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Stern winter's icy breath, intensely keen,
Now chills the blood, and withers every green;
Bright shines the azure sky, serenely fair,
Or driving snows obscure the turbid air.

A YEAR is a natural period, and the first imperfect year of ancient times must, no doubt, have arisen from observing the regular changes of heat and cold, of the leafing, flowering, and fruiting, of the various tribes of vegetables; and the agree ment of these appearances with the laying and hatching of birds, and the production of the young of quadrupeds. This way of reckoning, however, was subject to so many variations, that it was soon necessary to make choice of some more constant occurrence by which to mark the length of the year.

The ancients began their year in March, and it may appear singular, that modern civilized nations should choose to commence their year, at a period when nature lies

almost dormant,in preference to 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 fug 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 stores
Derived, thou sacred, all-invading power,

Myriads of little salts, or hook'd or strap'd
Like double wedges, and diffus'd immense,
Through water, earth, and ether?

Modern philosophers have, however, very generally taken the oppoisite side of the question; the little hooked salts, which in frosty mornings are found floating in the atmosphere, or adhering to the surfaces 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 more space 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 hard

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 lofty 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

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