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fact. Very many nebulæ have been removed from their old places, and must hereafter figure among the clusters, while we are informed that many yet remain, even of the old nebulæ, which defy the power of the monster telescope.

The most remarkable object which has been resolved by Lord Rosse, is the great nebula in Orion, one of the most extraordinary objects in the heavens. Its size is enormous, and its figure very extraordinary. In certain parts adjoining the nebula the heavens are jet black, either from contrast or by the vacuity of these regions. Two immense spurs of light are seen to project from the principal mass of the nebula, and to extend to a most extraordinary distance. This will be better understood, by remembering that at the distance at which this nebula is removed from us, the entire diameter of the earth's orbit, 190 millions of miles, is an invisable point, less than one second, while this nebula extends to many thousands of times this distance, and more probably to many millions of times. Several stars have been found, and are visible on the nebula, but have hitherto been regarded as being between the eye of the observer and this remote object. Sir William Herschel was unable to resolve this mysterious body, and yet the nebula gave indications of being of the resolvable kind by its irregular and curdled appearance under high powers. Several years since Dr. J. Lamont, of Munich, after a rigid scrutiny, of this nebula with his great Refractor, pronounced a portion of it to be composed of minute stellar points, and predicted its final perfect resolution into stars by greater power. This prediction has been fully verified, for Lord Rosse's great Reflector has solved the mystery, and filled this extraordinary object with the "jewelry of stars."

But the question recurs, what have the defenders of the nebular theory lost, or its enemies gained by this interesting discovery? We are all liable to reach conclusions too hastily, and to join issue on false points. If the nebular theory depended for its existance upon the irresolvability of the nebula in Orion, then indeed has the theory been entirely exploded. But this is not the fact. No one has asserted that the great nebula in Orion was nebulous matter, and if it were not, then none existed. Such an issue would have been a false one, had it been made. The theory has neither lost nor gained by the discoveries

thus far made; what time may develope it is impossible to say. In case certain data can be obtained, which appear to be accessible, then indeed may we demonstrate its truth or false hood, by mathematical investigation. Until then, the safer plan is neither to adopt nor reject, but investigate until absolute truth shall reward our long continued labor, and reveal the mystery of the organization of that stupendous system, of which our humble planet forms an insignificant part.-Smith's Astronomy.

The sun is the center of the solar system, around which all other planets belonging to our universe revolve. The names of all the primary planets that have been discovered that constitute the solar system, are the Sun, Mercury, Venus, the Earth, Mars, Jupiter, Saturn, Herschel, Uranus, Neptune, and twenty-three asteroids, or small planets. The approximate distance each of the large planets travel in making one revolution around the sun is about as follows:

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Very little is known of the physical nature of comets. They are thought by some astronomers to be about as dense as smoke. They are bodies that revolve around the sun in very elongated orbits, and some astronomers think that the greater number visit our system but once, and then fly off in nearly straight lines, and go to revolve around other suns in the far-off distant heavens. The length of the tail of a comet, as measured by astronomers, seem almost incredible. Comet of 1680, length of the tail..................... ..123,000,000 miles. 35,000,000 48,000,000

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The sun is 1,384,472 times as large as the earth; Jupiter is 1,280 times larger than the earth, and Saturn 1,000 times.

DIRECTIONS FOR FINDING THE NORTH STAR, AT ANY TIME.

Every pupil should be instructed in the manner of pointing out the North Star at any time of the night. If they are enabled to do this at any time, it will assist them in making other important observations, as well as being of use on many occasions which occur in the life of every man. Many persons have been lost in a prairie or other unfrequented places, when if they had been able to have told the points of the compass they could have extricated themselves from their lost situation. This may be done in a very easy manner. There is hardly a child of ten years of age who cannot at any time of night point out the stars in the Great Bear which form what is called the Great Dipper. Now if an imaginary line be drawn through the two stars which form the front edge of the Dipper, from the bottom towards the top, and continued about 20 degrees, it will pass very near the North Star-so near that it cannot be mistaken, there being no other stars of that magnitude near it. It should be borne in mind that this rule holds good in whatever position the Dipper may be at the time.— Smith's Illustrated Astronomy.

ECLIPSES.

Eclipses are among the most interesting phenomena presented to us by the heavenly bodies. In all ages, when an eclipse has taken place, it has excited the profound attention of the learned, and the fears and superstitions of the ignorant. The causes of eclipses before the seventeenth century were known only to a few, and they generally took advantage of this knowledge to impose upon the credulity of the ignorant by pretending that they were inspired by the Gods. Among the ancient nations, the Chaldeans were the foremost in their observations of the phenomena of the heavens; perhaps this was owing in some measure to their occupation; they being shepherds were obliged to watch their flocks by night to protect them from the wild beasts which were at that time numerous. Men under such circumstances would naturally be led to watch closely the movements of the heavenly bodies, and more especially so, for in the earlier periods of the world they had no correct mode of reckoning time in order to determine the seasons or the proper seed time and harvest.

Eclipses attracted the particular attention of the Chaldeans,

and by a series of observations extended through several centuries, they discovered a very important fact relating to eclipses, although they did not understand the cause.

By comparing the records which had been made for a great length of time, they found that a certain period of time elapsed between eclipses of the same kind and magnitude; that is, if 18 years, 11 days, 7 hours and 43 minutes, were added to the time of the happening of any eclipse, it would show the time of the return of the same eclipse; the only differences would be that it would not happen at the same time in the day and it would be a little greater or less than the previous eclipsethus they were able to predict eclipses with sufficient accuracy to answer their designs upon the ignorant without understanding the laws by which these periodical returns were produced.

To explain this briefly, it must be remembered that the moon's orbit makes an angle with the plane of the earth's orbit of 5 deg.; these two points where the moon's orbit cuts the plane of the earth's orbit, are called nodes. Now we will suppose that on any day at noon it is new moon, and the moon is just 16 deg. from her descending node, the shadow of the moon would just touch the earth at the north pole; in 223 lunations, or 18 years, 11 days, 7 hours, 43 minutes thereafter, the moon would come nearly to the same position as it was at the beginning, consequently there would be another small eclipse of the sun, and at the expiration af every 223 lunations it would return, and at each return the moon's shadow would pass across the earth a little more to the south until the eclipse had appeared about 77 times, when it would pass off at the south pole, occupying a period of 1,388 years: The same period would not commence again until the expiration of 12,492 years. Each eclipse which takes place during any year, belongs to a separate and similar period. Those periods of eclipses which come in at the moon's ascending node, first come on to the earth at the south pole, and at each return the moon's shadow passes across the earth more to the north, and after appearing about 77 times, they finally leave the earth at the north pole.-Smith's Astronomy.

IMMENSITY OF SPACE.

Great is the immensity of space. Light travels at the rate of one hundred and ninety-two thousand miles per second and yet at this great speed it would take it over thirty million years to come from some of the far off nebulas to the earth. Some ideas of the immensity of space may be gathered by the calculation of the distance that light would travel in thirty millions of years, and then supposing that the distance ascertained by the calculation, was to the remaining distance as one drop of water is to the ocean. In all probability the most powerful telescope has only brought to view a small portion of creation.

The nearest fixed stars, according to the best astronomical calculation, 20,000,000,000,000 of miles from the earth. To assist the mind of the reader to get some idea of the immensity of this distance, I have taken the pains to make the following calculation: Suppose that when the Lord past sentence upon Cain for killing his brother, that he had banished him to the nearest fixed star, and had caused a whirlwind or some other power to have taken him at the rate of one thousand miles an hour day and night from that time till now, counting the time past six thousand years, at 360 days travel to the year, he would have traveled at the end of the six thousand years only one 3.80th part of the distance, and at the same rate of speed at the end of two million years from this time he would not reach his destination, but would yet be one trillion three hundred and eighty-two billion four hundred million miles from his future home, or place of banishment. So you see that after two million and six thousand years travel at the enormous speed of one thousand miles an hour, leaves a distance yet untraveled equal to about fifty-five miilion times the distance of Cook's voyage around the earth.

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