Arthur Machen The House of Souls

"Let me tell you a tale so astonishing as to make you understand. A friend of mine met a fellow from York who had been traveling in the countryside when he came upon a farmhouse. The owner invited him in and told him a story of a man, a solicitor I recall, who came into possession of strange diary that related the last days of a young medical student who had discovered a previously unknown substance of such horrible properties that he began an investigation into its origins. Of these inexpl...