HMS Mersey
History
Brazil
Name	Madeira
Builder	Vickers
Laid down	24 August 1912
Launched	30 September 1913
Out of service	3 August 1914
Fate	Sold to the United Kingdom
United Kingdom
Name	HMS Mersey
Acquired	3 August 1914
Fate	Sold 1921 for scrapping
General characteristics
Class and type	Humber-class monitor
Displacement	1,260 long tons (1,280 t)
Length	266 ft 9 in (81.3 m)
Beam	49 ft (14.9 m)
Draught	5 ft 7.2 in (1.7 m)
Installed power	1,450 ihp (1,080 kW)
Propulsion	2 × triple expansion engines 2 × Yarrow boilers 2 × screws
Speed	12 kn (22 km/h; 14 mph)
Complement	140
Armament	2 × 6 in (152 mm) guns 2 × 4.7 in (119 mm) howitzers 4 × 3-pounder guns 1 × 3-pounder anti-aircraft gun
Armour	Belt: 1.5–3 in (38–76 mm) Bulkheads: 1.5 in (38 mm) Barbette: 3.5 in (89 mm) Turret Face: 4 in (102 mm)

HMS Mersey was a Humber-class monitor of the Royal Navy. Originally built by Vickers for Brazil and christened Madeira, she was purchased by the Royal Navy in 1914 on the outbreak of the First World War along with her sister ships Humber and Severn.

Service history

Mersey had a relatively successful career in the First World War and had two prominent incidents. At the Battle of the Yser in 1914, off the coast of Belgium, she bombarded German troops as well as artillery positions. In July 1915, she was towed to the Rufiji River delta in German East Africa, where she and Severn then assisted in the destruction of the German light cruiser Königsberg.^{[note 1]}

The monitor later went to the Mediterranean and served on the River Danube.

Five crew died between January 3 and January 6, 1919. They are buried at the Commonwealth War Graves Commission Bucharest War Cemetery.

In 1921, she was sold to the breakers.

Battle honours

• Battle of the Yser 1914–1915
• SMS Königsberg 1915