HMS ''Waterwitch'' was one of only three armoured gunboats built for the Royal Navy. Uniquely, she was powered by Ruthven's "hydraulic propeller", making her the first ship to employ waterjets. She was launched in 1866 and conducted comparative trials with her two sister ships. She was not employed operationally and was sold in 1890.

Design

Designed by the Rear Admiral George Eliot and the Controller's Department, ''Waterwitch'' was a half-sister to and , and all three were built mostly as experimental vessels. While ''Viper'' and ''Vixen'' were twin screw vessels, ''Waterwitch'' had a water-pump propulsion system. ''Vixen'' was almost identical to ''Viper'', but was of composite construction.

Hull

''Waterwitch'' was an armoured gunboat of the breastwork type, with a hull constructed of iron. Her armour plating was backed by of teak and extended for about amidships. The bottom of the armoured box extended below the waterline and up to the upperdeck. The forward and aft ends of the box were similarly armoured, although the front end also extended upwards by a further . In addition, a waterline armoured belt extended for the whole length of the vessel. She and her two sisters were the only armoured gunboats ever built for the Royal Navy. Unlike her sisters, she was fitted with a bow rudder as well as the traditional stern rudder.

Sail plan

She was equipped with a barquentine rig.

Armament

''Waterwitch'' was armed with two 7-inch (6½-ton) muzzle-loading rifled guns and two 20-pounder breech-loading rifled guns.

Propulsion

''Waterwitch''s unique propulsion system was essentially a vast centrifugal steam-powered pump which drew water from sluices in the centre of the vessel and ejected it in jets from adjustable nozzles. Two sets of nozzles were provided, one for ahead propulsion and one for astern propulsion.Journal of the Franklin Institute By Persifor Frazer, Franklin Institute, Philadelphia (1866)
p.396 Steam was provided by two Maudslay iron fire-tube boilers fed from six furnaces. The horizontal Ruthven "hydraulic reaction engine" was manufactured by

J & W Dudgeon J & W Dudgeon was a Victorian shipbuilding and engineering company based in Cubitt Town, London, founded by John and William Dudgeon. John and William Dudgeon had established the ''Sun Iron Works'' in Millwall in the 1850s, and had a reputatio ...

and comprised a wheel in diameter weighing and contained within a case across. The wheel was rotated by three steam cylinders and developed . The hopes of safety, performance and control that were expected from this propulsion were summed up by Mr. M. W Ruthven:

Construction

''Waterwitch'' was ordered from the Thames Ironworks and Shipbuilding Company on 29 October 1864 and laid down the same year. She was launched on 28 June 1866 and commissioned on 26 June 1867 under Commander Philip Ruffle Sharpe. for comparative trials.

Career

''Vixen'', ''Viper'' and ''Waterwitch'' conducted comparative trials at Stokes Bay in the Solent the late 1860s. Although turning ability was impressive, and ''Waterwitch'' most impressive of all in this respect, none of the ships attained more than in an era when could achieve .Richard A Gould, ''The archaeology of HMS'' Vixen'', an early ironclad ram in Bermuda'', The International Journal of Nautical Archaeology (1991) 20.2: 141-153
(Subscription required) She was inspected by the American admiral commanding the European Squadron, Admiral David Farragut in 1867. None of the armoured gunboats performed well in the trials because of their inefficient hull form. ''Waterwitch'' was no worse than ''Viper'' or ''Vixen'' in the speed trials and manoeuvred impressively. Nevertheless, a huge internal volume was required for the internal "hydraulic propeller"The Hydraulic Propeller, A Description of this Novel Propelling Device, and an Account of its Performance
'' New York Times'', 13 January 1868 and there was little in favour of this early form of jetboat over the then nearly ubiquitous screw propulsion. She carried out inclining tests in Keyham Basin, Devonport on 16 March 1871. She seems to have spent much of the rest of her life as a test bed alongside in Portsmouth.

Fate

Placed on the non-effective list long before disposal, she was sold to Castle for breaking at Charlton on 26 April 1890.

Citations

References

* * * {{DEFAULTSORT:Waterwitch (1866) Gunboats of the Royal Navy Victorian-era gunboats of the United Kingdom Ships built in Leamouth 1866 ships