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puted to be four or five times as large as the surface of the earth. Sometimes they diminish in magnitude; at others, they disappear all at once before they reach the edge of the disk; at others, new ones are perceived. Thus they present a perpetual irregularity ; their period alone being fixed. Observations of these spots have led to some modifications as to the notions entertained respecting the nature of the body of the Sun. The antients thought it a body of fire; and some a body of gold in a state of fusion. Laplace imagines that the Sun is a mass of fire, subject to immense. eruptions, after the manner of our volcanoes ; on which hypothesis the spots would be vast cavities : from these, torrents of lava are thrown at intervals. Herschel, on the other hand, conceives that the Sun, so far from being fire, is a habitable body, like the earth, surrounded by an atmosphere almost entirely occupied by luminous clouds; and that these occasionally, when disturbed by winds, or other causes, permit the dark nucleus of the Sun to be seen through them, thus forming the solar spots. These spots are almost all comprised in a zone of the Sun's surface, whose breadth, measured on a solar meridian, never goes farther than about 30" from its equator.
Bouquer satisfied himself, by many careful observations, that the light emitted by the Sun comes with more intenseness from the centre than from near the edge of the disk; and as this effect is contrary to that which ought to result from the spherical shape of the luminary, it is manifest that for some reason the Jight near the edges must be in part extinct. This suggests to some a reason for concluding that the Sun is surrounded by an immense atmosphere, which in some measure enfeebles its native light, but more towards the edges, where it is traversed obliquely by the rays : just as our atmosphere diminishes the bril
liancy of the stars, and especially about their rising · and setting.
This solar atmosphere has been proposed again as a mean for explaining that beautiful white light which is seen a little before the Sun's rising, and a little after its setting, and which is called the zodiacal light. Its translucency is such, that very small stars may be seen through it. Laplace, contemplating the Jenticular form of this phenomenon, and its extent, thinks that it may, without hesitation, be ascribed to the solar atmosphere. His explication may be seen in his Système du Mond, liv. iv, chap. 9. It would not consist with our purpose, or our limits, to detail it here,
The Naturalist's Diary,
Now January o'er the northern world
WINTER, 10 an inattentive eye, presents nothing, as it were, but the creation in distress: the orchards are stripped of their golden fruit; and harmony is extinct in the groves, now bending with the snow,
their beauty withered, and their verdure lost.' Yet, when we explore these dreary scenes, the mind is amply gratified in the contemplation of the various phenomena peculiar to this inclement season. Winter, ushered into existence by the howling of storms and the rushing of torrents, manifests, not less than the more pleasing seasons of the year, the wisdom and goodness of the great Creator. Were there no winter, neither the spring, nor summer, nor autumn, would display such a variety of beauties; for the earth itself would lose those rich stores of nourishment and fertility, to which even the winter so copiously-contributes.
The most intense cold is usually felt in the month of January; and the weather is either bright and dry, with frost; or foggy, with much snow :
Thro' the hashed air the whitening show'r descends, At first thin-wav'ring; till, at last, the flakes Fall broad, and wide, and fast, dimming the day With a continual snow. Snow is formed by the freezing of the water in clouds. It differs from the particles of hoar-frost, in being crystallized; for if we examine a flake of snow by a magnifying glass, the whole of it will seem composed of fine shining spicula, or points, diverging like rays from a centre. As the flakes fall down through the atmosphere, they are continually joined by more of these radiated spicula ; and thus increase in bulk, like the drops of rain or hailstones. Snow, although it seems to be soft, is really hard, because it is true ice. It seems soft, because at the first touch of the finger, upon its sharp edges or points, they melt; or, they would pierce the finger like so many lancets. The whiteness of snow is owing to the small particles into which it is divided; for ice, when pounded, will become equally white.
But snow is not to be considered merely as a curi ous and beautiful phenomenon. Besides defending vegetables from the intense cold of the air, and piercing winds, it moistens and pulverizes the soil which has been bound up by the frost; and, as its water has a tendency to putrefaction, it seems, on many accounts, to be admirably fitted to promote vegetation, Another reason of the usefulness of snow, has been suggested by Mr. Parkes. Fur and down afford warm clothing, in consequence of the air they inföld within them; atmospheric air being a non-conductor of heat. • Hence it is that the carpet which covers the earth in winter, is spread out by nature with so light a hand, that it might hold an abundance of atmospheric air within its interstices, to preserve the warmth of those
innumerable tribes of vegetables which it is destined to protect.'.
Ice is composed of a number of needle-like cystals, united to each other; and, the space between these being greater than between the particles of water, this liquid, when frozen, though it is not heavier, yet it occupies more space than before. From this principle of expansion, water-pipes often burst, and hoops fly off from barrels, during an intense frost. To this cause may be attributed the annual diminution of the bulk and height of lofty mountains. The different crevices being filled with water in the summer, this water becomes frozen in the winter; and, by the power of expansion, rolls down vast masses of rock or earth into the neighbouring valleys. By the same operation, the clods of ploughed fields are loosened, and rendered fit for the work of the bus. bandman. ve The inclemency of the season compels the numerous tribes of birds to quit their retreats in search of food. The redbreast 1 (sylvia rubecula), the only bird that confides in man, begins to sing. Thomson's often quoted but beautiful description of his annual visit we cannot suppress :
Half afraid, be first Against the window beats; then, brisk, alights On the warın hearth; then, hopping o'er the floor, Eyes all the smiling family askance, And pecks, and starts, and wonders where he is : Till more familiar grown, the table-crumbs Attract his slender feet 2. About the beginning of the month, larks (alauda
; . This bird is called Tomi Liden, about Bornholm; Peter Ronsmad, in Normandy; and Thomas Gierdet, in Germany.
2 or, fearlessly, lights down
arvensis) congregate, and fly to the warm stubble for shelter; and the nuthatch (sitta europæa) is heard. The shelless snail or slug (limax) makes its appearance, and commences its depredations on garden plants and green wheat: the body of this creature being covered over with a slimy substance, it can endure the cold much better than the shell-snail. The missel-thrush (turdus viscivorus) begins its song, which is very fine, often with the new year, sitting on the summit of a high tree, in blowing showery weather; whence the inhabitants of Hampshire call it the storm-cock. The hedge-sparrow (sylvia modularis), and the thrush (turdus musicus) begin to sing. The titmouse (parus) pulls straw out of the thatch, in search of insects; linnets (fringilla linota), congregate; and rooks (corvus frugilegus) resort to their nest trees.
The house-sparrow (fringilla domestica) chirps ; the bat (vespertilio) appears ; spiders shoot out their webs; and the blackbird (turdus merula) whistles. The fieldfares, red-wings, skylarks, and titlarks, resort to watered meadows for food, and are, in part, supported by the gnats which are on the snow, near the water. The titlark wades up to its belly in pursuit of the pupæ of insects, and runs along upon the floating grass and weeds. The tops of tender turnips and ivy-berries afford food for the graminivorous birds, as the ringdove, &c. .. Amid the leafless thorn, the merry wren",
When icicles hang dripping,
Athwart the shower, and sings upon the wing. The skylark sings? ; earthworms lie out on the 1 The silvia troglodytes braves our severest winters, which it contributes to enliven by its sprightly note. It continues its song till late in the evening, and not unfrequently during a fall of snow.
2 Nothing can be more pleasing than to see the lark warbling upon the wing; raising its note as it soars, until it seems