First principles of symmetrical beauty
A treatise on aesthetic geometry by Edinburgh decorative painter and colour theorist David Ramsay Hay, published by Blackwood in 1846 for artists, architects and designers seeking mathematical rules of proportion. Its plates are fine-line engraved diagrams: triangles, ellipses and circles overlaid and labelled by class, number and angle in degrees, usable as spare linear motifs, grid systems or handwritten annotation.
