bodies. The idea is completely inadmissible that they are concretions formed within the limits of the atmosphere. The ingredients that enter into their composition have never been discovered in it, and the air has been analysed at the sea level and on the tops of high mountains. Even supposing that to have been the case, the enormous volume of atmospheric air so charged required to furnish the particles of a mass of several tons, not to say many masses, is, alone, sufficient to refute the notion. They cannot, either, be projectiles from terrestrial volcanoes, because coincident volcanic activity has not been observed, and aërolites descend thousands of miles apart from the nearest volcano, and their substances are discordant with any known volcanic product. Laplace suggested their projection from lunar volcanoes. It has been calculated that a projectile leaving the lunar surface, where there is no atmospheric resistance, with a velocity of 7771 feet in the first second, would be carried beyond the point where the forces of the earth and moon are equal, would be detached, therefore, from the satellite, and come so far within the sphere of the earth's attraction as necessarily to fall to it. But the enormous number of ignited bodies that have been visible, the shooting stars of all ages, and the periodical meteoric showers that have astonished the moderns, render this hypothesis untenable, for the moon, ere this, must have become sensibly impaired, while no trace of an active volcano has yet been discovered on her surface. Olbers was one of the first to prove the possibility of a projectile reaching us from the moon, but at the same time he deemed the event highly improbable, regarding the satellite as a very peaceable neighbour, not capable now of strong explosions from the want of water and an atmosphere. The theory of Chladni will account generally for all the phenomena, be attended with the fewest difficulties, and, with some modifications to meet circumstances not known in his day, it is now widely embraced. He conceived the system to include an immense number of small bodies, either the scattered fragments of a larger mass, or original accumulations of matter, which, circulating round the sun, encounter the earth in its orbit, and are drawn towards it by attraction, become ignited upon entering the atmosphere, in consequence of their velocity, and constitute the shooting stars, aërolites, and meteoric appearances that are observed. Sir Humphry Davy, in a paper which contains his researches on flame, strongly expresses an opinion that the meteorites are solid bodies moving in space, and that the heat produced by the compression of the most rarefied air from the velocity of their motion must be sufficient to ignite their mass so that they are fused on entering the atmosphere. It is estimated that a body moving through our atmosphere with the velocity of one mile in a second, would extricate heat equal to 30,000° of Fahrenheit—a heat more intense than that of the fiercest artificial furnace that ever glowed. The chief modification given to the Chladnian theory has arisen from the observed periodical occurrence of meteoric showers a brilliant and astonishing exhibition to some notices of which we proceed.

The writers of the middle ages report the occurrence of the stars falling from heaven in resplendent showers among the physical appearances of their time. The experience of modern days establishes the substantial truth of such relations, however once rejected as the inventions of men delighting in the marvellous. Conde, in his history of the dominion of the Arabs, states, referring to the month of October in the year 902 of our era, that on the night of the death of King Ibrahim ben Ahmed, an infinite number of falling stars were seen to spread themselves like rain over the heavens from right to left, and this year was afterwards called the year of stars. In some Eastern annals of Cairo, it is related that "In this year (1029 of our era) in the month Redjeb (August) many stars passed, with a great noise, and brilliant light;" and in another place the same document states:the year 599, on Saturday night, in the last Moharrem (1202 of our era, and on the 19th of October), the stars appeared like waves upon the sky, towards the east and west; they

"In

flew about like grasshoppers, and were dispersed from left to right; this lasted till daybreak; the people were alarmed." The researches of the Orientalist, M. Von Hammer, have brought these singular accounts to light. Theophanes, one of the Byzantine historians, records, that in November of the year 472 the sky appeared to be on fire over the city of Constantinople with the coruscations of flying meteors. The chronicles of the West agree with those of the East in reporting such phenomena. A remarkable display was observed on the 4th of April 1095 both in France and England. The stars seemed, says one, "falling like a shower of rain from heaven upon the earth;" and in another case, a bystander, having noted the spot where an aërolite fell, "cast water upon it, which was raised in steam, with a great noise of boiling." The chronicle of Rheims describes the appearance, as if all the stars in heaven were driven, like dust, before the wind. "By the reporte of the common people, in this kynge's time (William Rufus)," says Rastel, "divers great wonders were sene- and therefore the kyng was told by divers of his familiars, that God was not content with his lyvyng, but he was so wilful and proude of minde, that he regarded little their saying." There can be no hesitation now in giving credence to such narrations as these, since similar facts have passed under the notice of the present generation.

The first grand phenomenon of a meteoric shower which attracted attention in modern times was witnessed by the Moravian Missionaries at their settlements in Greenland. For several hours the hemisphere presented a magnificent and astonishing spectacle, that of fiery particles, thick as hail, crowding the concave of the sky, as though some magazine

of combustion in celestial space was discharging its contents towards the earth. This was observed over a wide extent of territory. Humboldt, then travelling in South America, accompanied by M. Bonpland, thus speaks of it :"Towards the morning of the 13th November, 1799, we witnessed a most extraordinary scene of shooting meteors. Thousands of bodies and falling stars succeeded each other during four hours. Their direction was very regular from north to south. From the beginning of the phenomenon there was not a space in the firmament equal in extent to three diameters of the moon which was not filled every instant with bodies or falling stars. All the meteors left luminous traces or phosphorescent bands behind them, which lasted seven or eight seconds." An agent of the United States, Mr. Ellicott, at that time at sea between Cape Florida and the West India Islands, was another spectator, and thus describes the scene:-"I was called up about three o'clock in the morning, to see the shooting stars, as they are called. The phenomenon was grand and awful. The whole heavens appeared as if illuminated with sky-rockets, which disappeared only by the light of the sun after daybreak. The meteors, which at any one instant of time appeared as numerous as the stars, flew in all possible directions, except from the earth, towards which they all inclined more or less; and some of them descended perpendicularly over the vessel we were in, so that I was in constant expectation of their falling on us." The same individual states that his thermometer, which had been at 80° Fahr. for four days preceding, fell to 56°, and, at the same time, the wind changed from the south to the north-west, from whence it blew with great violence for three days without intermission. The Capuchin missionary at San Fernando, a

successive years, and on the same day of the month as the two preceding, seemed to invest the meteoric showers with a periodical character; and hence originated the title of the November meteors. The chief scene of the exhibition was included within the limits of the longitude of 61° in the Atlantic Ocean, and that of 100° in Central Mexico, and from the North American lakes to the West Indies. Over this wide area, an appearance presented itself, far surpassing in grandeur the most imposing artificial fire-works. An incessant play of dazzlingly brilliant luminosities was kept up in the heavens for several hours. Some of these were of considerable magnitude and peculiar form. One of large size remained for some time almost stationary in the zenith, over the Falls of Niagara, emitting streams of light. The wild dash of the waters, as contrasted with the fiery uproar above them, formed a scene of unequalled sublimity. In many districts, the mass of the population were terror-struck, and the more enlightened were awed at contemplating so vivid a picture of the Apocalyptic image that of the stars of heaven falling to the earth, even as a figtree casting her untimely figs, when she is shaken of a mighty wind. A planter of South Carolina thus describes the effect of the scene upon the ignorant blacks :-"I was suddenly awakened by the most distressing cries that ever fell on my ears. Shrieks of horror and cries for mercy I could hear from most of the negroes of three plantations, amounting in all to about six or eight hundred. While earnestly listening for the cause, I heard a faint voice 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 me 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. Upwards of one hundred lay prostrate on the ground some speechless, and some with the bitterest cries, but with their hands raised, imploring God to save the world and them. The scene was truly awful; for never did rain fall much thicker than the meteors fell towards the earth; east, west, north and south, it was the same."

This extraordinary spectacle commenced a little before midnight, and reached its height

between four and six o'clock in the morning. The night was remarkably fine. Not a cloud obscured the firmament. Upon attentive observation, the materials of the shower were found to exhibit three distinct varieties:-1. Phosphoric lines formed one class apparently described by a point. These were the most abundant. They passed along the sky with immense velocity, as numerous as the flakes of a sharp snow-storm. 2. Large fire-balls formed another constituency of the scene. These darted forth at intervals along the arch of the sky, describing an arc of 30° or 40° in a few seconds. Luminous trains marked their path, which remained in view for a number of minutes, and in some cases for half an hour or more. The trains were commonly white, but the various prismatic colours occasionally appeared, vividly and beautifully displayed. Some of these fire-balls, or shooting stars, were of enormous size. Dr. Smith of North Carolina observed one which appeared larger than the full moon at the horizon. "I was startled," he remarks, "by the splendid light in which the surrounding scene was exhibited, rendering even small objects quite visible." The same, or a similar luminous body, seen at Newhaven, passed off in a north-west direction, and exploded near the star Capella. 3. Another class consisted of luminosities of irregular form, which remained nearly stationary for a considerable time, like the one that gleamed aloft over the Niagara Falls. The remarkable circumstance is testified by every witness, that all the luminous bodies, without a single exception, moved in lines, which converged in one and the same point of the heavens, a little to the southeast of the zenith. They none of them started from this point, but their direction, to whatever part of the horizon it might be, when traced backwards, led to a common focus. Conceive the centre of the diagram to be nearly overhead, and a proximate idea may be

formed of the character of the scene, and the uniform radiation of the meteors from the same source. The position of this radiant point among the stars was near y Leonis. It remained stationary with respect to the stars during the whole of the exhibition. Instead of accompanying the earth in its diurnal motion eastward, it attended the stars in their apparent movement westward. The source of the meteoric shower was thus independent of the earth's rotation, and this shows its position to have been in the regions of space exterior to our

atmosphere. According to the American Professor, Dr. Olmstead, it could not have been less than 2238 miles above the earth's surface.

The attention of astronomers in Europe, and all over the world, was, as may be imagined, strongly roused by intelligence of this celestial display on the western continent: and as the occurrence of a meteoric shower had now been observed for three years successively, at a coincident era, it was inferred that a return of this fiery hail-storm might be expected in succeeding Novembers. Arrangements were therefore made to watch the heavens on the nights of the 12th and 13th in the following years at the principal observatories; and though no such imposing spectacle as that of 1833 has been witnessed, yet extraordinary flights of shooting stars have been observed in various places at the periodic time, tending also from a fixed point in the constellation Leo. They were seen in Europe and America on November 13th, 1834. The following results of simultaneous observation were obtained by Arago from different parts of France on the nights of November 12th and 13th, 1836: