Imagery in The Canterville Ghost
This is another example of Wilde bringing in a more serious tone as Sir Simon strives to terrify the Otises. This simile paints an image of how dark and haunting Sir Simon looks as he moves closer to his victims.
Wilde provides a little more seriousness and legitimacy to Sir Simon's ghostly actions in this passage by writing in some wonderful imagery to add to the tension of the scene. This is an example of personification, and it paints a vivid image for the readers of how even the moon is going to hide from the ghost's terrifying actions.