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almost dormant, in preferenceto that season, when the race of vegetables and animals is actually renewed. In defence of the present custom, it may, however, be said, that the lengthening of the day, as it is the chief cause, so it is in fact the commencement of spring
So, little influence, however, has this change at first, that the month of January is usually found to be that in which the cold is most severe; there being little or no frost in this country before the shortest day, conformably to the old saying, “as the days begin to lengthen, the frost begins to strengthen." The weather is commonly either bright dry frost, or fog and snow, with cold dark showers, about the close of the month.
It used formerly to be a subject of much dispute among natural philosophers, whether frost was a substance, or merely the absence of a certain degree of heat. Thomson, in his Seasons, seems to be of the former opinion.
What art thou, Frost ? and whence are thy keen s:ores
Modern philosophers have, howe er, very generally taken the opposite side of the question; the little hooked salts, which in frosty mornings are found floating in the atmosphere, or adhering to the surface of bodies, being found by experiment to be nothing more than small crystals of ice, and capable of being melted by heat into pure water.
The principal difficulty here is, how comes it to pass that water, when deprived of its heat, should occupy
than it did before? for water, when frozen, is expanded, and hence ice is lighter than water, and swims upon it. If any one will observe the formation of ice, he will perceive, that it is composed of a number of needle-like crystals, that unite to each other, and that the space between these crystals is much more considerable than between the particles of water; and on this account, water, when frozen, occupies more space than before, though it receives no increase of weight. It may be also mentioned, that, in the act of freezing, a quantity of air is intercepted and fixed in the ice, which generally appears to be full of bubbles. It is from this disposition in water that, if a bottle full of water bard corked be set to freeze, the bottle will be broken for want of room for the expansion of the water while assuming its solid form. Water-pipes often burst from the same cause, and hoops fly off from barrels ; and in the intense frosts of Canada, it has been found, from experiments made at Quebec, that cannons and bomb shells filled with water, and the openings strongly plugged up, have in the course of a few hours been burst. This same property
of water when frozen, tends every year to diminish the bulk and height of the Alps and other Jofty mountains : the different crevices become filled with water during the summer, either from rain or the melting of the snow, which is frozen during the winter, and, by its irresistible expansive power, separates huge masses of rock from the summits of the mountains, and rolls them into the valleys below, to the terror of the inhabitants : for nothing but a wood is able to stop their impetuous progress. In its more moderate and minute effects, the operation of this general law is productive of a very beneficial consequence to the husbandman; for the hard clods of the ploughed fields are loosened and broken to pieces, by the swelling of the water within
then, when frozen; hence the earth is crumbled and prepared for receiving the seed in spring.
In North America, the river Niagara tumbles down a precipice nearly fifty yards in height, and the quantity of water constantly falling is so great, that the foam or spray may be seen hovering, like a cloud, over the spot at the distance of fifty miles ; in winter, the appearance of the waterfall is truly wonderful, the ice collects at the bottom in hills, and huge icicles, like the pillars of a large building, hang from the top of the fall, reaching nearly to the bottom.
Nothing, in fact, can be conceived more wonderful and striking than the effects of frost. To behold the liquid surface of the Jake changed into a firm marble-like pavement; to see the rapid river arrested in the midst of its course ; the headlong cas. cade, “ whose idle torreitts only seem to roar,” converted into a cluster of bright pillars of the strangest forms; or to view ihe intricate, varied, and beautiful feathery frosting that forms on our windows during a winter's nigbt; and all these effects produced by a rapid, silent, invisible power, cannot but strongly interest the observer. Some of these appearances, indeed, are so familiar to us, that we cease to regard them ; but it is only their being common, that causes them to be overlooked, as is evident from the surprise and admiration which they excite in persons, who, having been born and brought up in the WestIndies, or other hot climates, shew the greatest surprise and pleasure upon the first sight of these appearances.
In the year 1739 there occurred the most severe winter ever known in these Countries. The cold was so intense, that the Thames in London, and the Liffey in Dublin, were frozen completely over, so that crowds of people walked with safety on the ice; fires were made, and joints of meat roasted for the people ; so hard was the frost, that oaks of great size were split by it, the sap being turned to ice; beer and ale, and even wine, were frozen in the cellars into a hard mass of ice. In the year 1814 the winter was nearly as severe.
The cold in the more northern Countries is, however, far beyond what we experience here; in Russia, the rivers are covered with ice for five months of the year, and this is often three feet in thickpess, so as to bear heavy laden carriages with safety