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its general rotuudity. Chimboraço, one of the Andes, rears its lofiy head four miles high, yet this is but the two thousandth part of the carth's diameter.
Obs.--- Mount Blanc is not three miles high, the Peake of Teneriffe but two miles and a half; and Mouot Elba pot two mniles. Our Snowdon is not three quarters of a mile ; and but a grain of sand compared to the whole earth.
239. The mines, therefore, may be compared to the sting of a bee in the body of an elephant; and the mountains to the inequalities in the rind of an orange ; yet, vast as is the earth, the sun, which enlightens and warms it, is one million times greater; or, in other words, one Inillion earths united in one mass, would only be the size of the sun.
240. The land consists of two continents ; the old continent of Europe, Asia, and Africa, and the lately-discovered continent of America.
There are also many thousand islands sur. rounded by the sea; iany of them, as Great Britain, anciently united to the continent, and others, the tops of marine mountains peeping out of the sea, the bases of which are at the bottoin of the ocean.
241. When a point of land juts out into the cea, it is called a Cape or Promontory; as the Cape of Good Hope.
When two masses of land are joined toge. ther by a narrow slip, it is called an Isthmus; as the Isthmus of Suez, and the Isthmus of Panama.
A Peninsula is a tract of land almost suf
rounded by water: Spain and Portugal are a peninsula.
242. The waters are usually divided into four Oceans; the Great or Pacific Ocean, ten thousand miles across"; the Atlantic Ocean, three thousand miles across; the lodian and Southern Ocean; and the Northern Ocean.
Seas are detached pieces of water; as the Mediterranean and the Baltic.
Gulfs and Bays are parts of the sca that indent into the land.
And Straits are narrow passes joining one sea or ocean to another.
243. The vast Sun, to which we are under such sensible obligations, for light, heat, life, and vegetation ; and without whose genial influence all the Earth would become a dark, solid mass of ice, is 900,000 miles in diameter; and the earth is 95 millions of miles distant from it.
244. The Sun is the centre of a vast system of planets, or globes, like the earth; all of which move round bis body at immense distances, in periods which include the various seasons to each, and are therefore a year to each.
Obs. They are all pressed to each other's centre; hut the action of their fluid parts against their solid parts, gives them a tendency to go forward in a straight line; and those two forces so balance each other, that they neu. tralize one another, and, in consequence, the planets are moved round the sun in an orbit which is nearly circular. See 274.
245 The Sun has been commonly considered a globe of pure fire. A number of maculæ, or
dark spots, nay, however, by means of a telescope, be seen on different parts of his surface.
These consist of a nucleus, which is much darker than the rest, and surrounded by a mist or smoke; and they are so changeable as frequently to vary during the time of observation.
Some of the largest of them exceed the bulk of the whole earth, and they are often seen for three months together.
They are supposed to be cavities in the body of the sun ; the nucleus being the bottom of the excavation; and the shady zone surrounding it, the shelving sides of the cavity.
Grent source of day I best Image hore below
Thy system rolla entires from the far bourn
246. As the Sun is one million times larger than the earth, it is evident that the balance of their mutual pressure would not be destroyed, if one million of earths moved round the Sun ; but, at present, we know only of SEVEN such bodies, some nearer and some farther off than the earth, and some greater, and some larger, called Mercury, Venns, Earth, Mars, Jupiter, Saturn, and Herschel.
The Sun revolving on his axis turns,
247. Some of these several globes, so revolving to receive light and hent from the sun, serve as centres to other minor globes called Moons. These satellites accompany the planet
in its tour round the Sun; serving to balance its motions, and to reflect hy night the Sun's light on the planet for the use of the inhabitants,
2-18. The earth has one moon, 2,000 miles in diameter, and a quarter of a million of miles distant from the Earth.
Jupiter, another planet, has four moons.
Saturn seven mouus ; and he is also sur rounded by a large double ring, 30,000 miles distant from his body.
And Herschel has six moons.
349, But if the matter of all these planets and moons 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,
950. Besides the seven planets, and their eighteen moons, there are four very small bodies called Asteroids, which inove round the Sun between the orbits of Mars and Jupiter, called C'eres, Pallas, Juno, and Vesta, all of them late discoveries.
201. There are also a multitude of bodies, some as large as the carth, 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.