When Sir Frank Whittle was developing his revolutionary jet engines during the 1940s, he needed robust but lightweight airframes to attach them to. Aluminium was the answer. Modern aviation could not have developed without this versatile, light and durable metal. The raw form of aluminium, bauxite, was first discovered in 1807 by Sir Humphry Davy (who also invented the famous miner's safety lamp) but it took years for scientists to develop it into a usable metal. By the late 19th century, aluminium was being used to make airship frames. By the 1920s, the first all-aluminium aircraft were flying.