Graphic representation of the periodic table of chemical elements in the style of parallel lines, with the single lines representing subshells and the groups of parallel lines representing different shells. This table was originated by Robert A. Steinberg in 1938 and classified by chemist Edward G. Mazurs as Type IIIC4-3 in his seminal work Types of Graphic Representation of the Periodic System of Chemical Elements (1957). A version of this illustration appears as Figure 95 on page 158 of Mazurs' 1957 publication.
Mazurs, Edward G., and Robert A. Steinberg. “Periodic Table in Style of Parallel Lines.” Glass, circa 1938–1957. Edward G. Mazurs Collection of Periodic Systems Images, Box 2. Science History Institute. Philadelphia. https://digital.sciencehistory.org/works/x633f154t.