HMS Magdala (1870)
Encyclopedia

HMS Magdala was a breastwork monitor
Breastwork monitor
A breastwork monitor was one of a number of ships designed by Sir Edward Reed, the Chief Constructor of the Royal Navy between 1863 and 1870....

 of 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...

, built specifically to serve as a coastal defence ship
Coastal defence ship
Coastal defence ships were warships built for the purpose of coastal defence, mostly during the period from 1860 to 1920. They were small, often cruiser-sized warships that sacrificed speed and range for armour and armament...

 for the harbour of Bombay (now Mumbai
Mumbai
Mumbai , formerly known as Bombay in English, is the capital of the Indian state of Maharashtra. It is the most populous city in India, and the fourth most populous city in the world, with a total metropolitan area population of approximately 20.5 million...

) in the late 1860s. She was ordered by the India Office
India Office
The India Office was a British government department created in 1858 to oversee the colonial administration of India, i.e. the modern-day nations of Bangladesh, Burma, India, and Pakistan, as well as territories in South-east and Central Asia, the Middle East, and parts of the east coast of Africa...

 for the Bombay Marine. The original specifications were thought to be too expensive and a cheaper design was ordered. While limited to harbour defence duties, the breastwork monitors were described by Admiral George Alexander Ballard
George Alexander Ballard
Admiral George Alexander Ballard, CB was an officer of the Royal Navy and a historian. Ballard was the eldest son of General John Archibald Ballard , and his wife Joanna, the daughter of Robert Scott-Moncrieff, and was born at Malabar Hill, Bombay on 7 March 1862...

 as being like "full-armoured knights riding on donkeys, easy to avoid but bad to close with." Aside from gunnery practice Magdala remained in Bombay Harbour for her entire career. The ship was sold for scrap
Ship breaking
Ship breaking or ship demolition is a type of ship disposal involving the breaking up of ships for scrap recycling. Most ships have a lifespan of a few decades before there is so much wear that refitting and repair becomes uneconomical. Ship breaking allows materials from the ship, especially...

 in 1903.

Design and description

In July 1866 the India Office asked for two floating batteries to defend Bombay and the Controller of the Navy, Vice Admiral
Vice Admiral
Vice admiral is a senior naval rank of a three-star flag officer, which is equivalent to lieutenant general in the other uniformed services. A vice admiral is typically senior to a rear admiral and junior to an admiral...

 Spencer Robinson
Robert Spencer Robinson
Admiral Sir Robert Spencer Robinson KCB was a British naval officer, who served as two five-year terms as Controller of the Navy from February 1861 to February 1871, and was therefore responsible for the procurement of warships at a time when the Royal Navy was changing over from unarmoured wooden...

 recommended that 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...

s be used. He recommended a design with 12 inches (30 cm) armour belt
Belt armor
Belt armor is a layer of heavy metal armor plated on to or within outer hulls of warships, typically on battleships, battlecruisers and cruisers, and on aircraft carriers converted from those types of ships....

 and 15 inches (38 cm) protecting the gun turret, armed with the largest possible guns, which would cost £220,000. The India Office thought that this was too expensive and ordered a repeat of instead for only £132,400.

The ships had an length between perpendiculars of 225 feet (68.6 m), a beam
Beam (nautical)
The beam of a ship is its width at the widest point. Generally speaking, the wider the beam of a ship , the more initial stability it has, at expense of reserve stability in the event of a capsize, where more energy is required to right the vessel from its inverted position...

 of 45 feet (13.7 m), and a draught of 15 in 3 in (4.65 m) at deep load. They displaced 3340 long tons (3,393.6 t). Their crew consisted of 155 officers and men.

Propulsion

Magdala had two horizontal direct-acting steam engines, made by Ravenhill, each driving a single propeller. The ship's boiler
Boiler (steam generator)
A boiler or steam generator is a device used to create steam by applying heat energy to water. Although the definitions are somewhat flexible, it can be said that older steam generators were commonly termed boilers and worked at low to medium pressure but, at pressures above this, it is more...

s had a working pressure of 30 pound per square inch. The engines produced a total of 1369 ihp on 21 October 1870 during the ship's sea trial
Sea trial
A sea trial is the testing phase of a watercraft . It is also referred to as a "shakedown cruise" by many naval personnel. It is usually the last phase of construction and takes place on open water, and can last from a few hours to many days.Sea trials are conducted to measure a vessel’s...

s which gave her a maximum speed of 10.67 knots (5.8 m/s). Magdala carried 220 long tons (223.5 t) of coal, enough to steam 450 nmi (833.4 km) at 10 knots.

Armament

The Cerberus-class ships mounted a pair of 10-inch
RML 10 inch 18 ton gun
The RML 10 inch guns Mk I - Mk II were large rifled muzzle-loading guns designed for British battleships and monitors. They were also fitted to the Bouncer-class flat-iron gunboats.-Design:...

 rifled muzzle-loading guns in each hand-worked turret. The shell of the 10 inches (254 mm) gun weighed 407 pounds (184.6 kg) while the gun itself weighed 18 long tons (18.3 t). The gun had a 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 1365 ft/s (416.1 m/s) and was credited with the ability to penetrate a nominal 12.9 inches (32.8 cm) 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...

 armour at 100 yards (91.4 m). The guns could fire both solid shot
Round shot
Round shot is a solid projectile without explosive charge, fired from a cannon. As the name implies, round shot is spherical; its diameter is slightly less than the bore of the gun it is fired from.Round shot was made in early times from dressed stone, but by the 17th century, from iron...

 and explosive 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...

. Magdala was rearmed in 1892 with four breech-loading BL 8-inch guns.

Armour

The Cerberus-class ships had a complete 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...

 waterline belt that was 8 inches (203 mm) thick amidships and thinned to 6 inches (152 mm) at the ends. The superstructure and conning tower
Conning tower
A conning tower is a raised platform on a ship or submarine, often armored, from which an officer can con the vessel; i.e., give directions to the helmsman. It is usually located as high on the ship as practical, to give the conning team good visibility....

 was fully armoured, the reason it was called a breastwork
Breastwork (fortification)
A breastwork is a fortification. The term is usually applied to temporary fortifications, often an earthwork thrown up to breast height to provide protection to defenders firing over it from a standing position...

, with 8–9 in (203.2–228.6 mm) of wrought iron. The gun turret
Gun turret
A gun turret is a weapon mount that protects the crew or mechanism of a projectile-firing weapon and at the same time lets the weapon be aimed and fired in many directions.The turret is also a rotating weapon platform...

s had 10 inches (254 mm) on their faces and 9 inches (228.6 mm) on the sides and rear. All of the vertical armour was backed by 9–11 in (22.9–27.9 ) 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 decks
Deck (ship)
A deck is a permanent covering over a compartment or a hull of a ship. On a boat or ship, the primary deck is the horizontal structure which forms the 'roof' for the hull, which both strengthens the hull and serves as the primary working surface...

 were 1.5 inches (3.8 cm) thick, backed by 10 inches (254 mm) of teak.

Service

HMS Magdala was laid down on 6 October 1868 by the Thames Ironworks
Thames Ironworks and Shipbuilding Company
The Thames Ironworks and Shipbuilding Company, Limited was a shipyard and iron works straddling the mouth of Bow Creek at its confluence with the River Thames, at Leamouth Wharf on the west side and at Canning Town on the east side...

 in Leamouth
Leamouth
Leamouth is the area to the west of the mouth of the River Lea at the River Thames at . The northern part of the area lies within a meander of the Lea; the southern part is bounded in the west by the former East India Docks, on two sides by the Lea and by the River Thames to the south...

, London
London
London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

. She was launched on 2 March 1870 and completed in November 1870. For her delivery voyage to India, Magdala was fitted with three temporary masts and made the trip under sail in the middle of winter without escort, as both her builders and the Royal Navy, considered her sufficiently seaworthy as to make the trip safely. Her life thereafter was wholly spent in Bombay Harbour, with occasional short trips to sea for firing practice. She was sold for scrap in January 1903.

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