The principles of beauty in colouring systematized
A treatise on colour harmony by Edinburgh decorative painter and theorist David Ramsay Hay, published by W. Blackwood and Sons in 1845 for house painters, decorators and students of aesthetics. Its plates are hand-coloured hexagonal diagrams of six triangular segments around a lettered star core, giving muted olive, maroon, ochre and indigo palettes and geometric colour-wheel layouts.
