The BL 4-inch Mk IX naval gun was a British medium-velocity naval gun introduced in 1917 as secondary armament on the Renown-class battlecruisers and Glorious-class "large light cruisers", but which s
On Flower-class corvette HMCS Calgary in World War II
Original aft triple mounts on HMS Repulse c. 1916–1917
Coast defence gun and crew at Fort Crosby near Liverpool, UK, August 1940
Cleaning the breech on transport St Essylt, Suez 1942
The Courageous class consisted of three battlecruisers known as "large light cruisers" built for the Royal Navy during the First World War. The class was nominally designed to support the Baltic Proje
Courageous as a battlecruiser during the First World War
Right elevation and plan view of the Courageous class from Brassey's Naval Annual 1923
Furious had a single 18-inch gun fitted
Furious as originally completed