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ther two rings; but, according to Kater's report, he saw in 1825 not only the two rings, but the outer ring appeared to be divided into two parts by a strong black line, as at fig. 1, and each part to be subdivided into at least two others by fainter black lines, as at fig. 3. A drawing made by another person of this appearance is given at fig. 2. Great doubt has been expressed relative to the fact of the outer ring being thus subdivided. Continued observation was interrupted at the time by the ring disappearing, in consequence of the Earth. coming into its plane: but the subject will probably not be lost sight of by those who have the best means for observation; and, as the ring is now again expanding to view, the opportunity is afforded for deciding whether the effects noticed by Kater arose from an optical delusion, or corresponded with the phenomena of the belts and zones, which cross the bodies of Jupiter and Saturn. Some astronomers have imagined these rings to be a vast assemblage of satellites. They certainly serve the purpose of many thousand satellites, and, together with the seven acknowledged moons, probably make up the deficiency in the solar rays coming from such an extreme distance.

Seven satellites, or moons, have been discovered to pass in orbits round the planet Saturn. Two of these moons, the nearest to the body of the planet, were discovered by Herschel with his great telescope. The most distant of the satellites is much the largest, and the next is a very conspicuous object with a good telescope; the next three are very minute, and cannot be seen without very good telescopes, while the two innermost have never been seen, except with the most powerful and finished instruments made by man. The

ring and satellites of Saturn serve, in fact, to test the light and distinctness of telescopes.

But, however useful these moons and rings may be to the inhabitants of Saturn, they do not, as the moons of Jupiter, answer any directly useful purpose to the inhabitants of the Earth. Their great distance, and the consequent difficulty of seeing them, render them nearly useless, with reference to the longitude. We leave them, therefore, to act their part as Providence has appointed them, though we cannot but gaze upon and think of them with astonishment, and admiration of the all-surrounding power of the Almighty.

One Moon on us reflects its cheerful light;

There, seven attendants brighten up the night;
Here, the blue firmament bedecked with stars;
There, over head a lucid arch appears.

The ring revolves round the planet in about 10 hours and 32 minutes, and in the same plane; which rapidity of revolution gives it a centrifugal force, which keeps it at its due distance in equilibrium.

URANUS.

From Earth, how large, how strong, the Sun's bright ball !
But seen from thence, how languid and how small!
When the keen north, with all its fury blows,
Congeals the floods, and forms the fleecy snows,
'Tis heat intense to what can there be known;
Warmer our poles than is its burning zone:
Who there inhabit, must have other powers,
Juices, and veins, and sense, and life, than ours.

This is the last and remotest planet in the solar system, as at present known. It is distant from the Sun the enormous quantity of 1800 millions of miles,

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being about 19 times further from the Sun than the Earth is; he is about 35,112 miles in diameter, and revolves round the Sun in about 83 years and 150 days: this is the year of Uranus. His summer halfyear, therefore, is upwards of 41 of our years, and his winter half-year equally long. The surface of the Sun appears from this planet not aboveth of that which it appears to the Earth; the light and heat received by Uranus are, therefore, smaller in the same proportion. Hence it is quite impossible that any such a fluid as water could exist in that planet, for all would be frozen; and no inhabitants, constituted as the inhabitants of the Earth are, could exist on its surface. Its light from the Sun has been estimated at about the quantity which would be afforded by 240 of our full moons.

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excellent telescope constructed by himself, which magnified several hundred times. The first circumstance which led him to think that it was a planet, and not a fixed star, was that, although it appeared like a star of the seventh magnitude to the naked eye, yet it appeared as one of the first magnitude when seen through his telescope. Now one consequence of the immeasurable distances of the fixed stars is, that they do not appear larger when viewed through a telescope than when seen with the eye, the only difference being an increase of brilliancy. From the circumstance, therefore, of its increased magnitude, Herschel concluded that this celestial body was not a fixed star, but a comet; subsequently, however, he arrived at the conclusion, that it was a planet moving round the Sun: to this conclusion he was led by observing its continued proximity to the ecliptic, and its motion among the fixed stars from west to east.

This planet subtends an angle of about 4′′, which never appears to vary, owing to the comparative smallness of our orbit. Its disk appears uniformly illuminated, and without rings, belts, or spots. Its bulk is however 80 times that of the Earth, and is supposed to be not quite so dense as water. The orbit of this planet is inclined at an angle of 46′ to the ecliptic.

It is just possible to see this planet with the naked éye on a fine clear evening, when the Moon is absent, but it has rarely been noticed without the telescope, when it appears of a blueish white colour. It is said to have been seen before, but to have been regarded as a fixed star. Tycho Brahé, we are told, set it down in his catalogue of the fixed stars; as also did Professor Meyer, of Gottingen, in the year 1756.

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