The glass of time : the secret life of Miss Esperanza Gorst : narrated by herself / Michael Cox.

Enhanced descriptions from Syndetics:

Like its "beguiling" and "intelligent" (New York Times Book Review) predecessor, The Glass of Time is a page turning period mystery about identity, the nature of secrets, and what happens when past obsessions impose themselves on an unwilling present. In the autumn of 1876, nineteen year-old orphan Esperanza Gorst arrives at the great country house of Evenwood to become a lady's maid to the twenty-sixth Baroness Tansor. But Esperanza is no ordinary servant. She has been sent by her guardian, the mysterious Madame de l'Orme, to uncover the secrets that her new mistress has sought to conceal, and to set right a past injustice in which Esperanza's own life is bound up. At Evenwood she meets Lady Tansor's two dashing sons, Perseus and Randolph, and finds herself enmeshed in a complicated web of seduction, intrigue, deceit, betrayal, and murder. Few writers are as gifted at evoking the sensibility of the nineteenth century as Michael Cox, who has made the world of Charles Dickens and Wilkie Collins his own.