Answer:
If the night was moist black velvet, the night air must be very humid and damp. It might also be pitch black out, so it would probably be very late out in the summer time, like 9PM - 3AM, or it could be anywhere from 6PM - 6AM in the winter months. Also, the word velvet compares the dark humid night to the moist black velvet, where visibility is low and nothing can be seen clearly. Velvet is a smooth texture, slippery and moist but compact and hard to see through. It perfectly relates to trying to look through a velvety texture. is describing the smooth texture of night. To me this means that the narrator is describing the night as a humid, smooth night.
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