The Underground City by Jules Verne; includes 45 illustrations by Jules-Descartes Férat. Also published as The Child of the Cavern; or Strange Doings Underground, Black Diamonds, Black Indies, Child of the Cavern, or Strange Doings Underground.
The fortunes of the mining community of Aberfoyle near Stirling, Scotland. Receiving a letter from an old colleague, mining engineer James Starr sets off for the old Aberfoyle mine, thought to have been mined out ten years earlier.
Starr finds mine overman Simon Ford and his family living in a cottage deep inside the mine. Mysterious and unexplained happenings start to occur around the main characters, attributed initially to goblins and fire-maidens. Suspicious, Harry continues his explorations of the cavern system, where down a deep shaft, he discovers a young orphan girl named Nell.
Over the course of the next few years Nell is adopted by Simon and Madge but reveals nothing of where she came from, only that she had never been out of the mine.