The Hesperides, the Nymphs of the Setting Sun, were the three sisters who lived in the extreme west near the edge of the ocean at the foot of Mount Olympus. Their primary purpose was to guard Hera’s garden where the golden apples grew. After Hercules successfully carried away the golden apples, they were turned into trees. Melville here refers to the painting by Renaissance artist Fra Angelico, The Garden of the Hesperides. Melville recalls the classical beauty of Fra Angelico’s painting.