While Da Vinci was a masterful artisan, he was also often employed as a military engineer. The revolving bridge was developed for quickly and moving troops across bodies of water that they might encounter in their path. This self-supporting bridge was light enough to be carried in pieces by soldiers and could be constructed without the need for any nails. The structure of the bridge was made of a rope and pulley system to allow it to rotate around a pylon on the shore to reach out across a river. While this invention didn't directly increase the military prowess of the armies that used it, it allowed troops to get from one place to another far faster than having to always go around large bodies of water.

Source: “What Is Leonardo's Revolving Bridge Invention?” Innovateus.net, www.innovateus.net/innopedia/what-leonardos-revolving-bridge-invention.

“Leonardo Da Vinci's Self Supporting Bridge.” Go Back to the Front Page, www.leonardodavincisinventions.com/leonardo-da-vinci-models/leonardo-da-....

Mahmoud, K.M. “Recent Developments In Bridge Engineering.” Google Books, books.google.com/books?id=7t3rGrDxA3oC&pg=PA85&lpg=PA85&dq=leonardo%2Bda%2Bvinci%2Bmovable%2Bbridge&source=bl&ots=rYjhsSuc1W&sig=xAYmz6N1i1X3ntSKlmTG9Y5Zqw8&hl=en&sa=X&ved=0ahUKEwjl_8irm8zZAhUJ7awKHQ5ABT44ChDoAQg0MAI#v=onepage&q=leonardo%20da%20vinci%20movable%20bridge&f=false.

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