Da Vinci, Leonardo. Codex Atlanticus, studies for the tiburio of Milan Cathedral. c. 1487. Drawing. Biblioteca Ambrosiana, Milan, Italy. Architects’ Drawings: A Selection of Sketches by World Famous Architects Through History. Amsterdam: Elsevier/Architectural, 2005. 26. Print.
The image above is a design sketch of the Milan Cathedral. Fold marks indicate lines of symmetry, and the small visible dots are pin holes. It is thought that da Vinci, used the combination to ensure symmetry (Smith 27).
Da Vinci, Leonardo. Military Machines. c. 1947. Drawing. British Museum, London, United Kingdom. ArtStore. Web. 04-04-2017.
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