in Thoreau’s Journal:

Here is our first spring morning according to the almanac. It is remarkable that the spring of the almanac and of nature should correspond so closely. The morning of the 26th was good winter, but there came a plentiful rain in the afternoon, and yesterday and to-day are quite spring like. This morning the air is still, and, though clear enough, a yellowish light is widely diffused throughout the east now just after sunrise. The sunlight looks and feels warm, and a fine vapor fills the lower atmosphere. I hear the phcebe or spring note of the chickadee, and the scream of the jay is perfectly repeated by the echo from a neighboring wood. For some days past the surface of the earth, covered with water, or with ice where the snow is washed off, has shone in the sun as it does only at the approach of spring, methinks. And are not the frosts in the morning more like the early frosts in the fall, ––common white frosts ?