'The Mill Mystery' by Anna Katharine Green is a terrific read Published in 1886, it reflects many of the characteristics of popular gothic mysteries of the time, but it features a woman detective, Constance Sterling, an orphan who is between jobs. Constance is not actually a detective in the sense of modern mysteries. She is a simply a young poor but respectable woman of 25 years of age who, in accepting a job as a nurse to a dying wealthy matriarch of a sketchy family, the Pollards, becomes embroiled in the middle of the family's effort to hide a devastating secret. However, she feels it is her duty to unravel the various threads wherever they lead - she has made a deathbed promise to her hapless roommate and best friend, Ada Reynolds. The Pollards may have something to do with Ada's sudden death, as well as the mysterious demise of her fiance Mr. Barrow, whose body was found in an abandoned mill at the bottom of a vat. Of course, the handsome and intriguing eldest Pollard son, Dwight, whose occasional brooding presence in the dying Mrs. Polllard's bedroom has nothing to do with Constance's sudden fits of heart palpitations. She is certain it is only the terrifying atmosphere of threat surrounding the family and old dark Victorian mansion.