in Thoreau’s Journal:
There are a few inches of light snow on top of the little, hard and crusted, that I walked on here last, above the snow ice. The old tracks are blotted out, and new and fresher ones are to be discerned. It is a tabula rasa. These fresh falls of snow are like turning over a new leaf of Nature’s Album. At first you detect no track of beast or bird, and Nature looks more than commonly silent and blank. You doubt if anything has been abroad, though the snow fell three days ago, but ere long the track of a squirrel is seen making to or from the base of a tree, or the hole where he dug for acorns, and the shells he dropped on the snow around that stump.