Villard de Honnecourt’s Diagram, found on The Secret Law of Page Harmony, which is a great resource and very helpful indeed.

Practicing in 13th century France, Honnecourt was an architect who used a similar principle to design the pages of his Workshop Record Book that he did when working on his structures.

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This is a moment in which the boundaries separating graphic design and architecture were blurred, showing that the development of pleasing ratios, shapes and sizes is not dependent on the medium, but the mind.