Johannes von Rheinfelden, Tractatus de moribus et disciplina humanae conversationis: id est ludus cartularum moralisatus
A fifteenth-century manuscript dated 1429 by Johannes von Rheinfelden, a moral treatise on conduct written in Latin, held by a Swiss library and digitised by e-codices. The pages are handwritten text in red and brown ink, with the first showing rows of small diagrams of triangles and polygons with labels beneath them, and the second showing a large triangle inside a circle above a row of smaller circled figures with lettering. For a designer, the value lies in the hand-ruled diagrams and red-ink headings as examples of medieval manuscript layout and geometric schematic drawing.
