Yon's steam airship design. 19th-century illustration of the 1886 steam-powered hydrogen airship design of French engineer Gabriel Yon, similar to the airship built in 1852 by French engineer and aeronaut Henri Giffard (see C009/8300). Yon's improved design was 60 metres long and would have attained speeds of 40 kilometres per hour. The propeller was driven with a steam engine that had a funnel that pointed downwards. However, the design was never built. Artwork from 'Aerostation - Aviation' (1911) by French civil engineer Max de Nansouty (1854-1913), part of the 'Les merveilles de la science' series of 1867-1891 by Louis Figuier.