5. Chevreul (1786-1889) The Law of Simultaneous Colour Contrast , 1839 Principles of Harmony and Contrast of Colours and their Applications to the Arts , 1855 Hermann von Helmholtz (1821-1894) On the Relation of Optics to Painting & Handbook of Physiological Optics in 1867. Ogden N. Rood (1831-1902) Modern Chromatics, with Applications to Art and Industry, 1879, not translated into French until 1881.