Light and colour theories and their relation to light and colour standardization
This 1915 London and New York scientific treatise by Joseph Williams Lovibond, a colour-measurement authority, was written for physicists, lighting engineers and colour specialists studying light and standardized colour. Its single plate is a rotated printed chart of Chart 4, plotting a luminosity or colour-rating curve against stand or feet of lamp-to-screen distance, with four lines of plotted points drawn in plain black on white and a small boxed key. A designer could take its clean, sparse data-graph layout and thin rule lines as a model for technical diagrams.
