The Girl in the Golden Atom by Raymond King Cummings

A classic work of science fiction, this novel was one of the first to explore the world of the atom. The Girl in the Golden Atom is the story of a young chemist who finds a hidden atomic world within his mother’s wedding ring. Under a microscope, he sees within the ring a beautiful young woman sitting before a cave. Enchanted by her, he shrinks himself so that he can join her world.