Robert W. Chambers 
In Search of the Unknown [PDF ebook] 

Though his later novels took a turn toward political and romantic matters, Robert W. Chambers’ early works mined a unique vein of the horror genre that has come to be known as "weird" fiction. Though he soon abandoned his literary ambitions in this direction, his early works gained a large following, including admirers such as H.P. Lovecraft, who regarded the horror novel In Search of the Unknown as one of the best works in the genre.