There was one scene that was truly horrific, but the novel isn't to be remembered by the splash or gore or rising action. It is truly excellent for it's archetypal characters that never felt corny, its complex plot, its clever pacing and believable rationelle. It was a haunted house novel, but easily a head above any that I've read. I feel the pressure from the novel that probably ushered in whole generations of new horror novels and especially horror movies, intelligent and scary and beautiful. 
 It's reliance on sex to horrify might not date as well as modern novels, but the novel is definitely a classic.