HMS Magdala (1870)

HMS Magdala was a Cerberus-class monitor breastwork monitor of the Royal Navy, built specifically to serve as a coastal defence ship for the harbour of Bombay (now Mumbai) in the late 1860s. She was ordered by the India Office 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 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 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 Spencer Robinson recommended that monitors be used. He recommended a design with 12 in armour belt and 15 in 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 HMVS Cerberus instead for only £132,400.

The ships had an length between perpendiculars of 225 ft, a beam of 45 ft, and a draught of 15 ft at deep load. They displaced 3340 LT. 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 boilers had a working pressure of 30 psi. The engines produced a total of 1369 ihp on 21 October 1870 during the ship's sea trials which gave her a maximum speed of 10.67 kn. Magdala carried 220 LT of coal, enough to steam 450 nmi at 10 knots.

Armament
The Cerberus-class ships mounted a pair of 10-inch rifled muzzle-loading guns in each hand-worked turret. The shell of the 10 in gun weighed 407 lb while the gun itself weighed 18 LT. The gun had a muzzle velocity of 1365 ft/s and was credited with the ability to penetrate a nominal 12.9 in of wrought iron armour at 100 yd. The guns could fire both solid shot and explosive shells. Magdala was rearmed in 1892 with four breech-loading BL 8-inch guns.

Armour
The Cerberus-class ships had a complete wrought iron waterline belt that was 8 in thick amidships and thinned to 6 in at the ends. The superstructure and conning tower was fully armoured, the reason it was called a breastwork, with 8 - 9 in of wrought iron. The gun turrets had 10 in on their faces and 9 in on the sides and rear. All of the vertical armour was backed by 9 - 11 in of teak. The decks were 1.5 in thick, backed by 10 in of teak.

Service
HMS Magdala was laid down on 6 October 1868 by the Thames Ironworks in Leamouth, London. 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.