in Thoreau’s Journal:

It is a very fine afternoon to be on the water, somewhat Indian-summer-like. I do not know what constitutes the peculiarity and charm of this weather; the broad water so smooth, notwithstanding the slight wind, as if, owing to some oiliness, the wind slid over without ruffling it. There is a slight coolness in the air, yet the sun is occasionally very warm. I am tempted to say that the air is singularly clear, yet I see it is quite hazy. Perhaps it is that transparency it is said to possess when full of moisture and before or after rain. Through this I see the colors of trees and shrubs beginning to put on their October dress, and the creak of the mole cricket sounds late along the shore.