Note 179 — Chapter XXV · DYES AND DYEING.

The subject of colour is too complicated to be adequately treated here; and for fuller information, readers are referred to Abney’s ‘Colour Measurement and Mixture,’ S.P.C.K., London, 1891. It may, however, be pointed out that, while the true primary colour-sensations are unquestionably red, blue-green and violet, and by mixture of light of these colours, all other colours, including white, can be produced; the primary pigments or dyes are red, yellow, and blue; the effect being produced in the former case by the addition of colours, and in the latter by their subtraction.