The House on the Borderland by William Hope Hodgson
In 1877, two gentlemen, Messrs Tonnison and Berreggnog, head into Ireland to spend a week fishing in the village of Kraighten. While there, they discover in the ruins of a very curious house a diary of the man who had once owned it. Its torn pages seem to hint at an evil beyond anything that existed on this side of the curtains of impossibility. This is a classic novel that worked to slowly bridge the gap between the British fantastic and supernatural authors of the later 19th century and modern horror fiction. Classic American horror writer H. P. Lovecraft lists this and other works by Hodgson among his greatest influences.