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and is affected so much by accidental circumstances, as to preclude the possibility of an exact calculation; that now the year does not commence till ten days after the winter solstice, and 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 intense; 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 showers about the close of the month.
It used formerly to be a subject of much dispute among natural philosophers, whether frost was a particular 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
Modern philosophers have, however, very generally embraced the opposite side of the question; the little "hooked salts, or spicule, 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, capable of being resolved by heat into pure water.
The principal difficulty in the theory is, that if frost be only the absence of heat, 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. The following explanation, however, will sufficiently account for this fact, without supposing that frost is a substance, which by an union with water increases the bulk of it. If any one will observe the process of the formation of ice, he will perceive that it is composed of a number of needle-like crystals that unite to each other at angles of a certain size; hence 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 also be mentioned that, in the act of congelation, 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 to crystalise at angles of a particular measurement 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 apertures 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 fissures and 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 detaches 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 and accelerated 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 them when frozen: hence the earth is crumbled and prepared for receiving the seed in spring.
Nothing can be conceived more wonderful and striking than the effects of frost. To behold the liquid surface of the lake changed into a firm marble-like pavement; to see the rapid river arrested in the midst of his course, the headlong cascade, "whose idle torrents only seem to roar," converted into a cluster of translucid pillars of the most grotesque forms; or to view the intricate, varied, and beautiful crystalisations that form on our windows during a winter's night;—and all these effects produced by a rapid, silent, invisible agency, 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 frequency 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 West Indies or other hot climates, behold these phenomena for the first time.
Here glittering turrets rise, upbearing high
(Fantastic mis-arrangement) on the roof
Large growth of what may seem the sparkling trees
And shrubs of fairy-laud. The crystal drops
That trickle down the branches, fast congealed,
Shoot into pillars of pellucid length,
And prop the pile they but adorned before.
Here grotto within grotto, safe defies
The sunbeam. There imbossed and fretted wild
The growing wonder takes a thousand shapes
Capricious, in which Fancy seeks in vain
The likeness of some object seen before.
Cowpeb, Taak, v.
Snow is the water of clouds frozen. On a close examination it is found to be composed of icy darts or stars united to each other, as all crystals of water are, whether they compose ice, snow, or hoar-frost, at angles of 60 or 120°. Its whiteness is owing to the small particles into which it is divided, refracting and reflecting, instead of transmitting all the rays of light that fall upon it. Ice, when pounded, becomes equally white. Snow is useful, by covering the plants, and protecting them from the severity of the frost; keeping them very dry, and at a certain depth under the snow the cold continuing always of the same moderate temperature, namely, at 32°, or just at the freezing point. It is, however, a very fatal enemy to shrubs that grow in a southern aspect, for the heat of the sun at noon partially melts the snow, which by the cold of the following night is converted into a mass of ice, and thus destroys the most flourishing and hardy plants; and it has frequently been found by experience in severe winters, that those vegetables which have been exposed to the rays of the sun have been almost totally cut off, while those under a north shelter have sustained no injury.
Hail-stones are drops of rain suddenly congealed into a hard mass, so as to preserve their figure. They often fall in the warmer seasons of the year, as at all times the upper parts of the atmosphere are very cold.
Hoar-frost is dew or mist frozen. It adheres to every object on which it falls, and produces figures of incomparable beauty and elegance. Every twig and blade of grass is beset by it with innumerable glittering pearly drops, or silvery plumage, beyond the skill of any artist to imitate.
Sometimes it happens that a sudden shower of rain falls during a frost, and immediately turns to ice. A remarkable scene is then produced, which the following lines beautifully describe.
Ere yet the clouds let fall the treasured snow,
Or winds begin through hazy skies to blow,
At evening a keen eastern breeze arose,
And the descending rain unsullied froze.
Soon as the silent shades of night withdrew,
The ruddy morn disclosed at once to view
The face of nature in a rich disguise,
And brightened every object to my eyes;
For every shrub, and every blade of grass,
And every pointed thorn seemed wrought in glass.
In pearls and rubies rich the hawthorns show,
While through the ice the crimson berries glow;
The thick-sprung reeds the watery marshes yield,
Seem polished lances in a hostile field;
The stag, in limpid currents, with surprise
Sees crystal branches on his forehead rise;
The spreading oak, the beech, and tow'ring pine,
Glazed over, in the freezing ether shine;
The frighted birds the rattling branches shun,
That wave and glitter in the distant sun,
When, if a sudden gust of wind arise,
The brittle forest into atoms flies:
The crackling wood beneath the tempest bends,
And in a spangled shower the prospect ends.
Philips, Lett, from Copenhagen.
In such a case prodigious mischief has been done in the woods by the breaking down of vast arms of trees, which were overloaded by the weight of the incrusting ice; and even rooks, attempting to fly, have been taken, owing to their wings being frozen together by the sleet that congealed as it fell.
The inclemency of the season is shown by its effects on animals. Those which are called the cold-blooded, that is, where the whole of the blood does not circulate through the lungs, as the frog, the snake, and the lizard, are benumbed by it in their winter quarters, and continue in this death-like state till the return of warm weather. Others, as the dormouse, the marmot, and bear, sleep away the greater part of this uncomfortable period; while others, as the squirrel and field-mouse, which lay up stores of provision during the autumn, keep close in their retreats, sleeping a good deal during the intensity of the frost, but, during the less severe part of the winter, being in an active state, have recourse to their hoards for a supply of subsistence. But animals in a state of sleep require nourishment, though not in such large quantities as those which continue actively alive; the necessity of food being proportioned to the rapidity of the circulation of the blood. Since, however, in a state of torpor it is impossible to take in nourishment, these animals must perish, were it not for a store of food prepared and laid up within them in the form of fat: for animals of this class become very fat before they retire to their winter habitations, and come out again in the spring lean and emaciated, as is the case with the bear, marmot, etc. With respect to the cold-blooded animals, which accumulate no fat, the continuance of their life is provided for by other means. All these animals are capable during their active state, of supporting the want of food for a great length of time; at which period the pulsations of the heart, which is the organ for circulating the blood, amount to about sixty in a minute; but, during their torpid state, do not exceed the same number in the space of an hour; so that the pulsations of the heart, during the three months of winter that they become insensible, amount to no more than the usual number of thirty-six hours in their active state, and their demand for nourishment is probably diminished in the same proportion.
The other animals, that are not rendered torpid by the cold, yet feel very sensibly its effects, which are a deficiency of food and heat; to obviate these pressing evils, the wild quadrupeds of prey by which this island is inhabited, such as the fox, the weasel, the polecat, and others, rendered bold