The figurative language device in the bolded text is a simile. A simile is a figure of speech that compares two unlike things using the words "like" or "as". In this case, the text states that Heathcliff's face was as white as the moon. The comparison between Heathcliff's face and the moon helps to create a vivid image in the reader's mind and adds depth to the description.
Similes are commonly used in literature to enhance descriptions, create imagery, and evoke emotions within the reader. They allow the author to make comparisons and draw parallels between different elements in the text.
In this particular simile, the comparison between Heathcliff's face and the moon suggests that his face was pale, possibly indicating a state of shock or fear. It helps to convey the intensity of his emotions in that moment.
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