William Hope Hodgson's career as a writer of supernatural horror ended in the mundane horror of the Great War. In the preceding eleven years he had produced an oeuvre about which H. P. Lovecraft commented, in his essay Supernatural Horror in Literature:
Of rather uneven stylistic quality, but vast occasional power in its suggestion of lurking worlds and beings behind the ordinary surface of life, is the work of William Hope Hodgson, known today far less than it deserves to be. Despite a tendency toward conventionally sentimental conceptions of the universe, and of man's relation to it and to his fellows, Mr. Hodgson is perhaps second only to Algernon Blackwood in his serious treatment of unreality. Few can equal him in adumbrating the nearness of nameless forces and monstrous besieging entities through casual hints and insignificant details, or in conveying feelings of the spectral and the abnormal in connection with regions or buildings.
There, quite concisely, is a clue to what you'll encounter if you dip into Hodgson's books—although it's best to be careful what you start with, especially if you're not enamored of Edwardian prose. I recommend Carnacki the Ghost Finder, a collection originally serialized in The Idler. You could also call it "Ripping Ghost Stories" for the enthusiasm and purple-tinged prose. It's a quick read. But I guarantee that, with Carnacki, you will encounter things that you will never forget. When Hodgson is good, he's unbeatable.
The world in which Carnacki plies his trade as a ghost hunter and debunker (for some of the hauntings are hoaxes, for profit or revenge) shares with Lovecraft's the "suggestion of lurking worlds and beings behind the ordinary surface of life." But Lovecraft's horror is that of the completely other, so alien that it is virtually impossible for matter to mediate it in any way a human being can comprehend. Hodgson's other, alien as it is, manifests in more comprehensible ways; in the case of The Whistling Room, as a kind of "spiritual fungus" rotting a human soul, of which nothing remains but the desire for revenge. Or, in The Hog, another story in the collection, as the grunting of pigs, which Hodgson transforms into an unforgettable evocation of bestial malevolence that recalls, in its mindlessness, the horrid emptiness of the possessed physicist Weston in C.S. Lewis's Out of the Silent Planet.