A sky without clouds is a meadow without flowers.—Journal, 24 June 1852
It will have some red stains, commemorating the mornings and evening it has witnessed; some dark and rusty blotches, in memory of the clouds and foggy, mildewy days that have passed over it; and a spacious field of green reflecting the general face of Nature,—green even as the fields; or a yellow ground, which implies a milder flavor,—yellow as the harvest, or russet as the hills. — "Wild Apples"—"Wild Apples"
Looking southward, the heavens were completely overcast, the mountains capped with clouds, and the lake generally wore a dark and stormy appearance, but from its surface six or eight miles distant there was reflected upward through the misty air a bright blue tinge from the unseen sky of another latitude beyond. — The Maine Woods—The Maine Woods
[N]o storms, no dust can dim its surface ever fresh;—a mirror in which all impurity presented to it sinks, swept and dusted by the sun's hazy brush,—this the light-dust cloth,—which retains no breath that is breathed on it, but sends its own to float as clouds high above its surface, and be reflected in its bosom still. — Walden—Walden
The most beautiful thing in Nature is the sun reflected from a tear-ful cloud.—Journal, 7 September 1851
The very willow-rows lopped every three years for fuel or powder,—and every sizable pine and oak, or other forest tree, cut down within the memory of man! As if individual speculators were to be allowed to export the clouds out of the sky, or the stars out of the firmament, one by one. We shall be reduced to gnaw the very crust of the earth for nutriment.—The Maine Woods
Waves of serener life pass over us from time to time, like flakes of sunlight over the fields in cloudy weather. In some happier moment, when more sap flows in the withered stalk of our life, Syria and India stretch away from our present as they do in history. All the events which make the annals of the nations are but the shadows of our private experiences. — A Week on the Concord and Merrimack Rivers—A Week on the Concord and Merrimack Rivers