The colorist, designed to correct the commonly held theory that red, yellow, and blue are the primary colors, and to supply the much needed easy method of determining color harmony; together with a system of color nomenclature and other practical information for artists and workers or designers in colors (1908)
Hatt, Joseph Arthur Henry, 1861- · New York, Van Nostrand · leaf 22
“ The Colorist ” By ]. A. H. Halt Harmony Chart No. I This Chart together with the mask is designed for the purpose of determining color harmonies. See directions on preceding pages. ( Patent applied for).
Color
Internet Archive · Getty Research Institute · Public domain (published before 1931). Free to use for anything.