longer one directly over another, but often like silvery coins poured from a bag, one overlapping another, or in thin flakes, as if occupying slight cleavages. The beauty of the ice was gone, and it was too late to study the bottom. Being curious to know what position my great bubbles occupied with regard to the new ice, I broke out a cake containing a middling sized one, and turned it bottom upward. The new ice had formed around and under the bubble, so that it was included between the two ices. It was wholly in the lower ice, but close against the upper, and was flattish, or perhaps slightly lenticular, with a rounded edge, a quarter of an inch deep by four inches in diameter; and I was surprised to find that directly under the bubble the ice was melted with great regularity in the form of a saucer reversed, to the height of five eighths of an inch in the middle, leaving a thin partition there between the water and the bubble, hardly an eighth of an inch thick; and in many places the small bubbles in this partition had burst out downward, and probably there was no ice at all under the largest bubbles, which were a foot in diameter. I inferred that the infinite number of minute bubbles which I had first seen against the under surface of the ice were now frozen in likewise, and that each, in its degree, had operated like a burning-glass on the ice beneath to melt and rot it. These are the little airguns which contribute to make the ice crack and whoop.
At length the winter set in good earnest, just as I had finished plastering, and the wind began to howl around the house as if it had not had permission to do so till then. Night after night the geese came lumbering in the dark with a clangor and a whistling of wings, even after the ground was covered with snow, some to alight in Walden, and some flying low over the woods toward Fair Haven, bound for Mexico. Several times, when returning from the village at ten or eleven o’clock at night, I heard the tread of a flock of geese, or else ducks, on the dry leaves in the woods by a pond-hole behind my dwelling, where they had come up to feed, and the faint honk or quack of their leader as they hurried off. In 1845 Walden froze entirely over for the first time on the night of the 22nd of