Fifteenth century civil engineer, artist, biologist and philosopher Leonardo da Vinci typifies the breed of Italian intellectual now described as a Renaissance Man. He lived at the time when Italy was re-emerging as a growing cultural force in Europe following the collapse of the Roman empire.
Leonardo may be best known as a painter, but he also did a great deal of original thinking about technical problems faced by civil and structural engineers.
Although he lacked a formal education, Leonardo's fascination for engineering led him to look hard at basic engineering theory. He was interested in economy of structural design, and developed new theories on the behaviour of arches and beams.
Leonardo also produced designs for a truss bridge and a pedestrian swing bridge with the top of a bow string arch forming the deck.
He even got involved in town planning while working in the court of Ludovico Sforza, the ruler of Milan. In 1483 the city was struck by a plague and he came up with plans for new townships incorporating extra wide streets to avoid traffic congestion.
Leonardo's interest in civil engineering also spilled over into mechanics. His manuscripts show numerous drawings of excavating cranes for digging canals and locks as well as designs for military equipment ranging from machine guns and catapults.
Hydraulic engineering also occupied him, particularly the behaviour of waves and eddies in rivers. He developed several plans for canals and irrigation schemes in northern Italy.
Leonardo's more ambitious projects were never built. One, a navigational canal linking Florence with Pisa and the sea did get started at the end of the 15th century. It was eventually abandoned in 1504 after frequent military attacks ordered by Pisa's rulers, who were opposed to the project.
He also came up with a plan to drain the Pontine Marshes by deepening and regulating the flow of the Martino river and cutting another outlet to the sea. The proposal was later put into action by another Italian engineer, Giovanni Scotto, and was such a success that it sparked a series of legal battles over the ownership of the newly reclaimed, fertile land.
Much of Leonardo's work was never completely finished. He appears to have spent his life flitting between a wide range of projects, theories and painting commissions. As a result, most of his theories amounted to little more than copious jottings whose significance was only later realised by historians.