" The northern parts of Spain, accoi ding to Strabo, (lib. iii.) are but ill inhabited, because of the great cold." These extracts afford the most satisfactory evidence, that the climate of Europe is much milder than it was in ancient times. The difference is undoubtedly owing to the partial clearing of the woods, and the land being better cultivated now than formerly ; so that the super fluous water, which at that time was carried off in a great measure by evaporation, is conveyed away by drains and canals.
The winter cold of the northern parts of Europe is still more than sufficient to freeze mercury. The conge lation of this metal by natural cold, was first observed at Krasnojark, in lat. 56° long. 93° cast. Mercury is said to have been sometimes frozen at Quebec, in lat. 47°.
The following narrative, written by Captain Middle ton, F. R. S. contains so minute a description of the effects of natural cold during winter at Churchill's river, in Hudson's Bay, and is so applicable to the general effects of cold in other places, that we shall make no apology for giving it in his own words.
" The lakes and standing waters, which are not above 10 or 12 feet deep, are frozen to the ground in winter, and the fishes therein all perish.
Yet in rivers near the sea, and lakes of a greater depth than 10 or 12 feet, fishes are caught all the winter, by cutting holes through the ice down to the water, and therein putting lines and hooks. But if they are to be taken with nets, they cut several holes in a straight line the length of the net, and pass the net, with a stick fast ened to the head-line, from hole to hole, till it reaches the utmost extent ; and what fishes come to these holes for air, are thereby entangled in the net ; and these fishes, as soon as brought into the open air, are instantaneously frozen as stiff as stock-fish. The seamen likewise freshen their salt provisions, by cutting a large hole through the ice in the stream or tide of the river, which they do at the beginning of winter, and keep it open all that season ; in this hole they put their salt meat, and the minute it is immersed under water, it becomes pliable and soft, though before its immersion it was hard frozen.
Beef, pork, mutton, and venison, that are killed at the beginning of winter, are preserved by the frost for six or seven months, entirely free from putrefaction, and prove telerably good eating. Likewise geese, partridges, and
other fowl, that arc killed at the sante time, and kept with their feathers on and guts in, require no other pre servative but the frost to make them good wholesome eating, as long as the winter continues. All kinds of fish are preserved in the like manner.
In large lakes and rivers, the ice is sometimes broken by imprisoned vapours ; and the rocks, trees, joists, and rafters of our buildings, are burst with a noise not less terrible than the firing of a great many guns together. The rocks which arc split by the frost, are heaved up in great heaps, leaving large cavities behind ; which I take to be caused by imprisoned watery vapours, that require more room when frozen, than they occupy in their fluid -,tate. Neither do I think it unaccountable, that the frost should be able to tear up rocks and trees, and split the beams of our houses, when I consider the great force And elasticity thereof. If beer or water is left in mugs, cans, or bottles, nay in copper pots, though they were put by our bedsides, in a severe night they are surely plit to pieces before morning, not being able to withstand the expansive force of the Inclosed ice.
The air is filled with innumerable particles of ice, ve ry sharp and angular, and plainly perceptible to the na ked eye. I have several times, this winter, tried to make, observations of some celestial bodies, particularly the immersions of the satellites of Jupiter, with reflecting and refracting telescopes ; but the metals and glasses, by that time I could fix them to the object, were covered a quarter of an inch thick with ice, and thereby the object rendered indistinct, so that it is not without great difficul ties that observations can be taken.
Bottles of strong beer, brandy, strong brine, spirits of wine, set out in the open air for three or four hours, freeze to solid ice. I have tried to get the sun's refrac tion here to every degree above the horizon, with Elton's quadrant, but to no purpose, for the spirits froze almost. as soon as brought into open air.