The main British tank from 1923 until 1935
In 1923 Vickers Ltd. of Sheffield and Newcastle, started to manufacture tanks for the British Army. They were the first representatives of a new generation of tanks, designed to fight on the move and restore mobility to the battlefield The Medium Mark I was the first British tank in service with a sprung suspension and rotating turret. The Medium Mark II, which appeared in 1925, was an improved version of the Mark I. It was powered by an air-cooled Armstrong-Siddeley V8 engine.
As designed the Medium tanks had a 3 pounder gun in the turret; a Vickers machine-gun in each side of the hull and Hotchkiss light machine-guns in the turret. These last were later eliminated in favour of a single Vickers machine-gun, mounted alongside the main gun and described as co-axial, since it elevates on the same axis as the main gun. This modification altered the design from Mark II to Mark II* Using these tanks the Royal Tank Corps established standards of gunnery which, in their day, were never equalled.
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