She was developed following the Crimean War, in response to new developments in naval gun technology, especially the Paixhans guns and rifled guns, which used explosive shells with increased destructive power...

, begun in 1857 and launched in 1859.

La Gloires wooden hull was modelled on that of a steam ship of the line, reduced to one deck, sheathed in iron plates 4.5 inches (110 mm) thick. She was propelled by a steam engine, driving a single screw propeller for a speed of 13 knots (24 km/h). She was armed with thirty-six 6.4 inches (162.6 mm) rifled guns. France proceeded to construct 16 ironclad warships, including two more sister ships to La Gloire, and the only two-decked broadside ironclads ever built, Magenta and Solferino
Solferino (1861)
Solférino was a broadside ironclad warship of the French Navy, the second unit of the Magenta class, designed by Dupuy de Lôme and launched in 1861. She was named in honour of the Battle of Solferino....

.

The Royal Navy had not been keen to sacrifice their advantage in steam ships of the line, but was determined that the first British iron ship would outmatch the French ships in every respect, particularly speed. A fast ship would have the advantage of being able to choose a range of engagement which could make her invulnerable to enemy fire. The British specification was more a large, powerful frigate
Frigate
A frigate is any of several types of warship, the term having been used for ships of various sizes and roles over the last few centuries.In the 17th century, the term was used for any warship built for speed and maneuverability, the description often used being "frigate-built"...

 than a ship-of-the-line. The requirement for speed meant a very long vessel, which had to be built from iron. The resulting vessel was Warrior
HMS Warrior (1860)
HMS Warrior was the first iron-hulled, armour-plated warship, built for the Royal Navy in response to the first ironclad warship, the French Gloire, launched a year earlier....

, built and launched in 1860. Warrior was a successful design; her weapons and armor were more effective than that of La Gloire, and with the largest set of steam engines yet fitted to a ship she could steam at 14.3 knots (26.5 km/h).

By 1862, navies across Europe had adopted ironclads. Britain and France each had sixteen either completed or under construction, though the British vessels were larger. Austria, Italy, Russia, and Spain were also building ironclads. However, the first battles using the new ironclad ships involved neither Britain nor France, and involved ships markedly different from the broadside-firing, masted designs of La Gloire and Warrior. The use of ironclads by both sides in the American Civil War, and the clash of the Italian and Austrian fleets at the Battle of Lissa
Battle of Lissa (1866)
The Battle of Lissa took place on 20 July 1866 in the Adriatic Sea near the Dalmatian island of Lissa and was a decisive victory for an outnumbered Austrian Empire force over a superior Italian force...

, had an important influence on the development of ironclad design.

First battles between ironclads: the U.S. Civil War



The first use of ironclads in action came in the U.S. Civil War
American Civil War
The American Civil War was a civil war fought in the United States of America. In response to the election of Abraham Lincoln as President of the United States, 11 southern slave states declared their secession from the United States and formed the Confederate States of America ; the other 25...

. The U.S. Navy at the time the war broke out had no ironclads, its most powerful ships being six steam-powered unarmoured frigates. Since the bulk of the Navy remained loyal to the Union, the Confederacy sought to gain advantage in the naval conflict by acquiring modern armored ships. In May 1861, the Confederate Congress voted that $2 million be appropriated for the purchase of ironclads from overseas, and in July and August 1861 the Confederacy started work on construction and converting wooden ships.

On 12 October 1861, the CSS Manassas
CSS Manassas
CSS Manassas, formerly the steam icebreaker Enoch Train, was built as a twin-screw towboat at Medford, Massachusetts, by James O. Curtis in 1855. A New Orleans commission merchant, Captain John A...

 became the first ironclad to enter combat, when she fought Union warships on the Mississippi during the Battle of the Head of Passes
Battle of the Head of Passes
The Battle of the Head of Passes was a bloodless naval battle of the American Civil War. It was a naval raid made by the Confederate river defense fleet, also known as the “mosquito fleet” in the local media, on ships of the Union Blockade squadron anchored at the Head of Passes...

. She had been converted from a commercial vessel in New Orleans for river and coastal fighting. In February 1862, the larger CSS Virginia
CSS Virginia
CSS Virginia was the first steam-powered ironclad warship of the Confederate States Navy, built during the first year of the American Civil War; she was constructed as a casemate ironclad using the raised and cut down original lower hull and steam engines of the scuttled . Virginia was one of the...

 (Merrimack) joined the Confederate Navy, having been rebuilt at Norfolk
Norfolk Naval Shipyard
The Norfolk Naval Shipyard, often called the Norfolk Navy Yard and abbreviated as NNSY, is a U.S. Navy facility in Portsmouth, Virginia, for building, remodeling, and repairing the Navy's ships. It's the oldest and largest industrial facility that belongs to the U.S. Navy as well as the most...

. As , Virginia originally was a conventional warship made of wood, but she was reconstructed with an iron-covered casemate when she entered the Confederate navy. By this time, the Union had completed seven ironclad gunboats of the City
City class ironclad
The Pook Turtles, or City class gunboats to use their semi-official name, were war vessels intended for service on the Mississippi River during the American Civil War. They were also sometimes referred to as "Eads gunboats." The labels are applied to seven vessels of uniform design built from...

 class, and was about to complete the USS Monitor
USS Monitor
USS Monitor was the first ironclad warship commissioned by the United States Navy during the American Civil War. She is most famous for her participation in the Battle of Hampton Roads on March 9, 1862, the first-ever battle fought between two ironclads...

, an innovative design proposed by the Swedish inventor John Ericsson
John Ericsson
John Ericsson was a Swedish-American inventor and mechanical engineer, as was his brother Nils Ericson. He was born at Långbanshyttan in Värmland, Sweden, but primarily came to be active in England and the United States...

. The Union was also building a large armored frigate, the USS New Ironsides
USS New Ironsides (1862)
USS New Ironsides was a wooden-hulled broadside ironclad built for the United States Navy during the American Civil War. The ship spent most of her career blockading the Confederate ports of Charleston, South Carolina, and Wilmington, North Carolina in 1863–65...

, and the smaller USS Galena
USS Galena (1862)
USS Galena — an ironclad screw steamer — was one of the first three ironclads, each of a different design, built by the Union Navy during the American Civil War....

.

The first battle between ironclads happened on 9 March 1862, as the armored Monitor was deployed to protect the Union's wooden fleet from the ironclad ram Virginia and other Confederate warships. In this engagement, the second day of the Battle of Hampton Roads
Battle of Hampton Roads
The Battle of Hampton Roads, often referred to as either the Battle of the Monitor and Merrimack or the Battle of Ironclads, was the most noted and arguably most important naval battle of the American Civil War from the standpoint of the development of navies...

, the two ironclads repeatedly tried to ram one another while shells bounced off their armor. The battle attracted attention worldwide, making it clear that the wooden warship was now out of date, with the ironclads destroying them easily.

The Civil War saw more ironclads built by both sides, and they played an increasing role in the naval war alongside the unarmored warships, commerce raiders and blockade runners. The Union built a large fleet of fifty monitors
Monitor (warship)
A monitor was a class of relatively small warship which was neither fast nor strongly armoured but carried disproportionately large guns. They were used by some navies from the 1860s until the end of World War II, and saw their final use by the United States Navy during the Vietnam War.The monitors...

 modeled on their namesake. The Confederacy built ships designed as smaller versions of the Virginia, many of which saw action, but their attempts to buy ironclads overseas were frustrated as European nations confiscated ships being built for the Confederacy — especially in Russia, the only country to openly support the Union through the war. Only CSS Stonewall was completed, and she arrived in American waters just in time for the end of the war.

Through the remainder of the war, ironclads saw action in the Union's attacks on Confederate ports. Seven Union monitors, including USS Montauk
USS Montauk (1862)
The first USS Montauk was a single-turreted monitor in the United States Navy during the American Civil War.It saw action throughout the war and was used as the floating prison for the conspirators in the Abraham Lincoln assassination and was the site of the autopsy and identification of assassin...

, as well as two other ironclads, the ironclad frigate New Ironsides and a light-draft Keokuk, participated in the failed attack on Charleston
Charleston, South Carolina
Charleston is the second largest city in the U.S. state of South Carolina. It was made the county seat of Charleston County in 1901 when Charleston County was founded. The city's original name was Charles Towne in 1670, and it moved to its present location from a location on the west bank of the...

; one was sunk. Two small ironclads, CSS Palmetto State
CSS Palmetto State
CSS Palmetto State, an ironclad ram, was built by Cameron and Co., Charleston, South Carolina in January 1862, under the supervision of Flag Officer D. N. Ingraham, CSN. She was readied for service by September 1862 when Lieutenant Commander John Rutledge, CSN, was placed in command. Her armor was...

 and CSS Chicora
CSS Chicora
CSS Chicora was a Confederate ironclad ram that fought in the American Civil War. She was built under contract at Charleston, South Carolina in 1862. James M. Eason built her to John L...

 participated in the defence of the harbor. For the later attack at Mobile Bay
Battle of Mobile Bay
The Battle of Mobile Bay of August 5, 1864, was an engagement of the American Civil War in which a Federal fleet commanded by Rear Adm. David G. Farragut, assisted by a contingent of soldiers, attacked a smaller Confederate fleet led by Adm...

, the Union assembled four monitors as well as 11 wooden ships, facing the CSS Tennessee
CSS Tennessee (1863)
CSS Tennessee, an ironclad ram, was built at Selma, Alabama, where she was commissioned on February 16, 1864, Lieutenant James D. Johnston, CSN, in command. towed her to Mobile where she was fitted out for action....

, the Confederacy's most powerful ironclad and the gunboats CSS Morgan
CSS Morgan
CSS Morgan was a partially armored gunboat of the Confederate States Navy in the American Civil War.Morgan was built at Mobile, Alabama in 1861-62. She operated in the waters around Mobile from the time of her completion early in 1862 to the close of hostilities. One reference of October 1862 gave...

, CSS Gaines
CSS Gaines
CSS Gaines was a wooden side wheel gunboat constructed by the Confederates at Mobile, Alabama during 1861-62. The ship was hastily built with unseasoned wood, which was partially covered with 2-inch iron plating. Gaines resembled CSS Morgan except that she had high pressure boilers. Operating in...

, CSS Selma
CSS Selma
CSS Selma was a steamship in the Confederate States Navy during the American Civil War.Selma was a coastwise packet built at Mobile, Alabama for the Mobile Mail Line in 1856. Little doubt now remains that she was originally named Florida...

.

On the western front, the Union built a formidable force of river ironclads, beginning with several converted riverboats and then contracting engineer James Eads of St. Louis, Missouri
Missouri
Missouri is a US state located in the Midwestern United States, bordered by Iowa, Illinois, Kentucky, Tennessee, Arkansas, Oklahoma, Kansas and Nebraska. With a 2010 population of 5,988,927, Missouri is the 18th most populous state in the nation and the fifth most populous in the Midwest. It...

 to build the "City" class ironclads. These excellent ships were built with twin engines and a central paddle wheel, all protected by an armored casement. They had a shallow draft, allowing them to journey up smaller tributaries, and were very well suited for river operations. Eads also produced monitors for use on the rivers, the first two of which differed from the ocean going monitors in that they contained a paddle wheel (the USS Neosho (1863)
USS Neosho (1863)
USS Neosho was a ironclad river monitor laid down for the Union Navy in the summer of 1862 during the American Civil War. She was named after the Neosho River that flowed through Kansas and Oklahoma. After completion in mid-1863 the ship spent time patrolling the Mississippi River against...

 and USS Osage (1863)
USS Osage (1863)
The first USS Osage was a single-turreted Neosho-class river monitor named after the American Indian tribe living in the Missouri area ....

).
Arguably Eads vessels were some of the better ironclads of the Western Flotilla, but there were a number of other vessels that served valiantly with the fleet. All were of varying design, some more successful than others, and some were similar to standard riverboats but with armored side-mounted paddle wheels. All were armed with various smoothbore and some rifled guns.

The Union ironclads played an important role in the Mississippi and tributaries by providing tremendous fire upon Confederate forts, installations and vessels with relative impunity to enemy fire. They were not as heavily armored as the ocean going monitors of the Union, but they were adequate for their intended use. More Western Flotilla Union ironclads were sunk by torpedoes (mines) than by enemy fire, and the most damaging fire for the Union ironclads was from shore installations, not Confederate vessels.

Lissa: First fleet battle



The first fleet battle, and the first ocean battle, involving ironclad warships was the Battle of Lissa
Battle of Lissa (1866)
The Battle of Lissa took place on 20 July 1866 in the Adriatic Sea near the Dalmatian island of Lissa and was a decisive victory for an outnumbered Austrian Empire force over a superior Italian force...

 in 1866. Waged between the Austrian
Austrian Empire
The Austrian Empire was a modern era successor empire, which was centered on what is today's Austria and which officially lasted from 1804 to 1867. It was followed by the Empire of Austria-Hungary, whose proclamation was a diplomatic move that elevated Hungary's status within the Austrian Empire...

 and Italian
Regia Marina
The Regia Marina dates from the proclamation of the Kingdom of Italy in 1861 after Italian unification...

 navies, the battle pitted combined fleets of wooden frigate
Frigate
A frigate is any of several types of warship, the term having been used for ships of various sizes and roles over the last few centuries.In the 17th century, the term was used for any warship built for speed and maneuverability, the description often used being "frigate-built"...

s and corvette
Corvette
A corvette is a small, maneuverable, lightly armed warship, originally smaller than a frigate and larger than a coastal patrol craft or fast attack craft , although many recent designs resemble frigates in size and role...

s and ironclad warships on both sides in the largest naval battle between the battles of Navarino
Battle of Navarino
The naval Battle of Navarino was fought on 20 October 1827, during the Greek War of Independence in Navarino Bay , on the west coast of the Peloponnese peninsula, in the Ionian Sea. A combined Ottoman and Egyptian armada was destroyed by a combined British, French and Russian naval force...

 and Tsushima
Battle of Tsushima
The Battle of Tsushima , commonly known as the “Sea of Japan Naval Battle” in Japan and the “Battle of Tsushima Strait”, was the major naval battle fought between Russia and Japan during the Russo-Japanese War...

.

The Italian fleet consisted of 12 ironclads and a similar number of wooden warships, escorting transports which carried troops intending to land on the Adriatic island of Lissa. Among the Italian ironclads were seven broadside ironclad frigates, four smaller ironclads, and the newly built Affondatore — a double-turretted ram. Opposing them, the Austrian navy had seven ironclad frigates.

The Austrians believed their ships to have less effective guns than their enemy, so decided to engage the Italians at close range and ram the enemy. The Austrian fleet formed into an arrowhead formation with the ironclads in the first line, charging at the Italian ironclad squadron. In the melée which followed both sides were frustrated by the lack of damage inflicted by guns, and by the difficulty of ramming—nonetheless, the effective ramming attack being made by the Austrian flagship against the Italian attracted great attention in following years.

The superior Italian fleet lost its two ironclads, Re d'Italia and Palestro, while the Austrian unarmoured screw two-decker Kaiser remarkably survived close actions with four Italian ironclads. The battle ensured the popularity of the ram as a weapon in European ironclads for many years, and the victory won by Austria established it as the predominant naval power in the Adriatic.

The battles of the American Civil War and at Lissa were very influential on the designs and tactics of the ironclad fleets that followed. In particular, it taught a generation of naval officers the misleading lesson that ramming was the best way to sink enemy ironclads.

Armament and tactics


The adoption of iron armor meant that the traditional naval armament of dozens of light cannon became useless, since their shot would bounce off an armored hull. To penetrate armor, increasingly heavy guns were mounted on ships; nevertheless, the view that ramming
Naval ram
A naval ram was a weapon carried by varied types of ships, dating back to antiquity. The weapon consisted of an underwater prolongation of the bow of the ship to form an armoured beak, usually between six and twelve feet in length...

 was the only way to sink an ironclad became widespread. The increasing size and weight of guns also meant a movement away from the ships mounting many guns broadside, in the manner of a ship-of-the-line, towards a handful of guns in turrets for all-round fire.

Ram craze


From the 1860s to the 1880s many naval designers believed that the development of the ironclad meant that the ram
Naval ram
A naval ram was a weapon carried by varied types of ships, dating back to antiquity. The weapon consisted of an underwater prolongation of the bow of the ship to form an armoured beak, usually between six and twelve feet in length...

 was again the most important weapon in naval warfare. With steam power freeing ships from the wind, and armor making them invulnerable to shellfire, the ram seemed to offer the opportunity to strike a decisive blow.

The scant damage inflicted by the guns of Monitor and Virginia at Battle of Hampton Roads
Battle of Hampton Roads
The Battle of Hampton Roads, often referred to as either the Battle of the Monitor and Merrimack or the Battle of Ironclads, was the most noted and arguably most important naval battle of the American Civil War from the standpoint of the development of navies...

 and the spectacular but lucky success of the Austrian flagship Ferdinand Max sinking the Italian Re d'Italia at Lissa
Battle of Lissa (1866)
The Battle of Lissa took place on 20 July 1866 in the Adriatic Sea near the Dalmatian island of Lissa and was a decisive victory for an outnumbered Austrian Empire force over a superior Italian force...

 gave strength to the ramming craze. From the early 1870s to early 1880s most British naval officers thought that guns were about to be replaced as the main naval armament by the ram. Those who noted the tiny number of ships that had actually been sunk by ramming struggled to be heard.

The revival of ramming had a significant effect on naval tactics. Since the 17th century the predominant tactic of naval warfare had been the line of battle
Line of battle
In naval warfare, the line of battle is a tactic in which the ships of the fleet form a line end to end. A primitive form had been used by the Portuguese under Vasco Da Gama in 1502 near Malabar against a Muslim fleet.,Maarten Tromp used it in the Action of 18 September 1639 while its first use in...

, where a fleet formed a long line to give it the best fire from its broadside
Broadside
A broadside is the side of a ship; the battery of cannon on one side of a warship; or their simultaneous fire in naval warfare.-Age of Sail:...

 guns. This tactic was totally unsuited to ramming, and the ram threw fleet tactics into disarray. The question of how an ironclad fleet should deploy in battle to make best use of the ram was never tested in battle, and if it had been, combat might have shown that rams could only be used against ships which were already stopped dead in the water.

The ram finally fell out of favour in the 1880s, as the same effect could be achieved with a torpedo, with less vulnerability to quick-firing guns.

Development of naval guns


The armament of ironclads tended to become concentrated in a small number of powerful guns capable of penetrating the armor of enemy ships at range; calibre and weight of guns increased markedly to achieve greater penetration. Throughout the ironclad era navies also grappled with the complexities of rifled
Rifling
Rifling is the process of making helical grooves in the barrel of a gun or firearm, which imparts a spin to a projectile around its long axis...

 versus smoothbore
Smoothbore
A smoothbore weapon is one which has a barrel without rifling. Smoothbores range from handheld firearms to powerful tank guns and large artillery mortars.-History of firearms and rifling:...

 guns and breech-loading versus muzzle-loading.
HMS Warrior
HMS Warrior (1860)
HMS Warrior was the first iron-hulled, armour-plated warship, built for the Royal Navy in response to the first ironclad warship, the French Gloire, launched a year earlier....

 carried a mixture of 110-pounder 7 inch (180 mm) breech-loading rifles and more traditional 68-pounder smoothbore guns. Warrior highlighted the challenges of picking the right armament; the breech-loaders she carried, designed by Sir William Armstrong
William George Armstrong, 1st Baron Armstrong
William George Armstrong, 1st Baron Armstrong CB, FRS was an effective Tyneside industrialist who founded the Armstrong Whitworth manufacturing empire.-Early life:...

, were intended to be the next generation of heavy armament for the Royal Navy, but were shortly withdrawn from service.

Breech-loading guns seemed to offer important advantages. A breech-loader could be reloaded without moving the gun, a lengthy process particularly if the gun then needed to be re-aimed. The Warriors Armstrong gun
Armstrong Gun
The term Armstrong Gun was primarily used to describe the unique design of the rifled breech-loading field and heavy guns designed by Sir William Armstrong and manufactured in England from 1855 by the Elswick Ordnance Company and the Royal Arsenal at Woolwich...

s also had the virtue of being lighter than an equivalent smoothbore and, because of their rifling, more accurate. Nonetheless, the design was rejected because of problems which plagued breech-loaders for decades.

The weakness of the breech-loader was the obvious problem of sealing the breech. All guns are powered by the explosive conversion of gunpowder
Gunpowder
Gunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...

 into gas. This explosion propels the shot or shell out of the front of the gun, but also imposes great stresses on the gun-barrel. If the breech — which experiences some of the greatest forces in the gun — is not entirely secure, then there is a risk that either gas will discharge through the breech or that the breech will break. This in turn reduces the muzzle velocity
Muzzle velocity
Muzzle velocity is the speed a projectile has at the moment it leaves the muzzle of the gun. Muzzle velocities range from approximately to in black powder muskets , to more than in modern rifles with high-performance cartridges such as the .220 Swift and .204 Ruger, all the way to for tank guns...

 of the weapon and can also endanger the gun crew. The Warriors Armstrong guns suffered from both problems; the shells were unable to penetrate the 4.5 in (118 mm) armor of La Gloire, while sometimes the screw which closed the breech flew backwards out of the gun on firing. Similar problems were experienced with the breech-loading guns which became standard in the French and German navies.

These problems influenced the British to equip ships with muzzle-loading weapons of increasing power until the 1880s. After a brief introduction of 100-pounder or 9.5-inch (240 mm) smoothbore Somerset Gun, which weighed 6.5 tons
Long ton
Long ton is the name for the unit called the "ton" in the avoirdupois or Imperial system of measurements, as used in the United Kingdom and several other Commonwealth countries. It has been mostly replaced by the tonne, and in the United States by the short ton...

 (6.6 t), the Admiralty introduced 7-inch (178 mm) rifled guns, weighing 7 tons. These were followed by a series of increasingly mammoth weapons—guns weighing 12, 25, 25, 38 and finally 81 tons, with calibre increasing from 8-inch (203 mm) to 16-inch (406 mm).

The decision to retain muzzle-loaders until the 1880s has been criticised by historians. However, at least until the late 1870s, the British muzzle-loaders had superior performance in terms of both range and rate of fire than the French and Prussian breech-loaders, which suffered from the same problems as had the first Armstrong guns.

From 1875 onwards, the balance between breech- and muzzle-loading changed. Captain de Bange invented a method of reliably sealing a breech, adopted by the French in 1873. Just as compellingly, the growing size of naval guns made muzzle-loading much more complicated. With guns of such size there was no prospect of hauling in the gun for re-loading, or even re-loading by hand, and complicated hydraulic systems were required for re-loading the gun outside the turret without exposing the crew to enemy fire. In 1882, the 81-ton, 16-inch (406 mm) guns of HMS Inflexible
HMS Inflexible (1876)
HMS Inflexible was a Victorian ironclad battleship carrying her main armament in centrally placed turrets. The ship was constructed in the 1870s for the Royal Navy to oppose the perceived growing threat from the Italian Regia Marina in the Mediterranean.The Italian Navy had started constructing a...

 fired only once every 11 minutes while bombarding Alexandria
Alexandria
Alexandria is the second-largest city of Egypt, with a population of 4.1 million, extending about along the coast of the Mediterranean Sea in the north central part of the country; it is also the largest city lying directly on the Mediterranean coast. It is Egypt's largest seaport, serving...

 during the Urabi Revolt
Urabi Revolt
The Urabi Revolt or Orabi Revolt , also known as the Orabi Revolution, was an uprising in Egypt in 1879-82 against the Khedive and European influence in the country...

. The 100-ton, 450 mm (17.72 inch) guns of Duilio
Italian ironclad Caio Duilio
Caio Duilio was the lead ship in a class of two ironclad battleships built in Italy for the Regia Marina in the 1870s. A revolutionary design fitted with the largest guns available, 100-ton 450 mm calibre muzzle-loading guns, she and her sister ship were regarded as the most powerful warships...

 could each fire a round every 15 minutes.

In the Royal Navy, the switch to breech-loaders was finally made in 1879; as well as the significant advantages in terms of performance, opinion was swayed by an explosion on board HMS Thunderer
HMS Thunderer (1872)
HMS Thunderer was a British Royal Navy Devastation-class battleship.Thunder was an ironclad turret ship designed by Edward James Reed with revolving turrets, launched in 1872...

 caused by a gun being double-loaded, a problem which could only happen with a muzzle-loading gun.

The calibre and weight of guns could only increase so far. The larger the gun, the slower it would be to load, the greater the stresses on the ship's hull, and the less the stability of the ship. The size of the gun peaked in the 1880s, with some of the heaviest calibres of gun ever used at sea. HMS Benbow
HMS Benbow (1885)
HMS Benbow was a Victorian era Admiral-class battleship of the British Royal Navy, named for Admiral John Benbow.With the exception of her armament she was a repeat of HMS Anson and HMS Camperdown. The contract for her construction was awarded to Thames Ironworks, and stipulated delivery within...

 carried two 16.25-inch (413 mm) breech-loading guns
BL 16.25 inch Mk I naval gun
The Elswick BL 16.25 inch naval gun was an early British superheavy breech-loading naval gun, commonly known as the 110-ton gun or 111-ton gun.-Service:...

, each weighing 110 tons—no British battleship would ever carry guns as large. The Italian 450 mm (17.72 inch) guns would be larger than any gun fitted to a battleship until the 18.1-inch (460 mm)
40 cm/45 Type 94
The Japanese was the largest bore gun ever mounted on any warship. They were actually 46 cm guns, but were designated 40 cm in an effort to hide their true size.-Description:...

 armament of the Japanese Yamato class
Yamato class battleship
The were battleships of the Imperial Japanese Navy constructed and operated during World War II. Displacing at full load, the vessels were the heaviest and most powerfully armed battleships ever constructed. The class carried the largest naval artillery ever fitted to a warship, nine naval...

 of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...

.

Another method of increasing firepower was to vary the projectile fired or the nature of the propellant. Early ironclads used black powder
Gunpowder
Gunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...

, which expanded rapidly after combustion; this meant cannon
Cannon
A cannon is any piece of artillery that uses gunpowder or other usually explosive-based propellents to launch a projectile. Cannon vary in caliber, range, mobility, rate of fire, angle of fire, and firepower; different forms of cannon combine and balance these attributes in varying degrees,...

s had relatively short barrels, to prevent the barrel itself slowing the shell. The sharpness of the black powder explosion also meant that guns were subjected to extreme stress. One important step was to press the powder into pellets, allowing a slower, more controlled explosion and a longer barrel. A further step forward was the introduction of chemically different "brown powder" which combusted more slowly again. It also put less stress on the insides of the barrel, allowing guns to last longer and to be manufactured to tighter tolerances.

The development of smokeless powder
Smokeless powder
Smokeless powder is the name given to a number of propellants used in firearms and artillery which produce negligible smoke when fired, unlike the older gunpowder which they replaced...

, based on nitroglycerine or nitrocellulose, by the French inventor Paul Vielle
Paul Marie Eugène Vieille
Paul Marie Eugène Vieille ,a graduate of Ecole Polytechnique, was a French chemist and the inventor of modern nitrocellulose-based smokeless gunpowder in 1884. The new smokeless powder was three times as powerful as black powder for the same weight and left virtually no residues of combustion...

 in 1884 was a further step allowing smaller charges of propellant with longer barrels. The guns of the pre-Dreadnought battleships of the 1890s tended to be smaller in calibre compared to the ships of the 1880s, most often 12 in (305 mm), but progressively grew in length of barrel, making use of improved propellants to gain greater muzzle velocity.

The nature of the projectiles also changed during the ironclad period. Initially, the best armor-piercing projectile was a solid cast-iron shot. Later, shot of chilled iron
Chill (foundry)
A chill is an object used to promote solidification in a specific portion of a metal casting mold. Normally the metal in the mold cools at a certain rate relative to thickness of the casting. When the geometry of the molding cavity prevents directional solidification from occurring naturally, a...

, a harder iron alloy, gave better armor-piercing qualities. Eventually the armor-piercing shell
Armor-piercing shot and shell
An armor-piercing shell is a type of ammunition designed to penetrate armor. From the 1860s to 1950s, a major application of armor-piercing projectiles was to defeat the thick armor carried on many warships. From the 1920s onwards, armor-piercing weapons were required for anti-tank missions...

 was developed.

Broadside ironclads


The first British, French and Russian ironclads, in a logical development of warship design from the long preceding era of wooden ships of the line
Ship of the line
A ship of the line was a type of naval warship constructed from the 17th through the mid-19th century to take part in the naval tactic known as the line of battle, in which two columns of opposing warships would manoeuvre to bring the greatest weight of broadside guns to bear...

, carried their weapons in a single line along their sides and so were called "broadside
Broadside
A broadside is the side of a ship; the battery of cannon on one side of a warship; or their simultaneous fire in naval warfare.-Age of Sail:...

 ironclads." Both La Gloire
French battleship La Gloire
The French Navy's La Gloire was the first ocean-going ironclad battleship in history.She was developed following the Crimean War, in response to new developments in naval gun technology, especially the Paixhans guns and rifled guns, which used explosive shells with increased destructive power...

 and HMS Warrior
HMS Warrior (1860)
HMS Warrior was the first iron-hulled, armour-plated warship, built for the Royal Navy in response to the first ironclad warship, the French Gloire, launched a year earlier....

 were examples of this type. Because their armor was so heavy, they could only carry a single row of guns along the main deck on each side rather than a row on each deck.

A significant number of broadside ironclads were built in the 1860s, principally in Britain and France, but in smaller numbers by other powers including Italy, Austria, Russia and the United States. The advantages of mounting guns on both broadsides was that the ship could engage more than one adversary at a time, and the rigging did not impede the field of fire.

Broadside armament also had disadvantages, which became more serious as ironclad technology developed. Heavier guns to penetrate ever-thicker armor meant that fewer guns could be carried. Furthermore, the adoption of ramming as an important tactic meant the need for ahead and all-round fire. These problems led to broadside designs being superseded by designs that gave greater all-round fire, which included central-battery, turret, and barbette designs.

Turrets, batteries and barbettes



There were two main design options to the broadside. In one design, the guns were placed in an armoured casemate amidships: this arrangement was called the 'box-battery' or 'centre-battery'. In the other, the guns could be placed on a rotating platform to give them a broad field of fire; when fully armored, this arrangement was called a turret
Turret
In architecture, a turret is a small tower that projects vertically from the wall of a building such as a medieval castle. Turrets were used to provide a projecting defensive position allowing covering fire to the adjacent wall in the days of military fortification...

 and when partially armored or unarmored, a barbette
Barbette
A barbette is a protective circular armour feature around a cannon or heavy artillery gun. The name comes from the French phrase en barbette referring to the practice of firing a field gun over a parapet rather than through an opening . The former gives better angles of fire but less protection...

.

The centre-battery was the simpler and, during the 1860s and 1870s, the more popular method. Concentrating guns amidships meant the ship could be shorter and handier than a broadside type. The first full-scale centre-battery ship was HMS Bellerophon
HMS Bellerophon (1865)
HMS Bellerophon was a central battery ironclad built for the Royal Navy in the mid-1860s.-Design and description:In this ship, designed by Sir Edward Reed, the power-to-weight ratio was increased; the long rows of guns on the broadside were replaced by a small number of guns, centrally placed, of...

 of 1865; the French laid down centre-battery ironclads in 1865 which were not completed until 1870. Centre-battery ships often, but not always, had a recessed freeboard enabling some of their guns to fire directly ahead.

The turret made its debut with USS Monitor in 1862, with a type of turret designed by the Swedish engineer John Ericsson
John Ericsson
John Ericsson was a Swedish-American inventor and mechanical engineer, as was his brother Nils Ericson. He was born at Långbanshyttan in Värmland, Sweden, but primarily came to be active in England and the United States...

. A competing turret design was proposed by the British inventor Cowper Coles. Ericsson's turret turned on a central spindle, and Coles's turned on a ring of bearings. Turrets offered the maximum arc of fire from the guns, but there were significant problems with their use in the 1860s. The fire arc of a turret would be considerably limited by masts and rigging, so they were unsuited to use on the earlier ocean-going ironclads. The second problem was that turrets were extremely heavy—unless a ship was very large, the weight of the turrets meant a ship needed a low freeboard
Freeboard (nautical)
In sailing and boating, freeboardmeans the distance from the waterline to the upper deck level, measured at the lowest point of sheer where water can enter the boat or ship...

 or would suffer from stability problems. HMS Captain
HMS Captain (1869)
HMS Captain was an unsuccessful warship built for the Royal Navy due to public pressure. She was a masted turret ship, designed and built by a private contractor against the wishes of the Controller's department...

, designed by Coles as an example of how this circle could be squared
Squaring the circle
Squaring the circle is a problem proposed by ancient geometers. It is the challenge of constructing a square with the same area as a given circle by using only a finite number of steps with compass and straightedge...

, capsized in 1870. Her half-sister Monarch
HMS Monarch (1868)
HMS Monarch was the first sea-going warship to carry her guns in turrets, and the first British warship to carry guns of calibre.-Design:...

 was restricted to firing from her turrets only on the port and starboard beams. The third Royal Navy ship to combine turrets and masts was HMS Inflexible
HMS Inflexible (1876)
HMS Inflexible was a Victorian ironclad battleship carrying her main armament in centrally placed turrets. The ship was constructed in the 1870s for the Royal Navy to oppose the perceived growing threat from the Italian Regia Marina in the Mediterranean.The Italian Navy had started constructing a...

 of 1876, which carried two turrets on either side of the centre-line, allowing both to fire fore, aft and broadside.

A lighter alternative to the turret, particularly popular with the French navy, was the barbette. These were fixed armored towers which held a gun on a turntable. The crew was sheltered from direct fire, but vulnerable to plunging fire, for instance from shore emplacements. The barbette was lighter than the turret, needing less machinery and no roof armor—though nevertheless some barbettes were stripped of their armor plate to reduce the top-weight of their ships. The barbette became widely adopted in the 1880s, and with the addition of an armored 'gun-house', transformed into the turrets of the pre-Dreadnought battleships.

Torpedoes


The ironclad age saw the development of explosive torpedo
Torpedo
The modern torpedo is a self-propelled missile weapon with an explosive warhead, launched above or below the water surface, propelled underwater towards a target, and designed to detonate either on contact with it or in proximity to it.The term torpedo was originally employed for...

es as naval weapons, which helped complicate the design and tactics of ironclad fleets. The first torpedoes were static mines
Naval mine
A naval mine is a self-contained explosive device placed in water to destroy surface ships or submarines. Unlike depth charges, mines are deposited and left to wait until they are triggered by the approach of, or contact with, an enemy vessel...

, used extensively in the American Civil War. That conflict also saw the development of the spar torpedo
Spar torpedo
A spar torpedo is a weapon consisting of a bomb placed at the end of a long pole, or spar, and attached to a boat. The weapon is used by running the end of the spar into the enemy ship. Spar torpedoes were often equipped with a barbed spear at the end, so it would stick to wooden hulls...

, an explosive charge pushed against the hull of a warship by a small boat. For the first time, a large warship faced a serious threat from a smaller one—and given the relative inefficiency of shellfire against ironclads, the threat from the spar torpedo was taken seriously. The U.S. Navy converted four of its monitors to become turretless armored spar-torpedo vessels while under construction in 1864–5, but these vessels never saw action. Another proposal, the towed or 'Harvey' torpedo, involved an explosive on a line or outrigger; either to deter a ship from ramming or to make a torpedo attack by a boat less suicidal.

A more practical and influential weapon was the self-propelled or 'Whitehead
Robert Whitehead
Robert Whitehead was an English engineer. He developed the first effective self-propelled naval torpedo. His company, located in the Austrian naval centre in Fiume, was the world leader in torpedo development and production up to the First World War.- Early life:He was born the son of a...

' torpedo. Invented in 1868 and deployed in the 1870s, the Whitehead torpedo formed part of the armament of ironclads of the 1880s like HMS Inflexible and the Italian Duilio and Dandolo. The ironclad's vulnerability to the torpedo was a key part of the critique of armored warships made by the Jeune Ecole
Jeune Ecole
The Jeune École was a strategic naval concept developed during the 19th century. It advocated the use of small, powerfully equipped units to combat a larger battleship fleet, and commerce raiders capable of ending the trade of the rival nation...

 school of naval thought; it appeared that any ship armored enough to prevent destruction by gunfire would be slow enough to be easily caught by torpedo. In practice, however, the Jeune Ecole was only briefly influential and the torpedo formed part of the confusing mixture of weapons possessed by ironclads.

Armor and construction


The first ironclads were built on wooden or iron hulls, and protected by wrought iron armor backed by thick wooden planking. Ironclads were still being built with wooden hulls into the 1870s.

Hulls: iron, wood and steel


Using iron construction for warships offered advantages for the engineering of the hull. However, unarmored iron had many military disadvantages, and offered technical problems which kept wooden hulls in use for many years, particularly for long-range cruising warships.

Iron ships had first been proposed for military use in the 1820s. In the 1830s and 1840s France, Britain and the USA had all experimented with iron-hulled but unarmored gunboats and frigates. However, the iron-hulled frigate was abandoned by the end of the 1840s, because iron hulls were more vulnerable to solid shot; iron was more brittle than wood, and iron frames more likely to fall out of shape than wood.

The unsuitability of unarmored iron for warship hulls meant that iron was only adopted as a building material for battleships when protected by armor. However, iron gave the naval architect many advantages. Iron allowed larger ships and more flexible design, for instance the use of watertight bulkheads on the lower decks. Warrior, built of iron, was longer and faster than the wooden-hulled La Gloire. Iron could be produced to order and used immediately, in contrast to the need to give wood a long period of seasoning. And, given the large quantities of wood required to build a steam warship and the falling cost of iron, iron hulls were increasingly cost-effective. The main reason for the French use of wooden hulls for the ironclad fleet built in the 1860s was that the French iron industry could not supply enough, and the main reason why Britain built its handful of wooden-hulled ironclads was to make best use of hulls already started and wood already bought.

Wooden hulls continued to be used for long-range and smaller ironclads, because iron nevertheless had a significant disadvantage. Iron hulls suffered quick fouling
Fouling
Fouling refers to the accumulation of unwanted material on solid surfaces, most often in an aquatic environment. The fouling material can consist of either living organisms or a non-living substance...

 by marine life, slowing the ships down—manageable for a European battlefleet close to dry dock
Dry dock
A drydock is a narrow basin or vessel that can be flooded to allow a load to be floated in, then drained to allow that load to come to rest on a dry platform...

s, but a difficulty for long-range ships. The only solution was to sheath the iron hull first in wood and then in copper, a laborious and expensive process which made wooden construction remain attractive. Iron and wood were to some extent interchangeable: the Japanese Kongo and Hiei ordered in 1875 were sister-ships, but one was built of iron and the other of composite construction.

After 1872, steel started to be introduced as a material for construction. Compared to iron
Iron
Iron is a chemical element with the symbol Fe and atomic number 26. It is a metal in the first transition series. It is the most common element forming the planet Earth as a whole, forming much of Earth's outer and inner core. It is the fourth most common element in the Earth's crust...

, steel
Steel
Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

 allows for greater structural strength for a lower weight. The French Navy led the way with the use of steel in its fleet, starting with the Redoutable
French battleship Redoutable (1876)
Redoutable was a central battery and barbette ship of the French Navy. She was the first warship in the world to use steel as the principal building material....

, laid down in 1873 and launched in 1876. Redoutable nonetheless had wrought iron armor plate, and part of her exterior hull was iron rather than steel.

Even though Britain led the world in steel production, the Royal Navy was slow to adopt steel warships. The Bessemer process
Bessemer process
The Bessemer process was the first inexpensive industrial process for the mass-production of steel from molten pig iron. The process is named after its inventor, Henry Bessemer, who took out a patent on the process in 1855. The process was independently discovered in 1851 by William Kelly...

 for steel manufacture produced too many imperfections for large-scale use on ships. French manufacturers used the Siemens-Martin process to produce adequate steel, but British technology lagged behind. The first all-steel warships built by the Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 were the dispatch vessels Iris and Mercury, laid down in 1875 and 1876.

Armor and protection schemes


Iron-built ships used wood as part of their protection scheme. HMS Warrior was protected by 4.5 in (114 mm) of wrought iron
Wrought iron
thumb|The [[Eiffel tower]] is constructed from [[puddle iron]], a form of wrought ironWrought iron is an iron alloy with a very low carbon...

 backed by 15 in (381 mm) of teak
Teak
Teak is the common name for the tropical hardwood tree species Tectona grandis and its wood products. Tectona grandis is native to south and southeast Asia, mainly India, Indonesia, Malaysia, and Burma, but is naturalized and cultivated in many countries, including those in Africa and the...

, the strongest shipbuilding wood. The wood played two roles, preventing spalling and also preventing the shock of a hit damaging the structure of the ship. Later, wood and iron were combined in 'sandwich' armor, for instance in HMS Inflexible
HMS Inflexible (1876)
HMS Inflexible was a Victorian ironclad battleship carrying her main armament in centrally placed turrets. The ship was constructed in the 1870s for the Royal Navy to oppose the perceived growing threat from the Italian Regia Marina in the Mediterranean.The Italian Navy had started constructing a...

.

Steel was also an obvious material for armor. It was tested in the 1860s, but the steel of the time was too brittle
Brittle
A material is brittle if, when subjected to stress, it breaks without significant deformation . Brittle materials absorb relatively little energy prior to fracture, even those of high strength. Breaking is often accompanied by a snapping sound. Brittle materials include most ceramics and glasses ...

 and disintegrated when struck by shells. Steel became practical to use when a way was found to fuse steel onto wrought iron plates, giving a form of compound armor. This compound armor was used by the British in ships built from the late 1870s, first for turret armor (starting with HMS Inflexible) and then for all armor (starting with Colossus
HMS Colossus (1882)
The second HMS Colossus was a Colossus class second-class British battleship, launched in 1882 and commissioned in 1886. She had a displacement of 9,520 tons, and an armament of 4 × 12-inch breechloaders, 5 × 6-inch guns and had a respectable speed of 15.5 knots. She served in the Mediterranean...

 of 1882). The French and German navies adopted the innovation almost immediately, with licenses being given for the use of the 'Wilson System' of producing fused armor.

The first ironclads to have all-steel armor were the Italian Duilio and Dandolo. Though the ships were laid down in 1873 their armor was not purchased from France until 1877. The French navy decided in 1880 to adopt compound armor for its fleet, but found it limited in supply, so from 1884 the French navy was using steel armor. Britain stuck to compound armor until 1889.

The ultimate ironclad armor was case hardened
Case hardening
Case hardening or surface hardening is the process of hardening the surface of a metal, often a low carbon steel, by infusing elements into the material's surface, forming a thin layer of a harder alloy...

 nickel-steel. In 1890, the U.S. Navy tested steel armor hardened by the Harvey process and found it superior to compound armor. For several years 'Harvey steel' was the state of the art, produced in the U.S., France, Germany, Britain, Austria and Italy. In 1894, the German firm Krupp
Krupp
The Krupp family , a prominent 400-year-old German dynasty from Essen, have become famous for their steel production and for their manufacture of ammunition and armaments. The family business, known as Friedrich Krupp AG Hoesch-Krupp, was the largest company in Europe at the beginning of the 20th...

 developed gas cementing
Krupp armour
Krupp armour was a type of steel armour used in the construction of capital ships starting shortly before the end of the 19th century. It was developed by Germany's Krupp Arms Works in 1893 and quickly replaced Harvey armour as the primary method of protecting naval ships.The initial manufacturing...

, which further hardened steel armor. The German Kaiser Friedrich III
Kaiser Friedrich III class battleship
Kaiser Friedrich III class battleships were a class of pre–World War I, pre-dreadnought battleships of the German Kaiserliche Marine. The class was made up of five ships, all of which were named for German emperors...

, laid down in 1895, was the first ship to benefit from the new 'Krupp armor' and the new armor was quickly adopted; the Royal Navy using it from HMS Canopus
HMS Canopus (1898)
HMS Canopus was a pre-dreadnought battleship of the British Royal Navy and the lead ship of the Canopus-class. At the beginning of the First world war she was involved in the search for the German East Asia Squadron of Admiral Graf Spee...

, laid down in 1896. By 1901 almost all new battleships used Krupp armor, though the U.S. continued to use Harvey armor alongside until the end of the decade.

The equivalent strengths of the different armor plates was as follows: 15 in (381 mm) of wrought iron was equivalent to 12 in (305 mm) of either plain steel or compound iron and steel armor, and to 7.75 in (197 mm) of Harvey armor or 5.75 in (146 mm) of Krupp armor.

Ironclad construction also prefigured the later debate in battleship design between tapering and 'all-or-nothing' armour design. Warrior was only semi-armoured, and could have been disabled by hits on the bow and stern. As the thickness of armor grew to protect ships from the increasingly heavy guns, the area of the ship which could be fully protected diminished. Inflexibles armor protection was largely limited to the central citadel amidships, protecting boilers and engines, turrets and magazines, and little else. An ingenious arrangement of cork-filled compartments and watertight bulkheads was intended to keep her stable and afloat in the event of heavy damage to her un-armored sections.

Propulsion: steam and sail



The first ocean-going ironclads carried masts and sails like their wooden predecessors, and these features were only gradually abandoned. Early steam engines were inefficient; the wooden steam fleet of the Royal Navy could only carry "5 to 9 days coal", and the situation was similar with the early ironclads. Warrior also illustrates two design features which aided hybrid propulsion; she had retractable screws to reduce drag while under sail (though in practice the steam engine was run at a low throttle), and a telescopic funnel which could be folded down to the deck level.


Ships designed for coastal warfare, like the floating batteries of the Crimea, or USS Monitor
USS Monitor
USS Monitor was the first ironclad warship commissioned by the United States Navy during the American Civil War. She is most famous for her participation in the Battle of Hampton Roads on March 9, 1862, the first-ever battle fought between two ironclads...

 and her sisters, dispensed with masts from the beginning. The British HMS Devastation
HMS Devastation (1871)
HMS Devastation was the first of two Devastation-class mastless turret ships built for the British Royal Navy. This was the first class of ocean-going capital ship that did not carry sails, and the first whose entire main armament was mounted on top of the hull rather than inside it...

, started in 1869, was the first large, ocean-going ironclad to dispense with masts. Her principal role was for combat in the English Channel and other European waters; and while her coal supplies gave her enough range to cross the Atlantic, she would have had little endurance on the other side of the ocean. The Devastation and the similar ships commissioned by the British and Russian navies in the 1870s were the exception rather than the rule. Most ironclads of the 1870s retained masts, and only the Italian navy, which during that decade was focused on short-range operations in the Adriatic, built consistently mastless ironclads.

During the 1860s, steam engines improved with the adoption of double-expansion steam engines, which used 30–40% less coal than earlier models. The Royal Navy decided to switch to the double-expansion engine in 1871, and by 1875 they were widespread. However, this development alone was not enough to herald the end of the mast. Whether this was due to a conservative desire to retain sails, or was a rational response to the operational and strategic situation, is a matter of debate. A steam-only fleet would require a network of coaling stations worldwide, which would need to be fortified at great expense to stop them falling into enemy hands. Just as significantly, because of unsolved problems with the technology of the boilers which provided steam for the engines, the performance of double-expansion engines was rarely as good in practice as it was in theory.
During the 1870s the distinction grew between 'first-class ironclads' or 'battleships' on the one hand, and 'cruising ironclads' designed for long-range work on the other. The demands on first-class ironclads for very heavy armor and armament meant increasing displacement, which reduced speed under sail; and the fashion for turrets and barbettes made a sailing rig increasingly inconvenient. HMS Inflexible
HMS Inflexible (1876)
HMS Inflexible was a Victorian ironclad battleship carrying her main armament in centrally placed turrets. The ship was constructed in the 1870s for the Royal Navy to oppose the perceived growing threat from the Italian Regia Marina in the Mediterranean.The Italian Navy had started constructing a...

, launched in 1876 but not commissioned until 1881, was the last British battleship to carry masts, and these were widely seen as a mistake. The start of the 1880s saw the end of sailing rig on ironclad battleships.

Sails persisted on 'cruising ironclads' for much longer. During the 1860s, the French navy had produced the Alma and La Galissoniere classes as small, long-range ironclads as overseas cruisers and the British had responded with ships like Swiftsure
HMS Swiftsure (1870)
HMS Swiftsure was the lead ship of the Swiftsure class battleships built in the late Victorian era. Her sister-ship was .-Service history:...

 of 1870. The Russian ship General Admiral, laid down in 1870 and completed in 1875, was a model of a fast, long-range ironclad which was likely to be able to out-run and out-fight ships like Swiftsure. Even the later HMS Shannon
HMS Shannon (1875)
The eighth HMS Shannon was the first British armoured cruiser. She was the last Royal Navy ironclad to be built which had a propeller that could be hoisted out of the water to reduce drag when she was under sail, and the first to have an armoured deck....

, often described as the first British armored cruiser, would have been too slow to outrun General Admiral. While Shannon was the last British ship with a retractable propellor, later armored cruisers of the 1870s retained sailing rig, sacrificing speed under steam in consequence. It took until 1881 for the Royal Navy to lay down a long-range armored warship capable of catching enemy commerce raiders, Warspite
HMS Warspite (1884)
HMS Warspite was an Imperieuse-class first-class armoured cruiser, launched on 29 January 1884 and commissioned in 1886. Warspite was the flagship on the Pacific Station between 1890 and 1893, then a port guard ship at Queenstown until 1896...

, which was completed in 1888. While sailing rigs were obsolescent for all purposes by the end of the 1880s, rigged ships were in service until the early years of the 20th century.

The final evolution of ironclad propulsion was the adoption of the triple-expansion steam engine, a further refinement which was first adopted in HMS Sans Pareil
HMS Sans Pareil (1887)
HMS Sans Pareil was a Victoria Class battleship of the British Royal Navy of the Victorian era, her only sister-ship being .In deciding upon her design configuration the Board of Admiralty took what history shows was a retrograde step by requesting the reversion from barbettes to turrets for her...

, laid down in 1885 and commissioned in 1891. Many ships also used a forced draught to get additional power from their engines, and this system was widely used until the introduction of the steam turbine
Steam turbine
A steam turbine is a mechanical device that extracts thermal energy from pressurized steam, and converts it into rotary motion. Its modern manifestation was invented by Sir Charles Parsons in 1884....

 in the mid-1900s.

Fleets


While ironclads spread rapidly in navies worldwide, there were few pitched naval battles involving ironclads. Most European nations settled differences on land, and the Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 dominated the sea to such an extent that no rival power could effectively challenge Britain. The naval engagements involving ironclads normally involved colonial actions or clashes between second-rate naval powers.

There were many types of ironclads:
  • Seagoing ships intended to "stand in the line of battle"; the precursors of the battleship
    Battleship
    A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...

    .
  • Coastal service and riverine vessels, including 'floating batteries'
    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 during the Great Siege of Gibraltar....

     and 'monitors'
    Monitor (warship)
    A monitor was a class of relatively small warship which was neither fast nor strongly armoured but carried disproportionately large guns. They were used by some navies from the 1860s until the end of World War II, and saw their final use by the United States Navy during the Vietnam War.The monitors...

  • Vessels intended for commerce raiding
    Commerce raiding
    Commerce raiding or guerre de course is a form of naval warfare used to destroy or disrupt the logistics of an enemy on the open sea by attacking its merchant shipping, rather than engaging the combatants themselves or enforcing a blockade against them.Commerce raiding was heavily criticised by...

     or protection of commerce, called 'armoured cruisers'

Navies


The United Kingdom possessed the largest navy in the world for the whole of the ironclad period. The Royal Navy
Royal Navy
The Royal Navy is the naval warfare service branch of the British Armed Forces. Founded in the 16th century, it is the oldest service branch and is known as the Senior Service...

 was the second to adopt ironclad warships, and it applied them worldwide in their whole range of roles. In the age of sail, the British strategy for war depended on the Royal Navy mounting a blockade of the ports of the enemy. Because of the limited endurance of steamships, this was no longer possible, so the British planned to engage an enemy fleet in harbor as soon as war broke out. To this end, the Royal Navy developed a series of 'coast-assault battleships', starting with the Devastation class. These 'breastwork monitors
Monitor (warship)
A monitor was a class of relatively small warship which was neither fast nor strongly armoured but carried disproportionately large guns. They were used by some navies from the 1860s until the end of World War II, and saw their final use by the United States Navy during the Vietnam War.The monitors...

' were markedly different from the other high-seas ironclads of the period and were an important precursor of the modern battleship. Through the 1860s and 1870s the Royal Navy was superior to its potential rivals, but in the early 1880s widespread concern about the threat from France and Germany culminated in the Naval Defence Act which promulgated the idea of a 'two-power standard', that Britain should possess as many ships as the next two navies combined. This standard provoked aggressive shipbuilding in the 1880s and 1890s.

British ships did not participate in any major wars in the ironclad period. The Royal Navy's ironclads only saw action as part of colonial battles or one-sided engagements like the bombardment of Alexandria in 1882. Defending British interests against Ahmed 'Urabi's Egyptian revolt
Urabi Revolt
The Urabi Revolt or Orabi Revolt , also known as the Orabi Revolution, was an uprising in Egypt in 1879-82 against the Khedive and European influence in the country...

, a British fleet opened fire on the fortifications around the port of Alexandria. A mixture of centre-battery and turret ships bombarded Egyptian positions for most of a day, forcing the Egyptians
Egyptians
Egyptians are nation an ethnic group made up of Mediterranean North Africans, the indigenous people of Egypt.Egyptian identity is closely tied to geography. The population of Egypt is concentrated in the lower Nile Valley, the small strip of cultivable land stretching from the First Cataract to...

 to retreat; return fire from Egyptian guns was heavy at first, but inflicted little damage, killing only five British sailors.

The French navy built the first ironclad to try to gain a strategic advantage over the British, but were consistently out-built by the British. Despite taking the lead with a number of innovations like breech-loading weapon
Breech-loading weapon
A breech-loading weapon is a firearm in which the cartridge or shell is inserted or loaded into a chamber integral to the rear portion of a barrel....

s and steel construction, the French navy could never match the size of the Royal Navy. In the 1870s, the construction of ironclads ceased for a while in France as the Jeune Ecole
Jeune Ecole
The Jeune École was a strategic naval concept developed during the 19th century. It advocated the use of small, powerfully equipped units to combat a larger battleship fleet, and commerce raiders capable of ending the trade of the rival nation...

 school of naval thought took prominence, suggesting that torpedo boat
Torpedo boat
A torpedo boat is a relatively small and fast naval vessel designed to carry torpedoes into battle. The first designs rammed enemy ships with explosive spar torpedoes, and later designs launched self-propelled Whitehead torpedoes. They were created to counter battleships and other large, slow and...

s and unarmored cruisers would be the future of warships. Like the British, the French navy saw little action with its ironclads; the French blockade of Germany in the Franco-Prussian War
Franco-Prussian War
The Franco-Prussian War or Franco-German War, often referred to in France as the 1870 War was a conflict between the Second French Empire and the Kingdom of Prussia. Prussia was aided by the North German Confederation, of which it was a member, and the South German states of Baden, Württemberg and...

 was ineffective, as the war was settled entirely on land.

Russia built a number of ironclads, generally copies of British or French designs. Nonetheless, there were real innovations from Russia; the first true type of ironclad armored cruiser
Armored cruiser
The armored cruiser was a type of warship of the late 19th and early 20th centuries. Like other types of cruiser, the armored cruiser was a long-range, independent warship, capable of defeating any ship apart from a battleship, and fast enough to outrun any battleships it encountered.The first...

, the General Admiral of the 1870s, and a set of remarkably badly designed circular battleships
Russian battleship Novgorod
The Novgorod was an Imperial Russian warship. It was one of the most unusual warships ever constructed, and still survives in popular naval myth, often described as the "ugliest warship ever built". Together with her near-sister ship Rear Admiral Popov, they were affectionately called "popovkas",...

 referred to as 'popoffkas'. The Russian Navy pioneered the wide-scale use of torpedo boats during the Russo-Turkish War of 1877–1878, mainly out of necessity because of the superior numbers and quality of ironclads used by the Turkish navy. Russia expanded her navy in the 1880s and 1890s with modern armored cruisers and battleships, but the ships were manned by inexperienced crews and politically appointed leadership, which enhanced their defeat in the Battle of Tsushima
Battle of Tsushima
The Battle of Tsushima , commonly known as the “Sea of Japan Naval Battle” in Japan and the “Battle of Tsushima Strait”, was the major naval battle fought between Russia and Japan during the Russo-Japanese War...

 on 27 May 1905.


The U.S. Navy ended the Civil War with about fifty monitor
Monitor (warship)
A monitor was a class of relatively small warship which was neither fast nor strongly armoured but carried disproportionately large guns. They were used by some navies from the 1860s until the end of World War II, and saw their final use by the United States Navy during the Vietnam War.The monitors...

-type coastal ironclads; by the 1870s most of these were laid up in reserve, leaving the USA virtually without an ironclad fleet. Another five large monitors were ordered in the 1870s. The limitations of the monitor type effectively prevented the USA from projecting power overseas, and until the 1890s the USA would have come off badly in a conflict with even Spain or the Latin American powers. The 1890s saw the beginning of what became the Great White Fleet
Great White Fleet
The Great White Fleet was the popular nickname for the United States Navy battle fleet that completed a circumnavigation of the globe from 16 December 1907 to 22 February 1909 by order of U.S. President Theodore Roosevelt. It consisted of 16 battleships divided into two squadrons, along with...

, and it was the modern pre-Dreadnoughts and armored cruisers built in the 1890s which defeated the Spanish fleet in the Spanish-American War
Spanish-American War
The Spanish–American War was a conflict in 1898 between Spain and the United States, effectively the result of American intervention in the ongoing Cuban War of Independence...

 of 1898. This started a new era of naval warfare.


Ironclads were widely used in South America. Both sides used ironclads in the Chincha Islands War
Chincha Islands War
The Chincha Islands War was a series of coastal and naval battles between Spain and its former colonies of Peru and Chile from 1864 to 1866, that began with Spain's seizure of the guano-rich Chincha Islands, part of a series of attempts by Isabel II of Spain to reassert her country's lost...

 between Spain and the combined forces of Peru
Peru
Peru , officially the Republic of Peru , is a country in western South America. It is bordered on the north by Ecuador and Colombia, on the east by Brazil, on the southeast by Bolivia, on the south by Chile, and on the west by the Pacific Ocean....

 and Chile
Chile
Chile ,officially the Republic of Chile , is a country in South America occupying a long, narrow coastal strip between the Andes mountains to the east and the Pacific Ocean to the west. It borders Peru to the north, Bolivia to the northeast, Argentina to the east, and the Drake Passage in the far...

 in the early 1860s. The powerful Spanish Numancia participated in the Battle of Callao
Battle of Callao
The Battle of Callao occurred on May 2, 1866 between a Spanish fleet under the command of Admiral Casto Méndez Núñez and the fortified battery emplacements of the Peruvian port city of Callao during the Chincha Islands War...

 but was unable to inflict significant damage to the Callao defences. Besides, Peru was able to deploy two locally built ironclads based on American Civil War designs, the Loa (a wooden ship converted into a casemate ironclad) and the Victoria (an small monitor armed with a single 68 pdr gun), as well as two British-built ironclads; Independencia, a centre-battery ship, and the turret ship Huáscar
Huáscar (ship)
Huáscar is a 19th century small armoured turret ship of a type similar to a monitor. She was built in Britain for Peru and played a significant role in the battle of Pacocha and the War of the Pacific against Chile before being captured and commissioned with the Chilean Navy. Today she is one of...

. Numancia was the first ironclad to circumnavigate the world, arriving in Cádiz
Cádiz
Cadiz is a city and port in southwestern Spain. It is the capital of the homonymous province, one of eight which make up the autonomous community of Andalusia....

 on 20 September 1867, and earning the motto: "Enloricata navis que primo terram circuivit"). In the War of the Pacific
War of the Pacific
The War of the Pacific took place in western South America from 1879 through 1883. Chile fought against Bolivia and Peru. Despite cooperation among the three nations in the war against Spain, disputes soon arose over the mineral-rich Peruvian provinces of Tarapaca, Tacna, and Arica, and the...

 in 1879, both Peru and Chile had ironclad warships, including some of those used a few years previously against Spain. While the Independencia ran aground early on, the Peruvian ironclad Huáscar
Huáscar (ship)
Huáscar is a 19th century small armoured turret ship of a type similar to a monitor. She was built in Britain for Peru and played a significant role in the battle of Pacocha and the War of the Pacific against Chile before being captured and commissioned with the Chilean Navy. Today she is one of...

 made a great impact against Chilean shipping, delaying Chilean ground invasion by six months. She was eventually caught by two more modern Chilean centre-battery ironclads, the Blanco Encalada and the Almirante Cochrane at the Battle of Angamos Point
Battle of Angamos
The Battle of Angamos was fought on October 8, 1879, during the naval stage of the War of the Pacific . The Chilean Navy, commanded by Captain Galvarino Riveros and Captain Juan Jose Latorre surrounded and captured the ironclad Huáscar, commanded by Rear Admiral Miguel Grau Seminario, who died in...

.

Ironclads were also used from the inception of the Imperial Japanese Navy
Imperial Japanese Navy
The Imperial Japanese Navy was the navy of the Empire of Japan from 1869 until 1947, when it was dissolved following Japan's constitutional renunciation of the use of force as a means of settling international disputes...

. The Kōtetsu
Japanese battleship Kotetsu
, later renamed was the first ironclad warship of the Imperial Japanese Navy. Built in France in 1864 for the Confederate States Navy, and acquired from the United States in February 1869, she was an ironclad ram warship...

 (Japanese: 甲鉄, literally "Ironclad", later renamed Azuma 東, "East") had a decisive role in the Naval Battle of Hakodate Bay in May 1869, which marked the end of the Boshin War
Boshin War
The was a civil war in Japan, fought from 1868 to 1869 between forces of the ruling Tokugawa shogunate and those seeking to return political power to the imperial court....

, and the complete establishment of the Meiji Restoration
Meiji Restoration
The , also known as the Meiji Ishin, Revolution, Reform or Renewal, was a chain of events that restored imperial rule to Japan in 1868...

. The IJN continued to develop its strength and commissioned a number of warships from British and European shipyards, first ironclads and later armored cruiser
Armored cruiser
The armored cruiser was a type of warship of the late 19th and early 20th centuries. Like other types of cruiser, the armored cruiser was a long-range, independent warship, capable of defeating any ship apart from a battleship, and fast enough to outrun any battleships it encountered.The first...

s. These ships engaged the Chinese Beiyang fleet
Beiyang Fleet
The Beiyang Fleet was one of the four modernised Chinese navies in the late Qing Dynasty. Among the four, the Beiyang Fleet was particularly sponsored by Li Hongzhang, one of the most trusted vassals of Empress Dowager Cixi and the principal patron of the "self-strengthening movement" in northern...

 which was superior on paper at least at the Battle of the Yalu River
Battle of Yalu River (1894)
The Battle of the Yalu River , also called simply 'The Battle of Yalu' took place on September 17, 1894. It involved the Japanese and the Chinese navies, and was the largest naval engagement of the First Sino-Japanese War...

. Thanks to superior short-range firepower, the Japanese fleet came off better, sinking or severely damaging eight ships and receiving serious damage to only four. The naval war was concluded the next year at the Battle of Weihaiwei
Battle of Weihaiwei
The Battle of Weihaiwei was a 23 day siege with a major land and naval component during the First Sino-Japanese War. It took place between 20 January and 12 February 1895 in Weihai, Shandong Province, China) between the forces of Meiji Japan and Qing China...

, where the strongest remaining Chinese ships were surrendered to the Japanese.

End of the ironclad



There is no clearly defined end to the ironclad, besides the transition from wood hulls to all metal. Ironclads continued to be used in World War I. Towards the end of the 19th century, the descriptions 'battleship
Battleship
A battleship is a large armored warship with a main battery consisting of heavy caliber guns. Battleships were larger, better armed and armored than cruisers and destroyers. As the largest armed ships in a fleet, battleships were used to attain command of the sea and represented the apex of a...

' and 'armored cruiser
Armored cruiser
The armored cruiser was a type of warship of the late 19th and early 20th centuries. Like other types of cruiser, the armored cruiser was a long-range, independent warship, capable of defeating any ship apart from a battleship, and fast enough to outrun any battleships it encountered.The first...

' came to replace the term 'ironclad'.

The proliferation of ironclad battleship designs came to an end in the 1890s as navies reached a consensus on the design of battleships, producing the type known as the pre-Dreadnought
Pre-dreadnought
Pre-dreadnought battleship is the general term for all of the types of sea-going battleships built between the mid-1890s and 1905. Pre-dreadnoughts replaced the ironclad warships of the 1870s and 1880s...

. These ships are sometimes covered in treatments of the ironclad warship. The next evolution of battleship design, the dreadnought
Dreadnought
The dreadnought was the predominant type of 20th-century battleship. The first of the kind, the Royal Navy's had such an impact when launched in 1906 that similar battleships built after her were referred to as "dreadnoughts", and earlier battleships became known as pre-dreadnoughts...

, is never referred to as an 'ironclad'.

Most of the ironclads of the 1870s and 1880s served into the first decade of the 20th century. A handful, for instance US navy monitors laid down in the 1870s, saw active service in World War I. Pre-Dreadnought battleships and cruisers of the 1890s saw widespread action in World War I and in some cases through to World War II.

Legacy



The example of the ironclads had some bearing on the history of the tank
History of the tank
The history of the tank began in World War I, when armoured all-terrain fighting vehicles were first deployed as a response to the problems of trench warfare, ushering in a new era of mechanized warfare. Though initially crude and unreliable, tanks eventually became a mainstay of ground armies...

, as ironclad warships became an inspiration for ideas of landships and other armored vehicles. H. G. Wells
H. G. Wells
Herbert George Wells was an English author, now best known for his work in the science fiction genre. He was also a prolific writer in many other genres, including contemporary novels, history, politics and social commentary, even writing text books and rules for war games...

, in his short story The Land Ironclads
The Land Ironclads
Written by H. G. Wells, "The Land Ironclads" is a short story that originally appeared in the December 1903 issue of the Strand Magazine and set in a war similar to the First World War...

, published in The Strand Magazine in December 1903, described the use of large, armoured cross-country vehicles, armed with cannon and machine guns, and equipped with pedrail wheels

Today


A number of ironclads have been preserved or reconstructed as museum ships.
  • Part of the USS Monitor
    USS Monitor
    USS Monitor was the first ironclad warship commissioned by the United States Navy during the American Civil War. She is most famous for her participation in the Battle of Hampton Roads on March 9, 1862, the first-ever battle fought between two ironclads...

     have been recovered and are displayed at the Mariners' Museum
    Mariners' Museum
    The Mariners' Museum is located in Newport News, Virginia. It is one of the largest maritime museums in the world as well as being the largest in North America.- History :The museum was founded in 1932 by Archer Milton Huntington, son of Collis P...

     in Newport News, Virginia
    Newport News, Virginia
    Newport News is an independent city located in the Hampton Roads metropolitan area of Virginia. It is at the southeastern end of the Virginia Peninsula, on the north shore of the James River extending southeast from Skiffe's Creek along many miles of waterfront to the river's mouth at Newport News...

  • HMS Warrior
    HMS Warrior (1860)
    HMS Warrior was the first iron-hulled, armour-plated warship, built for the Royal Navy in response to the first ironclad warship, the French Gloire, launched a year earlier....

     is today a fully restored museum ship in Portsmouth
    Portsmouth
    Portsmouth is the second largest city in the ceremonial county of Hampshire on the south coast of England. Portsmouth is notable for being the United Kingdom's only island city; it is located mainly on Portsea Island...

    , England.
  • Huáscar
    Huáscar (ship)
    Huáscar is a 19th century small armoured turret ship of a type similar to a monitor. She was built in Britain for Peru and played a significant role in the battle of Pacocha and the War of the Pacific against Chile before being captured and commissioned with the Chilean Navy. Today she is one of...

     is berthed at the port of Talcahuano, Chile, on display for visitors.
  • The City class ironclad
    City class ironclad
    The Pook Turtles, or City class gunboats to use their semi-official name, were war vessels intended for service on the Mississippi River during the American Civil War. They were also sometimes referred to as "Eads gunboats." The labels are applied to seven vessels of uniform design built from...

      is currently on display in Vicksburg
    Vicksburg, Mississippi
    Vicksburg is a city in Warren County, Mississippi, United States. It is the only city in Warren County. It is located northwest of New Orleans on the Mississippi and Yazoo rivers, and due west of Jackson, the state capital. In 1900, 14,834 people lived in Vicksburg; in 1910, 20,814; in 1920,...

    , Mississippi
    Mississippi
    Mississippi is a U.S. state located in the Southern United States. Jackson is the state capital and largest city. The name of the state derives from the Mississippi River, which flows along its western boundary, whose name comes from the Ojibwe word misi-ziibi...

    .
  • Northrop Grumman
    Northrop Grumman
    Northrop Grumman Corporation is an American global aerospace and defense technology company formed by the 1994 purchase of Grumman by Northrop. The company was the fourth-largest defense contractor in the world as of 2010, and the largest builder of naval vessels. Northrop Grumman employs over...

     in Newport News constructed a full-scale replica of . The replica was laid down in February, 2005 and completed just two months later.
  • The Dutch Ramtorenschip (Coastal ram) Zr. Ms. Buffel
    HNLMS Buffel
    HNLMS Buffel is a 19th century iron-clad ram ship, now one of the main attractions of the Maritime Museum Rotterdam, also known as the Prince Hendrik Museum, named after its founder, Prince Henry "the Navigator", who had a naval career and established the basis of the museum back in 1874.- Build...

     is currently under display in the Maritime Museum Rotterdam
    Maritime Museum Rotterdam
    The Maritime Museum Rotterdam is a maritime museum in Rotterdam, the Netherlands. Dedicated to naval history, it was founded in 1873 by Prince Henry of the Netherlands. One of the major attractions is the 19th-century ironclad ram ship HNLMS Buffel, which is moored outside of the museum.-External...

    .
  • The Dutch Ramtorenschip (Coastal ram) Zr. Ms. Schorpioen
    HNLMS Schorpioen
    HNLMS Schorpioen is a sister ship of HNLMS Buffel. Built in the same year, 1868 in France, they were the core of the then renewed Royal Netherlands Navy, replacing the outdated wooden ships that combined sailing and steam propulsion and carried so called smooth-bore guns. These new ships were...

     is a museum ship at Den Helder.
  • The complete, recovered wooden hull of the CSS Neuse
    CSS Neuse
    The CSS Neuse was an ironclad warship of the Confederate States Navy during the American Civil War. The remains of the ship can now be seen at an exhibit in Kinston, North Carolina as the CSS Neuse State Historic Site and Governor Caswell Memorial...

    , a casemate ram ironclad, is on view in Kinston, North Carolina
    Kinston, North Carolina
    Kinston is a city in Lenoir County, North Carolina, United States. The population was 23,688 at the 2000 census. The population was estimated at 22,360 in 2008. It has been the county seat of Lenoir County since its formation in 1791 . Kinston is located in North Carolina's Inner Banks...

    , and, in another part of town on the Neuse River
    Neuse River
    The Neuse River is a river rising in the Piedmont of North Carolina and emptying into Pamlico Sound below New Bern. Its total length is approximately , making it the longest river entirely contained in North Carolina. The Trent River joins it at New Bern. Its drainage basin, measuring in area,...

    , the recreated ship, named CSS Neuse II, is nearly built and can be visited.
  • The hull of the casemate ironclad CSS Jackson
    CSS Jackson
    CSS Jackson was a gunboat of the Confederate Navy during the American Civil War.Built at Cincinnati, Ohio, in 1849 as Yankee, the fast side-wheel river tug was purchased at New Orleans on 9 May 1861 by Capt. L. Rousseau, CSN, then strengthened and fitted for service in the Confederate Navy, and...

     can be seen in the National Civil War Naval Museum at Port Columbus, Georgia.

External links