Thoreau writes in his journal:
These are remarkably warm and pleasant days. The water is going down, and the ice is rotting. I see some insects—those glow-worm-like ones—sunk half an inch or more into the ice by absorbed heat and yet quite alive in these little holes, in which they alternately freeze and thaw. At Willow Bay I see for many rods black soil a quarter of an inch deep, covering and concealing the ice (for several rods). This, I find, was blown some time ago from a plowed field twenty or more rods distant. This shows how much the sediment of the river may be increased by dust blown into it from the neighboring fields . . .