Mechanism for lifting canal boats, 1796.
© Science Museum / Science & Society Picture Library
Engraving after a drawing by inventor Robert Fulton (1765-1815) entitled 'The Medium Plane for a small ascent', from his 'A treatise on the improvement of canal navigation' (London, 1796). The medium plane was designed to harnes the power of a water wheel to raise wheeled canal boats and their cargoes on metal tracks. Many canals were built in England in the late 18th century. Fulton was convinced that expensive locks and aqueducts were not necesary. He believed it would be cheaper to use small canals with inclined planes between different levels and cable viaducts over rivers. 'Tub and cistern' lifting motors provided the power. He also discused designs for iron and wooden bridges.