Researches in colour vision and the trichromatic theory
A 1913 London scientific treatise by Sir William de Wiveleslie Abney, published by Longmans, Green, on colour vision and the trichromatic theory for researchers and students of optics. Its pictures are black-ground graphs with white curves plotted over fine square grids, showing luminosity and extinction against wavelength scales, with labelled spectral lines and curves a designer could read as a clean, technical diagram style.
