A story by HP Lovecraft inspired by Arthur Machen's "The Novel of the White Powder" (from the novel The Three Imposters). The story is first told from the perspective of a property investigator visiting the town of Arkham who is citing for a new reservoir to be built. Eventually he starts asking about the mysterious "blasted heath" which the people had been trying to avoid talking about for the entire time. Eventually he finds Ammi, an old man living near the heath, who is willing to explain what happened there and why absolutely nothing can live on that plot of land. Can be read here.