Colour, a handbook of the theory of colour
Colour, a handbook of the theory of colour is a 1916 London technical handbook by George Henry Hurst, published by Scott, aimed at students and practitioners of colour theory. Its pictures are plain line charts of spectral energy curves plotted against letter-marked wavelength bands A to G, with hatched areas under each curve for pigments such as vermilion and chrome green; a designer might borrow the clean diagram style and the hatched-fill convention for showing light distribution.
