The lines that show an omniscient narrator are: “The garden outside was like a tray made of beaten brass, flattened out on the red gravel and the stony soil in all shades of metal—aluminum, tin, copper, and brass.”
This refers to a person that makes narration with the all-knowing and all-seeing knowledge as he knows the thoughts, feelings, and actions of characters in a story.
From the complete text, there is the narration that shows the use of an omniscient narrator which shows the description of the garden outside and surrounding environment.
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