Stanhopes are microphotographs fitted into a tiny hole with a lens that allows you to view them when held up to the light. Most were sold as novelty souvenirs, often fitted into a useful object like a sewing tool, letter opener, pencil or into jewelry. Ironically, although they are named after Lord Charles Stanhope, who did in fact invent a lens, the actual lenses used are Codding Magnifiers, invented by Lord David Brewster. More history here.
