Created | Updated Mar 5, 2014
During the reign of Queen Victoria, 'Britannia rules the waves' was more than just a song lyric; it was an unquestioned fact. Britain's naval policy was simple - keep the Royal Navy superior, both technologically and numerically, to any other two navies in the world combined. Other nations tried to compete with Britain's superiority, and France posed a serious threat in the 1850s and 1860s.
In 1860, HMS Warrior, the world's first iron warship, was launched in London. She completely revolutionised the way warships were built and rendered existing warships obsolete.
Development of the Ironclad
At the end of the Napoleonic War, in 1815, the most powerful ships in the world were wooden, three-decker, 120-gun, first rate ships of the line.
Iron had already been used in British ship building, with iron barges in use before the end of the 18th Century. In 1821, Charles Manbury built the iron paddle steamer Aaron Manby and in 1843 Isambard Kingdom Brunel built the Great Britain, the first large iron ship to cross the Atlantic. The first armed iron ship was the Nemesis, a paddle-gunboat owned by the Honourable East India Company, built in 1839 and used in the Opium War of 1841. The British Royal Navy also considered the use of iron. Between 1843 and 1846, six frigates were built. However, it was discovered that their shell plating became fragmented when fractured by shot. They were subsequently converted into troopships. Later, the British Chief Naval Engineer, Thomas Lloyd, solved the problem with four-inch armour plating.
A principal problem of iron ships was the effect on the ship's compass - the Astronomer Royal, Professor Sir George Airy, solved this particular problem. In 1838, using the iron steamer Rainbow for his experiments, Airy found he could neutralise a ship's magnetism by placing magnets and pieces of demagnetised iron near the compass.
During the Crimean War (1854 - 1856), France, then Britain, used iron to build floating batteries. These were floating, although unseaworthy, vessels intended to carry heavy guns and destroy Russian defences1.
Around 1837, Brunel built the Great Western, a transatlantic paddle steamer. In 1843, the iron-hulled Great Britain was built. Large paddle-frigates were built, such as HMS Terrible, launched in 1845, and which fought during the Crimean War. Although larger than the 74-gun ships at the Battle of Trafalgar, HMS Terrible carried just 19 guns. The paddle wheel, which had to be on each side of the hull, both reduced the number of guns that could be mounted broadside and was also a vulnerable target. If the paddle wheel was destroyed, the ship would be helpless and unable to move. Only with the invention of the screw propeller were steam-powered warships practical. Cannon would not be obstructed, and the under water propeller was out of harm's way.
The screw propeller was first used to good effect on a military vessel in 1852, when the French, wooden, two-decker, 90-gun, Le Napoleon, the first steam-powered battleship, started a brief arms race. She was built to be fast but her engines were unreliable. Britain's first steam-powered warship, the 91-gun HMS Agamemnon, was launched soon after in reply. Britain still had more experience in warship design, and she was superior in most respects, including engines, design and weaponry. Over 100 two- or three-decked wooden steam battleships were built, or converted, in Britain and France, in the next ten years (66 by Britain alone), although the introduction of iron soon rendered them obsolete.
While France built more and more Napoleon class vessels, Britain kept re-designing and improving her ships. This resulted in the building of the 101-gun ships, HMS Duncan and her sister ship HMS Gibraltar, in 1858, and the 120-gun HMS Victoria, Britain’s last, and the largest wooden warship ever, launched in 1864.
With the advances in iron shipbuilding, and the introduction of practical steam-propelled warships, the development of iron warships became inevitable.
The French took the first step towards developing ironclads. In 1857, Stanlais Dupey de Lome started work on a new warship, La Gloire. She was to have a wooden hull, armoured with iron clad plating above the waterline. Not being built of iron, merely re-enforced with it, she was an ‘ironclad’ warship, but not an iron ship2. La Gloire was to have a radical effect on the way warships were designed.
Britain's navy, her first line of defence, seemed to be challenged, and perhaps out of date. This caused the invasion scare of 1858 - 1859, which resulted in the building of several forts around the country. People were afraid that the Emperor, Napoleon III was seriously planning to invade Britain. He did not and France was later overwhelmingly defeated in the Franco-Prussian war of 1870 - 1871 by a smaller and less experienced German army. At the time, though, France seemed a very real source of danger. Despite being Britain's ally during the Crimean War, she now seemed distant and had become allied with Russia, whom Britain had fought against in Crimea. It was feared that France and Russia might jointly attack Britain. Prime Minister, Lord Palmerston wrote to the Duke of Somerset in September 1859:
Now we must remember that we might have to encounter not only the French navy, but the combined navies of France and Russia.
The British Royal Navy soon built a response to La Gloire - the HMS Warrior - the world's first true iron warship. However, La Gloire was not as serious a threat as the Royal Navy feared.
La Gloire was the first of six French ironclads of the same type. Only one, the Couronne, was a true iron ship, built after HMS Warrior. It had been intended to build La Gloire as an iron ship, but at that time, France did not have the technology or experience that Britain had with iron.
La Gloire was essentially a wooden battleship with iron plating, hence, despite being a great leap forward, she was also a dead end in ship design. She was confined by the limits of her wooden hull, and carried a total of 34 guns. These were inferior to the 68pdr (pounder) guns that Warrior carried, and were also crowded on the gun deck. With the gun embrasures so close together, the protection the iron armour offered was weakened.
Furthermore, the iron was of poor quality and she was not a very seaworthy vessel. In heavy weather, La Gloire was practically disarmed as her gun ports were too close to the waterline. If they were opened during rough seas, there was a strong possibility that she would flood.
La Gloire was not designed as an ocean-going ship, and spent her time in the Mediterranean and the English Channel. Designed primarily to rely on steam, her range was quite short, confined by the limited amount of coal she could carry. She was also only equipped with a light barque rig. La Gloire was not designed to sail alone, but to be the strongest part of a fleet engaged in traditional broadside battles, and so conceptually, was not that different from a wooden warship.
Curiously, France did not spend as much time building her as would be expected. All wooden ships must be built over at least three years; otherwise they suffer from dry rot. However, La Gloire was launched without being given time to air3.
So, despite being a very advanced warship, she did not pose the threat feared by the Royal Navy. Not only was HMS Warrior superior to her, but HMS Duncan and her sister ships, when later converted into ironclads, proved superior too, especially where seaworthiness was concerned.
The simplest solution to the problem posed by La Gloire was to coat existing ships in iron, but the Admiralty did not take this approach. Later, however, they did convert several 'wooden walls', as the Navy's wooden fleet was affectionately known. Admiral Sir Baldwin Walker had investigated the possibilities of iron in 1856, even before La Gloire was started. Tests showed that four-inch armour plating would resist the shots of the 68pdr-gun, even at almost point blank range. Following the tests, Walker wrote:
I have frequently stated that it is not in the interest of Great Britain, possessing as she does so large a navy, to adopt any important change in the construction of ships of war, which might have the effect of rendering necessary the introduction of a new class of very costly vessels, until such a course is forced onto us.
Further armour trials in 1858 showed that no weapon could penetrate four-and-a-half inches of iron plating, and not until 1865 was a gun designed that could. The trials also showed that one shot of Britain's 68pdr gun had the same effect as five 32pdr shots hitting close together. The 68pdr gun had been introduced in the Crimean War and was the most effective gun of the day.
Isaac Watts, a ship designer who specialised in long frigates, such as HMS Mersey, was called in to design HMS Warrior. She was to have the four-and-a-half inch armour, in a reinforced box, in the centre of the ship - a design known as the citadel. The bow and stern were not reinforced, but it was thought unlikely that shots to these sections would seriously affect the Warrior. The worst that could happen would be a shot to the rudder, which could disable her steering.
Warrior was designed to be a fast ship. At a time when most warships had a top speed of 10 - 13 knots, Warrior could reach 14 - 17 knots, mainly because she carried the largest engines yet built. Her fine hull enabled her to travel faster and further than most other ships; she was very economical and had a long range.
Warrior was not considered a ship of the line, but a frigate. Most ships of the line were intended to be part of a fleet, but frigates acted independently. Ships were generally designated by the number of guns they carried. Warrior carried just 42 guns, but they were the heaviest available, and she had a larger range and heavier guns than any other warship. She carried 26 68pdr guns, ten 110pdr guns, four 40pdr guns and two 20pdr guns. Her impenetrable armour, phenomenal speed and heavy guns meant that Warrior was superior to any other warship afloat.
However, HMS Warrior had some drawbacks. The first was her size. When she was built, Warrior was the longest warship afloat, and only one other ship in the world was longer; Brunel's Great Eastern. Due to her size, only three docks in the world were able to receive her - Portsmouth, Liverpool and Southampton - all in England. This restricted her to the waters around Great Britain, particularly the English Channel, although she did sail to Gibraltar during the American Civil War and to Bermuda, in 18684. This restriction did not pose a serious problem though, because she had been designed as a response to the French navy, which would sail across the English Channel to invade England5.
The trend to build long, single-decked frigates had been started by the American navy, with their 275 foot long Merrimac class frigates. The American navy had no true first-rate ships at this time. Britain had built two long frigates in 1858 - HMS Mersey and HMS Orlando - the longest, largest and most powerful single-decked wooden fighting ships. Although only 335 feet long, they suffered from the strain of their length, proving too weak to face a ship of the line in close quarters. The Merrimac class also suffered these faults during the American Civil War.
Poor manoeuvrability was another problem faced by Warrior; her turning circle was far too large, making her hard to control. This, therefore, made her entirely unsuitable for fleet manoeuvres. She was even involved in a collision with HMS Royal Oak in August 1868, near the Isles of Scilly, when she was part of the Channel Fleet. Her manoeuvrability problems were partly due to the fact that she was both a steam and sail ship. All steam ships, in a fight, would need a high centre of gravity to prevent the gunfire forcing a roll. Conversely, a sailing ship, in strong winds, needed the stability given by a low centre of gravity. HMS Warrior was a compromise, with her centre of gravity in the middle, and consequently, problems were inevitable.
Despite being a revolutionary ship, some things about Warrior were old-fashioned, such as the knee bow and figurehead. The raised front of a ship was necessary on a wooden vessel, but on iron ships it was not only unnecessary, but increased the weight needlessly. HMS Warrior also had a figurehead on the end of her bow, and along with her sister ship, HMS Black Prince and the HMS Rodney of 1888, was one of the last of the British front-rank ships to carry a figurehead.
HMS Warrior in War
HMS Warrior was designed as a deterrent to prevent Napoleon III from contemplating invading Britain. Napoleon III did not invade, hence Warrior was never involved in action. During the American Civil War she was stationed in British ports, such as Southampton and Gibraltar, where ships from both the Confederacy and Union were in dock at the same time, in order to discourage them from taking the war into British territory.
HMS Warrior's armour would probably have been almost invulnerable in action. No gun at that time, on any vessel, was able to penetrate it at over 400 yards, and Warrior had the speed to escape from any ship approaching too closely. Judging from the Merrimac - Monitor battle in 1862, Warrior’s armour would have been successful. In that battle, the Confederate ironclad Merrimac fought the Union ironclad Monitor non-stop for a day, with neither of them suffering any substantial damage.
HMS Warrior’s main armament was the 68pdr guns first used during the Crimean War. These were very effective, but were smooth bored muzzle-loading guns, which made loading more difficult than with breach-loading weapons, and the lack of rifling affected accuracy. Warrior was also armed with 110pdr 'Armstrong' guns. These were breech loading rifled guns, but it was later discovered that these weapons were inferior to the 68pdr gun. They were inaccurate - the very thing rifling was designed to prevent - and the breech mechanism was flawed. They were replaced in 1864.
Ramming was something which Warrior had been considered for. Although not perfectly equipped, with her type of bow, it could have been an effective weapon. The idea that iron ships could cut through the old-fashioned wooden ones was popular in both Britain and France. It worked effectively in the American Civil War, for instance, when the Merrimac6 rammed and sank the USS Cumberland. Ramming was also used at the Battle of Lissa, in July 1866, when the Austrian Admiral Tegetthoff managed to ram and sink the Italian ironclad Re D'Italia.
Perhaps Warrior would not have been manoeuvrable enough to successfully ram another ship, and her figurehead would probably have suffered most7. There was no sea war for the Royal Navy to try this tactic out on, but both HMS Vanguard and HMS Victoria were sunk by accidental collisions with a ram.
Ironclads after Warrior
In Britain, only two Warrior class vessels were built; HMS Warrior and HMS Black Prince. The government thought they were too expensive, and the navy was ordered to construct four smaller iron warships; HMS Defence, HMS Resistance, HMS Hector and HMS Valiant. These were started in 1859, and finished in 1861. They were smaller than HMS Warrior, did not have her speed or carry her superior firepower, and were not very sea-worthy. Their only advantage was in manoeuvrability, and the absence of Warrior’s archaic bow. HMS Resistance was the first British ship to be equipped with a ram. Warrior had a strong bow and could have rammed but her knee bow would not have been as effective.
The first two of the smaller ships cost £237,291, and the second two also cost £237,291. Compared to HMS Warrior's cost of £357,291, they only offered about a quarter of the military value for two-thirds of Warrior’s price. Indeed, many converted two-deckers proved superior, as they were able to be more heavily armed, and were also faster. After being forced into building them, Admiral Walker, who commissioned the building of Warrior, resigned in February 1861.
In 1863, HMS Achilles was built, and after she was commissioned in 1865, was considered the superior warship of the world. She was a half-sister of Warrior, and had the same speed. She spread the most canvas of any British warship and all Warrior’s faults had been corrected in her design, including more protection for the stern and bow. She remained in service until the beginning of the 20th Century.
Ironclads outside Britain
Many of Britain's wooden wall ships were converted into ironclads. After 1861, the French challenge died out as Napoleon III realised that France's navy was still inferior to Britain's. By 1865, the naval arms race was over Napoleon III tried to re-model his army; this was to little avail as he subsequently lost the Franco-Prussian war of 1870 - 1871. No French ships built before 1870 were any match for HMS Warrior, and no other navy in the world rivalled Britain's position as master of the seas.
The only French ships of note, after the 12 Gloire class vessels, were the Solferino class ships; the Solferino and the Magenta. They were 50-gun, two-deckers and the only true ironclad battleships. They also re-introduced the ram into naval tactics. These were the French response to Warrior and quite good sea boats. They were short and two-decked, instead of one-decked like Warrior, because it was impossible for France to build a larger wooden ship, and France did not have Britain's iron technology. In reply, Britain built the 50-gun Minotaur class, single-decked, ironclads, that were launched in 1863.
The British Minotaur class ships were: HMS Minotaur, HMS Agincourt, and HMS Northumberland, which was the last frigate-hulled iron warship. They were larger than Warrior and Achilles, but also slower under sail, slower even than the smaller iron warships.
1866 saw the launch of the Bellerophon. She was closer in design to a ship of the line, and the first British iron warship not to be frigate shaped. She was smaller and more maneuverable, with thicker armour, but less speed and endurance than Warrior.
In 1869, HMS Monarch was launched; the world's first ocean-going turret ship. Turret ships had been used before, most noticeably in the American Civil War, with ships such as the USS Monitor, but these were mainly used in coastal waters and were not true ocean-going vessels.
The turret ship HMS Captain, was commissioned in 1870, to design specifications suggested by the media and public opinion, although the naval experts of the day claimed she would be unstable. They were proved right when she sank only a few months later. The Captain disaster was due to the Navy's pride in its mast-manship; the handling of the ship's masts and yards. This had grown into a highly competitive drill, and HMS Captain had been designed to have masts perfect for this drill, though useless and dangerous in real sailing conditions. She sank in December 1870, near Cape Finisterre, killing 472 men - more than the number who died at the Battle of Trafalgar. The ship's designer, Cowper Coles, who had publicly campaigned to force the Navy to build her, also died in the disaster.
HMS Devastation, in 1873, was the first mastless capital ship, stable in even the heaviest seas. She was the ancestor of the 20th Century battleship and carried four guns.
HMS Warrior was a revolution in ship design. Although considered second-best to HMS Achilles, after only five years of her career, she was still an exceptional ship, which changed the way future ships were conceived, designed, and built.
HMS Warrior is now one of the only surviving iron warships in the world, and is on display in Portsmouth.