Haunted Man and the Ghost's Bargain

Redlaw is a teacher of chemistry who often broods over wrongs done him and grief from his past.
He is haunted by a spirit, who is not so much a ghost as Redlaw''s phantom twin and is "an awful likeness of himself...with his features, and his bright eyes, and his grizzled hair, and dressed in the gloomy shadow of his dress..." This specter appears and proposes to Redlaw that he can allow him to "for...