Color-blindness : its dangers and its detection
A medical treatise by Boston ophthalmologist B. Joy Jeffries, published by Houghton, Osgood and Company in 1880, written for physicians and the general public on the dangers and detection of colour blindness. Its four pictures are plain line diagrams of overlapping bell-shaped curves over a spectral baseline marked R, O, Y, G, B, V, with numbered cone-sensitivity peaks, offering a designer a clear model for labelled charts and minimal scientific graphics.
