Answer: on a stormy day / rainy day Maryland on a hay sack
Explanation: In Maryland one day, Amory is walking through the country reciting Poe when a sudden storm forces him to rush through a field looking for shelter. In one of the haystacks he hears someone singing Verlaine, a French poet. Eleanor asks who is walking through the field, and Amory responds that he is Don Juan and climbs up beside her on her haystack.
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