After the rain, the piano book moistens the wind, which means the fragrance of calligraphy.

This sentence means that after the rain, the piano sounds more pleasant when touched gently; The breeze blows, and the newly written calligraphy works exude a refreshing fragrance in the breeze.

This sentence is a couplet on the gallery of the west wing of Bailudong Academy in Lushan Mountain, which shows that the actions of the elegant people are related to piano, chess, calligraphy and painting.