Rolls-Royce Merlin prey, Rolls-Royce named the engine the "Merlin" after a small, Northern Hemisphere falcon ("Falco columbarius"). Two more Rolls-Royce engines developed just prior to the war were added to the company's range. The Rolls-Royce Peregrine was an updated, supercharged development of their V-12 Kestrel design, while the 42-litre (2,560 cu in) Rolls-Royce Vulture used four Kestrel-sized cylinder blocks fitted to a single crankcase and driving a common crankshaft, forming an X-24 layout. This was to be used in larger aircraft such as the Avro Manchester. Although the Peregrine appeared to be a satisfactory design, it was never allowed to mature since
Rolls-Royce Limited engine. When World War I broke out in August 1914, Rolls-Royce (and many others) were taken by surprise. As a manufacturer of luxury cars, Rolls-Royce was immediately vulnerable, and Claude Johnson thought the bank would withdraw its overdraft facility on which Rolls-Royce depended at that time. Nevertheless, believing that war was likely to be short-lived the directors initially decided not to seek government work making aero engines. However, this position was quickly reversed and Rolls-Royce was persuaded by the War Office to manufacture fifty air-cooled V8 engines under licence from Renault. Meanwhile, the Royal Aircraft Factory asked Rolls-Royce to design