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But minute and care

Indistinct glances at the stars, often leave the impression that several thousands may be seen at once. ful surveys will correct this error. The Fixed Stars are easily distinguished from the steady light of the planets, by their scintillation or twinkling.

It is highly probable, that grouping the STARS into constellations, was done by the ancients, partly for the purpose of perpetuating important events in sacred and profane history, and partly to subserve their convenience of classification. Some of these constellations are very ancient, as their names are found in the most ancient writings extant. Perhaps the Ship and the Raven are of Hebrew origin; while Hercules, Andromeda and others, undoubtedly originated with the Greeks.

Patient surveys of the number and positions of the Fixed Stars, have been made by Hipparchus, Ptolemy, Tycho Brahe, Hevelius, and Flamstead, affording interesting opportunities of comparing ancient and modern observations.

The ancient constellations amounted to but 48. Modern catalogues have arisen to between 90 and 100. I shall use a list containing 93 constellations, where the number of stars in and near each, is given according to Flamstead. Seven or eight hundred stars are inserted, too small to be seen without a telescope, leaving from 2000 to 2200 visible to the naked eye. The stars visible without a telescope, are divided into six classes. The largest, are called stars of the 1st magnitude; the least, stars of the 6th magnitude. There are about 17 of the 1st magnitude, 50 of the 2nd magnitude,

Why are we liable to misjudge respecting their number? How may they be distinguished from planets?

Why have the stars been grouped? To what nations are some of them obviously to be traced? Who have minutely sur veyed them? How many ancient constellations ?-modern ones? Into how many classes are the stars divided?

150 of the 3rd magnitude, and the remainder are of the 4th, 5th and 6th magnitudes.

A LIST OF THE CONSTELLATIONS.

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The distances of the fixed stars deserve consideration; for though the exact distance of Sirius, supposed to be the nearest, cannot be given, it can be proved that it must be more than 200 thousand times as distant as the Sun.

That the fixed stars are very distant, is obvious from these facts. Seen through a telescope of 200 magnifying power, they seem less than to the naked eye. Increase the magnifying power of the glass, they are still but luminous points, while the planets disclose broad discs, which can be measured; and satellites before invisible. Again, the Earth's place the 23rd of September, is the whole diameter of its orbit distant from where it was the 20th of March, but the nearest fixed star is too remote to have that 190 millions of miles, make any apparent change in its direction, and such change would be perceptible, if the star were not more than 200 thousand times the distance. of the Sun.

How many constellations in the southern hemisphere? What star is supposed to be the nearest? How distant must it be? What proof can you give, that the stars are 200 thousand times more distant than the Sun ?

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