October 11, 1852 in Thoreau’s Journal:
Now it is true autumn—all things are crisp & ripe.
October 11, 1859:
The note of the chickadee heard now in cooler weather & above many fallen leaves––has a new significance.
There was a very severe frost this Am prob ground stiffened a chestnut-opening frost. A season-ripener––opener of the burrs that enclose the Indian summer–– Such is the cold of early or mid October. The leaves and weeds had that stiff hoary appearance.