Thoreau writes in his journal:
I observed this morning that the ice at Swamp Bridge was checkered with a kind of mosaic-work of white creases or channels; and when I examined the under side, I found it to be covered with a mass of crystallizations from three to five inches deep, standing, or rather depending, at right angles to the true ice, which was about an eighth of an inch thick. There was a yet older ice six or eight inches below this. The crystals were for the most part triangular prisms with the lower end open, though, in some cases, they had run into each other so as to form four or five sided prisms. When the ice was laid upon its smooth side, they resembled the roofs and steeples of a Gothic city, or the vessels of a crowded haven under a press of canvas.
I noticed also that where the ice in the road had melted and left the mud bare, the latter, as if crystallized, discovered countless rectilinear fissures, an inch or more in length—a continuation, as it were, of the checkered ice.
