Colour Theory

“Key to the Meanings of Colours” from the 1901 book <n>Thought-Forms</n> by <n>Annie Besant</n> and <n>C.W. Leadbeater</n>.

<n>Plate 3 from An Essay on Light and Shade</n> (1805), a watercolour and etching by <n>Mary Gartside</n>.

<n>Farbenkugel</n> (Color Sphere), an 1810 illustration by German Romantic painter <n>Philipp Otto Runge</n>.

<n>Johann Wolfgang von Goethe</n>'s 1809 color wheel diagram from his book, <n>Theory of Colours</n>.

<n>Tobias Mayer's Color Triangle</n> from 1775, published by <n>Georg Christoph Lichtenberg</n>.

The <n>Prismatic colour wheel</n> from <n>The Natural System of Colours</n> by <n>Moses Harris</n>, 1766.

<n>Parsons' Spectrum Color Chart and Value Scale</n> by <n>Frank Alvah Parsons</n>, published in 1920.