A clear predecessor to the early 20th century "weird" fiction of Lovecraft or Ashton Smith, PAN might actually be MORE readable than those two or their contemporaries. It doesn't have the big, crashing climax we expect from horror, preferring a quiet mounting dread as the tale of years and broken lives unfolds.

It's not perfect, could be longer, and the e-book version I read had a few formatting issues that removed me from the story. Trivial issues.

Snag a copy, an hour of quiet by a fireplace or in that big chair near a window on a stormy day, and enjoy a classic horror story.