Elenco Swing Bridge - Manual (Page 9)

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Da Vinci designed a revolving bridge for Duke Sforza, of Milan. The bridge would
swing across a stream or moat and set down on the other side so that soldiers
could pass with little trouble. Da Vinci designed this revolving bridge using light
materials, affixed to a rolling rope-and-pulley system that would allow an army
to pick up and go at a moment's notice.
Da Vinci’s also designed bridges to guard against advancing enemies. One of his
bridge designs lets the span swing around a piling separating it form the shore to
prevent opposing military units from crossing the river.
Leonardo drew plans for a single-span bridge, but never saw it built in his lifetime.
At the time, no one believed his bridge could work especially without the usual
support piers to hold up the center. In 1781, Thomas Pin exhibited a model in
Benjamin Franklin’s garden. He too, did not convince his observers that the bridge
would work.
Da Vinci also illustrated that triangular truss bridges would resist tension better
than the older box structures and proposed a two-level truss bridge with the bottom
for vehicles and transportation and the top for pedestrians.
Da Vinci’s plans for the Gold Horn Bridge, designed for Sultan Bajazet II of
Constantinople (Istanbul) were resurrected by a Norwegian artist five centuries
after they were drawn. The artist undertook the project to build the bridge,
as homage to Da Vinci. The span is situated in Norway and opened to foot and
bicycle traffic on October 31, 2001. The artist, Vebjørn Sand, is currently
considering several sites in the United States for the next Leonardo Bridge Project.
DID YOU KNOW?
Revolving Bridge