A hand-powered, crank-driven, milling machine. Engraving, 174-. https://www.rawpixel.com/image/13997973/hand-powered-crank-driven-milling-machine-engraving-174Free Image from public domain license
Detail of the Cologne cathedral. Digitally enhanced from our own original 1888 edition from L'ornement Polychrome by Albert… https://www.rawpixel.com/image/329000/free-illustration-image-lornement-polychrome-vintage-germanyFree Image from public domain license
Rickendorf, near Cologne, Germany. Part of a villa colony. Sourced from the Library of Congress. https://www.rawpixel.com/image/12249749/image-plant-person-skyFree Image from public domain license