in Thoreau’s Journal:

To the river-side and Merrick’s pasture. The sun is up. The water in the meadows is perfectly smooth and placid, reflecting the hills and clouds and trees. The air is full of the notes of birds, song-sparrows, redwings, robins (singing a strain) bluebirds, and I hear also a lark, as if all the earth had burst forth into song. The influence of this April light has reached them, for they live out-of-doors all the night, and there is no danger they will oversleep themselves such a morning.  A few weeks ago, before the birds had come, there came to my mind in the night the twittering sound of birds in the early dawn of a spring morning––a semi-prophecy of it––and last night I attended mentally, as if I heard the spray-like dreaming sound of the mid-summer frog, and realized how glorious and full of revelations it was. The clouds are white, watery, not such as we had in the winter. I see in this fresh morning the shells left by the muskrats along the shore, and their galleries leading into the meadow, and the bright red cranberries washed up along the the shore in the old water-mark. Suddenly there is a blur on the placid surface of the waters, a rippling mistiness produced, as it were, by a slight morning breeze, and I should be sorry to show it to a stranger now. So is it with our minds.