one and the same point, a little southeast of the zenith. Follow ing the arch of the sky, they ran along with immense velocity, describing, in some instances, an arc of 30 or 40° in a few

seconds. On more attentive inspection it was seen, that the meteors exhibited three distinct varieties; the first, consisting of phosphoric lines, apparently described by a point; the second, of large fire-balls, that at intervals darted along the sky, leaving luminous trains, which occasionally remained in view for a number of minutes, and, in some cases, for half an hour or more; the third, of undefined luminous bodies, which remained nearly stationary in the heavens for a long time.

Those of the first variety were the most numerous, and resembled a shower of fiery snow driven with inconceivable velocity to the north of west. The second kind appeared more like falling stars-a spectacle which was contemplated by the more unenlightened beholders with great amazement and terror. The trains which they left were commonly white, but sometimes were tinged with various prismatic colors, of great beauty.

299. These fire-balls were occasionally of enormous size. Dr. Smith, of North Carolina, describes one which appeared larger than the full moon rising. "I was," says he, startled by the

223 What remarkable circumstance attended this phenomenon? 299 What said of the fireballs seen? Of their size?

Variety of meteors!

splendid light in which the surrounding scene was exhibited, rendering even small objects quite visible."

The same ball, or a similar one, seen at New Haven, passed off in a northwest direction, and exploded a little northward of the star Capella, leaving, just behind the place of explosion, a train of peculiar beauty. The line of direction was at first nearly straight; but it soon began to contract in length, to dilate in breadth, and to assume the figure of a serpent SCROLLING itself up, until it appeared like a luminous cloud of vapor, floating gracefully in the air, where it remained in full view for several minutes.

If this body were at the distance of 110 miles from the observer, it must have had a diameter of one mile; if at the distance of 11 miles, its diameter was 528 feet; and if only one mile

off, it must have been 48 feet in diameter. These considerations leave no doubt that many of the meteors were bodies of large size.

300. Of the third variety of meteors, the following are remarkable examples :-At Poland, Ohio, a luminous body was distinctly visible in the northeast for more than an hour. It was very brilliant, in the form of a pruning-hook, and apparently twenty feet long, and eighteen inches broad. It gradually settled toward the horizon, until it disappeared.

At Niagara Falls, a large luminous body, shaped like a square table, was seen near the zenith, remaining for some time almost stationary, emitting large streams of light.

301. The point from which the meteors seemed to emanate, was observed, by those who fixed its position among the stars, to be in constellation Leo; and, according to their concurrent testimony, this RADIANT POINT was stationary among the stars, during the whole period of observation; that is, it did not move along with the earth, in its diurnal revolution eastward, but accompanied the stars in their apparent progress westward.

A remarkable change of weather, from warm to cold, accompanied the meteoric shower, or immediately followed it. In all parts of the United States, this change was remarkable for its suddenness and intensity. In many places, the day preceding had been unusually warm for the season, but, before the next morning, a severe frost ensued, unparalleled for the time of year.

302. In attempting to explain these mysterious phenomena, it is argued, in the first place, that the meteors had their origin beyond the limits of our atmosphere; that they of course did not belong to this earth, but to the regions of space exterior to it

800. What other variety of meteors described? Where? hey seemed to emanate? What change of weather folle ved? as to the distance from which those meteors came dist ince?

The reason on which the conclusion is founded is this:-All bodies near the eart! including the atmosphere itself, have a common motion with the earth around its axis from west to east; but the radiant point, that indicated the source from which the meteors emanated, followed the course of the stars from east to west; therefore, it was independent of the earth's rotation, and consequently, at a great distance from it, and beyond the limits of the atmosphere. The height of the uieteoric cloud, or radiant point, above the earth's surface, was, according to the mean average of Professor Olmsted's observations, not less than 2238 miles.

303. That the meteors were constituted of very light, combustible materials, seems to be evident, from their exhibiting the actual phenomena of combustion, they being consumed, or converted into smoke, with intense light; and the extreme tenuity of the substance composing them is inferred from the fact that they were stopped by the resistance of the air. Had their quantity of matter been considerable, with so prodigious a velocity, they would have had sufficient momentum to dash them upon the earth; where the most disastrous consequences might have followed.

The momentum of even light bodies of such size, and in such numbers, traversing the atmosphere with such astonishing velocity, must have produced extensive derangements in the atmospheric equilibrium. Cold air from the upper regions would be brought down to the earth; the portions of air incumbent over districts of country remote from each other, being mutually displaced, would exchange places, the air of the warm latitudes be transferred to colder, and that of cold latitudes to warmer regions.

304. Various hypotheses have been proposed to account for this wonderful phenomena. The agent which most readily suggests itself in this, and in many other unexplained natural appearances, is electricity. But no known properties of electricity are adequate to account for the production of the meteors, for their motions, or for the trains which they, in many instances, left behind them. Others, again, have referred their proximate cause to magnetism. and to phosphureted hydrogen; both of which, however, seem to be utterly insufficient, so far as their properties are known, to account for so unusual a phenomenon.

305. Professor Olmsted, of Yale College, who has taken much pains to collect facts, and to establish a permanent theory for the periodical recurrence of such phenomena, came to the conclusion, that

The meteors of November 13th, 1833, emanated from a nebulous body, which was then pursuing its way along with the earth around the sun; that this body continues to revolve around the sun, in an elliptical orbit but little inclined to the plane of the ecliptic, anu having its aphelion near the orbit of the earth; and finally, that

803. Supposed composition of these meteors? Why? 304. Hypotheses for explain ng phenomenon? Are they satisfactory? 805. Professor Olinsted's couclusion!

E

the body has a period of nearly six months, and that its perihelion is a little below the orbit of Mercury*

This theory at least accommodates itself to the remarkable fact, that almost all the phenomena of this description, which are known to have happened, have occurred in the two opposite months of April and November. A similar exhibition of meteors to that of November, 1833, was observed on the same day of the week, April 20th, 1803, at Richmond, Virginia; Stockbridge, Massachusetts; and at Halifax, in British America. Another was witnessed in the autumn of 1818, in the North Sea, when, in the language of the observers, "all the surrounding atmosphere was enveloped in one expansive sea of fire, exhibiting the appearance of another Moscow, in flames."

After the first edition of this work went to press, the author was politely furnished, by Professor Olmsted, with the following communication.

"I am happy to hear that you propose to stereotype your 'Geography of the Heavens. it has done much, I believe, to diffuse a popular knowledge of astronomy, and I am pleased that your efforts are rewarded by an extended patronage.

"Were I now to express my views on the subject (Meteoric Showers) in as condensed a form as possible, I should state them in some such terms as the following: The meteoric showers which have occurred for several years past on or about the 18th of November, are characterized by four peculiarities, which distinguish them from ordinary shooting stars. First, they are far more numerous than common, and are larger and brighter. Secondly, they are in much greater proportion than usual, accompanied by luminous trains. Thirdly, they mostly appear to radiate from a common center; that is, were their paths in the heavens traced backward, they would meet in the same part of the heavens: this point has for three years past, at least, been situated in the constellation Leo. Fourthly, the greatest display is everywhere at nearly the same time of night, namely, from three to four o'clock—a time about half-way from midnight to sunrise. The meteors are inferred to consist of combustible matter, because they are seen to take fire and burn in the atmosphere. They are known to be very light, because, although they fall toward the earth with immense velocity, few, if any, ever reach the earth, but are arrested by the air, like a wad fired from a piece of artillery. Some of them are inferred to be bodies of comparatively great size, amounting in diameter to several hundred feet, at least, because they are seen under so large an angle, while they are at a great distance from the spectator. Innumerable small bodies, thus consisting of extremely light, thin, combustible matter, existing together in space far beyond the limits of the atmosphere, are believed to compose a body of immense extent, which has been called the nebulous body.' Only the skirts or extreme portions of this are brought down to the earth, while the entire extent occupies many thousands, and perhaps several millions of miles. This nebulous body is inferred to have a revolution around the sun, as well as the earth, and to come very near to the latter about the 18th of November each year. This annual meeting; every year, for several years in succession, could not take place unless the periodic time of the nebulous body is either nearly a year, or half a year. Various reasons have induced the belief that half a year is the true period; but this point is con sidered somewhat doubtful. The zodiacal light, a faint light that appears at different seascos of the year, either immediately preceding the morning or following the evening twiht, ascending from the sun in a triangular form, is, with some degree of probability, thought to be the nebular body itself, although the existence of such a boly, revolving in the solar system, was inferred to be the cause of the meteoric showers, before any connection of it with the zodiacal light was even thought of."

With what remarkable fact doce his theory accord?
Omsted?

Substance of letter from Professor

306. Exactly one year previous to the great phenomenon of 1833, namely, on the 12th of November, 1832, a similar meteoric display was seen near Mocha, on the Red Sea, by Capt. Hammond and crew of the ship Restitution.

While

A gentleman in South Carolina thus describes the effect of the phenomenon of 1833, ipon his ignorant blacks: "I was suddenly awakened by the most distressing cries that ever fell on my ears. Shrieks of horror, and cries of mercy, I could hear from most of the negroes of three plantations, amounting in all to about six or eight hundred. earnestly listening for the cause, I heard a faint noise near the door calling my name; I arose, and taking my sword, stood at the door. At this moment, I heard the same voice still beseeching ine to rise, and saying, O, my God, the world is on fire!' I then opened the door, and it is difficult to say which excited me most-the awfulness of the scene, or the distressed cries of the negroes; upward of one hundred lay prostrate on the ground-some speechless, and some with the bitterest cries, but most with their hands raised, imploring God to save the world and them. The scene was truly awful; fo never did rain fall much thicker, than the meteors fell toward the earth; east, west. north, and south, it was the same!"

306. What similar meteoric shower referred to? Description of that of November 1333, and its fects upon certain persons?