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the stars were indeed falling from heaven. Different names have been applied to them, although the distinction is not very definite. (1) Aerolites are those

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stony masses which fall to the earth. (2) Shooting Stars are those evanescent brilliant points that snd

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seasons. The sun gives to Neptune but ^Vr the light aui heat which we receive.

T' nugh at the extreme of the solar system, 2,650 miiii ns of miles beyond us, the same heavens bend above, the same starry sky is seen by night—the Milky Way is no nearer to the eye, the fixed stars shine no more brightly. The planets, however, are all too near the sun to be seen, except Saturn and Uranus. The Neptunian astronomers, if there be arv, are well situated for observing the orbits of co- • r Is, and for measuring the annual parallax of the stars, since they have an orbit of 5,500 million miles in diameter, and hence the angle must be 30 times as great as that which the terrestrial orbit affords.

Telescopic Features.—On account of the recentness of the discovery of this planet and its immense distance, nothing is known of its rotation or physical features.

Satellites.—Neptune has one moon, at nearly the same distance from it as our own moon is from the earth. The revolution of this about the planet, which is accomplished in about six days, has furnished the materials for calculating the mass of Neptune.

METEOES AND SHOOTING STAES.

Description.—All are familiar with those luminous bodies that flash through our atmosphere as if the stars were indeed falling from heaven. Different names have been applied to them, although the distinction is not very definite. (1) Aerolites are those

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stony masses which fall to the earth. (2) Shooting Stars are those evanescent brilliant points that suddenly dart through the higher regions of the air, leaving a fiery train behind. (3) Meteors are luminous bodies which have a sensible diameter and a spherical form. They frequently pass over a great extent of country, and are seen for some seconds of time. Many leave behind a train of glowing sparks; others explode with reports like the discharge of artillery,—the pieces either continuing their course, or falling to the earth as aerolites. Some meteors, doubtless, after having favored us with a transient illumination, pass on into space; some are vaporized; while others are burned and the ashes and fragments fall to the ground.

Aerolites.—The fall of aerolites is frequently mentioned and well authenticated. Chinese records tell of one as long ago as in 616 B. c, which, in its fall, broke several chariots and killed ten men. A block of stone, equal to a full wagon-load, fell in the Hellespont, B. c 465. By the ancients, these stones were held in great repute. The Emperor Jehangire, it is related, had a sword forged from a mass of meteoric iron which fell in the Punjab in 1620. In 1795, a mass was seen, by a ploughman, to descend toward the earth at a spot not far from where he was standing. It threw up the soil on every side, and penetrated some distance into the solid rock beneath. In 1807, a shower of stones, one weighing 200 lbs., fell at Weston, Connecticut. These aerolites are sometimes seen to plunge downward into the earth, and are found while yet glowing. A mass thus fell in South America, which was estimated to weigh fifteen tons. When first discovered, it was so hot as to prevent all approach. Upon its cooling, many efforts were made, by some travellers who were present, to detach specimens, but its hardness was too great for any tools which they possessed. There is a mass of meteoric iron in Yale College cabinet, weighing 1,635 lbs.

Aerolites consist of elements which are familiar. The analysis of these stellar masses gives us names as commonplace as if they had known a far less romantic origin—oxygen, sulphur, phosphorus, iron, tin, copper: in all, nineteen elements have been found. This fact is interesting as revealing something of the chemistry of the region of space, concerning which we otherwise know nothing. The compounds, however, are very peculiar, so as to distinguish an aerolite from any terrestrial substance. For example, meteoric iron, a prominent constituent of aerolites, is an alloy that has never been found in terrestrial minerals.

Meteors.—The records of meteors are still more wonderful. It is related that at Crema, Italy, one day in the 15th century, the sky at noonday became dark,—a cloud of appalling blackness overspreading the heavens. Upon this cloud appeared the semblance of a great peacock of fire flying over the town. This suddenly changed to a huge pyramid, that rapidly traversed the sky. Thence arose awful lightnings and thunderings, amid which there fell

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