in Thoreau’s Journal:

Whole weeks or months of my summer life slide away in thin volumes like mist or smoke—till at length some warm morning perchance I see a sheet of mist blow down the brook to the swamp—its shadow flitting across the fields which have caught a new significance from that accident.  And as that vapor is raised above the earth so shall the next weeks be elevated above the plane of the actual— Or when the setting sun slants across the pastures—and the cows low to my inward ear—and only enhance the stillness—and the eve is as the dawn—a beginning hour and not a final one—as if it would never have done—  With its clear western amber inciting men to lives of as limpid purity— Then do other parts of my days work shine than I had thought at noon—for I discover the real purport of my toil—As when the husbandman has reached the end of the furrow and looks back—he can best tell where the pressed earth shines most.