From The Journal, July 23, 1851:
The mind is subject to moods, as the shadow of clouds pass over the earth. Pay not too much heed to them. Let not the traveller stop for them. They consist with the fairest weather. By the mood of my mind, I suddenly felt dissuaded from continuing my walk, but I observed at the same instant that the shadow of a cloud was passing over the spot on which I stood, though it was of small extent, which, if it had no connection with my mood, at any rate suggested how transient and little to be regarded that mood was. I kept on, and in a moment the sun shone on my walk within and without.