Thoreau writes in his journal:
P.M.—To Cliffs . . .
There is considerable growth in the water at the Boiling Spring . . . Saw a bullfrog in Hayden’s pond-hole and a small green grasshopper . . .
It is remarkable how scarce and silent the birds are even in a pleasant afternoon like this, compared with the morning. Within a few days the warblers have begun to come. They are of every hue. Nature made them to show her colors with. There are as many as there are colors and shades . . .