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were put together, they are not equal to a ten thousandth part of the sun; or rather, it would require ten thousand such masses to make up the bulk of the sun.
258. Besides the seven planets, and their eighteen moons, there are four very small bodies called Asteroids, which move round the sun between the orbits of Mars and Jupiter, called Ceres, Pallas, Juno, and Vesta, all of them late discoveries.
259. There are also a multitude of bodies, some as large as the earth, called Comets, which exhibit very peculiar phenomena of the sun. The planets move round him in orbits nearly circular, but comets almost touch the sun in one part of their orbit, and then stretch out into space thousands of millions of miles.
THE COMET OF 1680,
Hast thou ne'er seen the comet's flaming light?
260. The twinkling stars, of which we see so many every clear evening, do not belong to our solar system ; but are themselves so many Suns to other systems like ours.
Each star is supposed to be the centre of its own system; and to have planets, moons, and comets moving round it at immense distances, like those of our solar system!
Bright legions swarm unseen, and sing, unheard
YOUNG. 261. They are called fixed stars, because they never appear to move; and are so distant, that although the orbit of the earth is twice 93 millions, or 186 millions of miles across; and we are consequently 186 millions of miles nearer to some stars at one time than we are at another, yet the stars always appear in the same place.
Oh nature ! all-sufficient ! over all!
262. The distance of the nearest of the fixed stars cannot be less than 32 billions of miles; and all of them are doubtless as far distant from each other.
They appear to fill infinite space in shoals or vast
system of stars; and our sun is supposed to be one of
YOUNG. 263. The stars as seen through a telescope, are infinite in number, more than 100,000 have been reduced to a catalogue; but with the naked eye, not more than 6 or 800 stars on the clearest night can be seen ;-SO deceptive is the appearance when viewed hastily.
264. The ancients, in order to find and describe the stars, classed them into figures of men and beasts, called Constellations, and there were fifty of these. The moderns have added twenty-four others; so that the celestial globe, in which the stars are accurately laid down as in the heavens, is covered with the figures of these imaginary constellations.
265. In the Zodiac, or part of the heavens where the sun appears to move, there were twelve of these constellations : as, Aries, the Ram
Aquarius, the Water Bearer
Obs. 1.- These constellations were of Egyptian contrivance; and the characters (which it is needful to learn) are Egyptian bieroglyphics, or rude paintings of the things represented, or some known emblem of the things.
2. The signs of the Zodiac, in which the earth and planets move, may also be recollected by means of the following lines:
The ram, the bull, the heav'nly twins,
The virgin and the scales ;
And fish with glittering tails. 266. The most showy of the constellations is Orion, distinguished by his belt of *# in a row; beneath
these is Sirius, the brightest of the stars; and above, to the right, are the red star of the bull, and the Pleiades or Ševen Stars; and to the left, two bright stars, Castor and Pollux.
These bright constellations are always visible on a winter's evening
Obs.-T'he student of nature, who takes an evening's walk to admire the magnificence and the glory of the starry heavens, and desires to profit by bis observations, should learn to class the heavens into particular divisions : and to fix on certain points, as landmarks, to direct his attention.
By knowing the part of the heavens in which the sun rises, he is able to determine the eastern side ; by attending to its situation at noon, be ascertains the south ; and by voticing the place of its setting, he determines the western side of the borizon. He need not be told that the north is opposite to the south.
The moment, then, in which he casts his eyes on the spark. liog expanse of heaven, he is supposed to be sensible of the bearings of the cardınal points, north, south, east and west.
The next principle to be recognised is, that he sees above bis horizon,* one balf of the whole heavens; that is to say, one half of the heavens are always visible, or above the hori. 200, and the other half is below the horizon. He must not expect, therefore, to see all the constellations and planets at once ; but only that half which at the time of observation, is above the horizon.
For the sake of precision and acurate reference, astronomers have supposed the 360 degrees, into which geographers divide the surface of the earth, to be extended to the heavens; so that the whole circumference of the horizon of the heavens is supposed to be 360 degrees, or proportional parts ; half is 180 degrees, and a quarter is 90 degrees. And as we see one half of the heavens above the horizon, it is of course 180 degrees from one side of the horizon, in a line passing over our heads, to the side directly opposite; and of course from the point over our heads, called the zenith, it is 90 degrees to the horizop on every side.
Remember, then, that the whole heavens are 360 degrees, or proportional parts round, and that from the point directly over head, it is always 90 of these degrees down to the horizon.
An observer of the heavens will discover the progression of the whole, from east to west, by a quarter of an bour's attention. Let him bring a star, in any part between the zenith and the southern part of the horizon, into apparent contact with the end of a house, steeple, or other fixed object, and he will in a few minutes perceive the motion of that star, and of the whole heavens, from east to west.
It may be proper for the student now to consider, that this general motion of the whole teavens is merely apparent; and is occasioned by the rotation of the earth on its axis in a con
* The horizon is the line all around where the sky and the earth seem to meet. The senith is the point directly over head, 90 degrees from the horison.