It is a fact, established equally by common experience and by numerous experiments, that water, in freezing, expands. It is generally estimated that 8 cubic inches of water, become 9 by the act of congealing. The expansion is attributed, with sufficient evidence, to a crystalline arrangement arising from a kind of polarity in the particles of water exerted when they are near congealing, by which they attract one another in certain points, and not in others. Dr. Black, with his usual felicity, has illustrated this tendency, by supposing a great number of small magnetized needles, thrust through corks, so that they will float parallel to the surface of water, to be thrown promiscuously into a vessel of that fluid. They will not remain in the situation in which they are thrown in, but, in consequence of their polarity, attractions and repulsions will be immediately exerted; they will rush together, with a force equal to the overcoming of a certain resistance; they will arrange themselves in pairs and groups, and finally, in a connected assemblage. The particles of water attract each other with a prodigious force, when resistance is opposed; for it is well known that domestic utensils, trees, rocks, and even cannon, and bomb-shells, are burst with explosion, when water confined within them is frozen. There is force enough then exerted by the expansion of freezing water, to produce all the mechanical violence, whose effects were so striking in the instance at Deerfield. In the common cracking of the ground by frost, so extensively observed in cold climates, the effect appears to result in the following manner. The water contained in the ground, (that is, in that part which is within the reach of a freezing temperature) by congealing, expands and demands more space; a movement must necessarily take place in the direction where there is the least resistance; this will evidently be upward, because the atmosphere, the only counteracting power in this direction, cannot resist the expansion of the freezing water as much as it is resisted by the earth below the freezing stratum. Consequently, the freezing earth is forced upward, but being of unequal strength in different places, it cracks at the weakest spot; and the earth, for some distance on the sides of the fissure, is thrown into the position of two planes gently inclined, their relative position resembling that of a very flat roof, and the more they are lifted by frost, the more they will decline from one another, and the wider will be the fissure. But why, in the instance which Mr. Hitchcock has related, did they overlap? The explanation appears to result from the circumstances of the case, as far as they can be understood without ocular inspection of the ground.