This term is derived from the Greek πτερόν, a meteor, and ἀστος, a stone, and denotes a stony substance, exhibiting peculiar characters, and the descent of which to the earth is usually accompanied by the appearance and explosion of a fire-ball.
Luminous meteors have in all ages been observed in the atmosphere. It is also well known that their disappearance has frequently been attended with a loud noise; but that they should moreover terminate in the fall of one or more solid bodies to the earth's surface, is a position so repugnant to our ordinary conceptions of the tenor of physical events, that we cannot admit it as a fact upon slight or scanty evidence.
One passage may be cited from the books of the Old Testament in corroboration of the descent of stones from the atmosphere. In the 11th verse of the 10th chapter of Joshua we find—"And it came to pass, as they fled from before Israel, and were in the going down to Beth-horon, that the Lord cast down great stones from heaven upon them unto Azekah, and they died."
If from sacred we turn to the early period of profane history, we shall find the annals of public events very copiously interspersed with notices of such strange appearances. Through the midst of fable which envelopes the history of the beatai we discern some characters which correspond with those of meteorolites. Thus in the Aethusa, a poem falsely ascribed to Orpheus, the crōngaros is said to be "rough, heavy, and black." Damascus, in an extract of his Life of Isidorus, preserved by Photius, relates that the beatai fell on Mount Libanus, in a "glow of fire."
A fragment of Sanchoniathon, preserved by Eusebius in his Preparatio Evangelii (i. 10), moreover informs us, that these stones were fabricated by the god Uranus or Heaven, one of whose four sons was named Beatai. In the same chapter we are told that Astarte found a "star" which had "fallen from heaven," and honoured it with consecration in the city of Tyre. The stone denominated "the mother of the gods," if we can believe Appian, Herodian, and Marcellinus, "fell from heaven."
Aristodemus, cited by the Greek scholiast on Piniar, asserts that it fell encircled by fire, upon a hill, at the feet of the Theban bard. It is said to have been of a black colour, and of an irregular shape. Herodian expressly declares, that the Phoenicians had no statue of the sun polished by the hand, but only a certain stone, circular below, and terminated acutely above, in the form of a cone, of a black colour, and that, according to report, it "fell from heaven," and was regarded by the people as the image of the sun.
Amongst various instances which might be selected from Livy is that of a shower of stones on the Alban Mount, in the reign of Tullus Hostilius, or about 652 B.C. The senate was assured that stones had really fallen, "hand alter quam quem grandinem venti glomeratam in terras agunt."
But one of the most remarkable cases which occurs in the records of antiquity is that which is mentioned in the 58th chapter of the second book of Pliny's Natural History, of a large stone which fell near Egospotamos in Thrace, in the second year of the 78th Olympiad, or, according to our chronology, about 467 years before the Christian era. Pliny assures us that this extraordinary mass was still shown in his day, and that it was as large as a cart, and of a burned colour. According to Plutarch, in the Life of Ly-sander, the inhabitants of the Chersonesus held the Thracian stone in great veneration, and exhibited it as a public show. This event is also recorded in that curious document, The Parian Chronicle, among the Arundelian marbles, in these terms—"From the time when the stone fell at Egospotamos, and the poet Simonides died at the age of ninety, during the archbishopship of Thengenesides at Athens, is 205 years." Pliny gives another instance of an aerolite which fell in Lucania about 56 B.C.; Meteoro-lite and Caesar records the descent of another at Accilla 46 B.C.
From this period till near the close of the fifteenth century, any historical notices which we have been enabled to collect are so vague and scanty, that in this abridged view of the subject we may pass them over in silence.
Professor Bantenschoven, of the central school of Colmar, first directed the attention of naturalists to some of the old chronicles, which commemorate, with much naïveté, and in the true spirit of the times, the fall of the celebrated stone of Ensisheim. The following account accompanied this very singular mass when it was suspended, in the church:—"In the year of the Lord 1492, on Wednesday, which was Martimas, eve, the 7th of November, there happened a singular miracle: for, between eleven o'clock and noon there was a loud peal of thunder, and a prolonged confused noise, which was heard to a great distance, and a stone fell from the air, in the jurisdiction of Ensisheim, which weighed 250 pounds, and the confused noise was, moreover, much louder than here. There a child saw it strike on a field situated in the upper jurisdiction, towards the Rhine and Inn, near to the district of Gisgard, which was sown with wheat; and did it no harm, except that it made a hole there; and then they conveyed it from that spot, and many pieces were broken from it, which the landvogt forbade. They therefore caused it to be placed in the church, with the intention of suspending it as a miracle, and many people came hither to see this stone."
Again, Trithemius, in his Hirsangiansian Annals, employs language to this effect:—"In the same year, on the 7th day of November, in the village of Santigaw, near the townlet of Ensisheim, not far from Basil, a city of Germany, a stone, called a thunder-stone, of a prodigious size, for we know from eye-witnesses that it weighed 255 pounds, fell from the heavens. Its fall was so violent that it broke into two pieces. The most considerable is still exhibited at the door of the church of Ensisheim, suspended by an iron chain, as a proof of the fact which we have mentioned, and to preserve it in the public recollection." We learn also from Paul Lang, "that there arose a furious storm on the 7th of November 1492, and that whilst the thunder roared, and the heavens appeared all on fire, a stone of enormous size fell near Ensisheim."
It is worthy of observation that these chroniclers lived at the period which they assign to the descent of the stone, and that although their names are hastening to oblivion, Trithemius yielded to few of his contemporaries in labour and learning; whilst Lang, a German Benedictine, had travelled in search of historical monuments, arraigned the license of the Catholic clergy, and applauded the independence of Luther and Melancthon.
In the Commentary of Surius, a Carthusian monk of Cologne, mention is made of a shower of large stones which fell in Lombardy in 1510. These stones were harder than flint, and smelled of sulphur. The heaviest weighed 120 pounds. The same event is more particularly related by Cardan, in his work entitled De Rerum Varietate (lib. xiv., c. 72). According to this author, near the River Adda, not far from Milan, and at five o'clock in the evening, about 1120 stones fell from the air, one of them weighing 120 pounds, and another 60 pounds. Many were presented to the French governor and his deputy. In the Memoirs of the Emperor Jehan-schah, written in Persian by himself, and translated by Colonel Kirkpatrick, is an account of the stone that fell in the province of Lahore in 1620; and Ferishta has recorded, in the true oriental style, the conversion of "this son of thunder," as he calls it, into two scimitars, a dagger, and a knife, by order of the emperor. The emperor says,—Here I had this substance weighed in my presence. Its weight was 160 tolas. I committed it to a skilful artizan, with orders to make of it a sabre, a knife, and a dagger. The workman reported that the substance was not malleable, but shivered into pieces under the hammer. Upon this I ordered it to be mixed with other iron. Conformably to my orders, three parts of the iron of lightning were mixed with one part of common iron, and from the mixture were made two sabres, one knife, and one dagger."
The celebrated Gassendi informs us, that on the 27th of November 1627, about ten o'clock in the morning, during a very clear sky, he saw a flaming stone, of the apparent diameter of 4 feet, fall on Mount Vaison, an eminence situated between the small towns of Perne and Guillaumes in Provence. This stone was surrounded by a luminous circle of different colours, nearly resembling the rainbow, and its fall was accompanied with a noise like the discharge of artillery. It weighed 59 pounds, and its specific gravity was to that of common marble as fourteen to eleven. It was of a dark metallic colour, and extremely hard. From a curious book printed at Paris in 1672, and now become very scarce, entitled "Conversations tirées de l'Académie de M. l'Abbé Bourdelot contenant diverses Recherches et Observations Physiques, par le Sieur Legallais," we make the ensuing extract:—“A member presents a fragment of two stones which fell near Verona, one of which weighed 300 and the other 200 pounds. These stones,” says he, “fell during the night, when the weather was perfectly mild and serene. They seemed to be all on fire, and came from above, but in a slanting direction, and with a tremendous noise. This prodigy terribly alarmed 300 or 400 eye-witnesses, who were at a loss what to think of it.”
No philosopher of the present day doubts the descent of stony bodies from the atmosphere; and the testimony of innumerable witnesses of their fall, with phenomena nearly similar, places meteorites among the established facts of natural science. If several of the early notices of them are obscure, we have, in the end of the last and in the present century, many descriptions of their appearance, on their descent, by intelligent witnesses; so that scepticism on this subject can be no longer entertained. It is also very remarkable, that wherever they have fallen, in Europe, in India, or America, their composition is nearly identically the same, and agrees in composition with no known mineral. This has been established by the careful experiments of the Hon. Mr Howard, of Vaquelin, Laugier, Klaproth, and Berzelius, as well as by the investigations of Bourron and many other mineralogists. Their general composition may be stated as follows:—Silica, 40 per cent.; malleable iron, 25; nickel, from 6 to 8; with a small quantity of iron pyrites, and variable proportions of alumina, lime, magnesia, manganese; with traces of chrome, cobalt, and sulphur. In the present century many have fallen in France, Germany, India, and America; and in our own islands one fell in Yorkshire in 1793, another in Gloucestershire in 1833, a third near Glasgow in 1804, and two in Ireland from 1810 to 1813. We shall now proceed to more detailed instances.
We have now to direct our attention to a report of M. de Lalande, inserted in the Historical Almanac of Bresse for 1756. In the month of September 1753, about one o'clock afternoon, when the weather was very hot and very serene, without the least appearance of clouds, a very loud noise, like the discharge of two or three cannons, was heard within the circumference of six leagues, but was of very short duration. This noise was loudest in the neighbourhood of Pont-de-Vesle; and at Liponnes, a village three leagues from the last-mentioned place, it was even accompanied with a hissing like that of a cracker. On the same evening there were found at Liponnes and at Pin two blackish masses, of a form nearly circular, but very uneven, which had fallen on ploughed ground, and sunk by their own weight to the depth of half a foot below the surface. One of them weighed about twenty pounds; and a fragment of one of them, weighing eleven and a half pounds, was preserved in the cabinet of M. Varenne de Beest at Dijon. The basis of these masses resembled a greyish whinstone, and was very refractory; and some ferruginous particles were disseminated in grains, filaments, or minute masses, throughout the substance of the stone, especially in its fissures. On the 15th of September 1760, according to the Abbé Bachelay, about half-past four o'clock afternoon, there appeared near the Chateau de Chevabrie, in the neighbourhood of Luze, a small town of the province of Maine, a stormy cloud, from which proceeded a loud peal of thunder, like the discharge of cannon, and followed by a noise which was mistaken by several people for the lowing of oxen. This sound was heard over a space of about two leagues and a half, but unaccompanied by any perceptible flame. The reapers in the parish of Perigueux, about three leagues from Luze, on hearing the same noise, looked up, and saw an opaque body, which described a curve, and fell on soft turf upon the high road from Mons, near which they were at work. They all quickly ran up to it, and found a sort of stone, nearly half of which was buried in the earth, and the whole so hot that it could not be touched. At first they ran away in a panic; but upon returning to the spot some time afterwards, they found the stone precisely in the same situation, and sufficiently cooled to admit of being handled and narrowly examined. It weighed seven ounces and a half, and was of a triangular form.
On the 20th of November 1768 a stone fell at Mauerkirchen, near the River Inn in Bavaria, which weighed 38 pounds, and was of a triangular form, being about eight inches in thickness. Its fall was accompanied by a hissing noise. The next remarkable case that has been recorded occurred on the 20th of August 1789 at Barbotan, near Roquefort, in the Landes of Bordeaux. A much more remarkable phenomenon, however, of the same description occurred near Agen on the 24th of July 1790. An inhabitant of St Sevère communicated the following particulars to M. Darcey the chemist, who was then resident at Paris:—“Our town's-people were yesterday very much alarmed. About a quarter-past nine o'clock in the evening there suddenly appeared in the atmosphere a fire-ball, dragging a long train, which diffused a very vivid light over the horizon. This meteor soon disappeared, and seemed to fall at one hundred paces from us. It was quickly followed by an explosion louder than that of a cannon or of thunder. Everybody dreaded being buried under the ruins of his house, which seemed to give way from the concussion. The same phenomenon was seen, and the report heard, in the neighbouring towns, as Mont de Marsan, Tartas, and Dax. The weather in other respects was very calm, without a breath of wind or a cloud, and the moon shone in all her brightness.” Those which fell on the houses produced a noise, not like that of stones, but rather of a substance which had not yet acquired compactness.
M. Baudin mentions, that as M. Carris of Barbotan and he were walking in the court of the Castle of Morines, about half-past nine o'clock in the evening of the 24th of July 1790, when the air was perfectly calm and the sky cloudless, they found themselves suddenly surrounded by a pale clear light, which obscured that of the moon, although the latter was nearly full. On looking up they observed, almost in their zenith, a fire-ball of a larger apparent diameter than that of the moon, dragging a tail which seemed to be five or six times longer than the diameter of its body, and which gradually tapered to a point; the latter ap- approaching to blood-red, though the rest of the meteor was of a pale white. This luminous body proceeded with great velocity from south to north, and in two seconds split into portions of considerable size, like the fragments of a bursting bomb. These fragments became extinguished in the air, and some of them, as they fell, assumed that deep red colour which had been observed at the point of the tail. Two or three minutes afterwards M. Baudin and his friend heard a dreadful explosion, like the simultaneous firing of several pieces of ordnance; but they were not sensible of any tremulous motion under their feet, although the concussion of the atmosphere shook the windows in their frames, and threw down kitchen utensils from their shelves. When these gentlemen removed to the garden the noise still continued, and appeared to be directly over their heads. Some time after it had ceased, they heard a hollow sound rolling in echoes for about 50 miles along the chain of the Pyrenees, and at the end of about four minutes gradually dying away in distance. At the same time a strong sulphurous odour was diffused in the atmosphere. The interval which occurred between the disruption of the meteor and the loud report induced M. Baudin to conjecture that this fire-ball must have been at least 8 miles from the earth's surface, and that it fell about 4 miles from Mormes.
"The latter part of my conjecture," says he, "was soon confirmed by an account which we received of a great many stones having fallen from the atmosphere at Juillac and in the neighbourhood of Barbotan." It appears, indeed, from the concurring testimony of intelligent persons worthy of credit, that the meteor really exploded at a little distance from Juillac, and that its fragments were found lying in an almost circular space of nearly 2 miles in diameter. Some of them weighed 18 or 20, and a few, it is alleged, even 50 pounds. M. de Carris procured one of 18 pounds, which he transmitted to the Academy of Sciences at Paris. That examined by M. Baudin was small, but heavy in proportion to its size, black on the outside, greyish within, and interspersed with many minute, shining, metallic particles.
Our chronological series of cases has now brought us to the fall of several meteorites near Sieña, the particulars of which, as reported by the Earl of Bristol and Sir William Hamilton, are recorded in the first part of the Philosophical Transactions for the year 1795 (p. 163). The date of the Sieña meteor is the 16th of June 1794. On the 13th of December in the following year, about three o'clock in the afternoon, another of these singular stones, weighing about 56 pounds, fell near the country-house of Captain Topham in Yorkshire. The captain's report, which is inserted in the Gentleman's Magazine for 1796, is distinct and satisfactory; whilst the chemical examination of the mass, detailed in Mr Howard's paper in the Philosophical Transactions for 1802, affords a still more decisive proof of its atmospheric origin. M. de Drée also found it to correspond exactly in aspect and character with fragments of meteoric stones from Benares and Ville-Franche. The original mass is larger than a man's head. It weighed 56 pounds, and is now in the British Museum.
Mr Southey, in his letters from Spain and Portugal, transcribes the authenticated relation of another instance of the descent of a stone from the clouds on the 19th of February 1796. But we pass to some of the most important details relative to the stone which is affirmed to have fallen near Ville-Franche, in the department of the Rhone, on the 12th of March 1798. It was transmitted to Professor Sage, member of the National Institute. "It is of an ash-grey colour," says M. Sage, "granulated, and speckled with gray, shining, and pyritous metallic points. One of its surfaces is covered with a dingy black enamel about the third of a line in thickness. This stone acts very powerfully on the magnetic needle."
An account of the same meteor was published in the Journal de Physique by M. de Drée. From his minute and deliberate investigation, it appears that the fire-ball had scarcely fixed the attention of the inhabitants of Sales and the adjacent villages, when its rapid approach, accompanied by a terrible whizzing noise, like that of an irregular hollow body traversing the air with unusual velocity, inspired the whole commune with alarm, especially when they observed it passing over their heads at an inconsiderable elevation. It left behind a long train of light, and emitted, with an almost unceasing crackling, small vivid flames like little stars. Its fall was remarked at the distance of only fifty paces by three labourers. These three witnesses attest the astonishing rapidity of the meteor's motion and the hissing which proceeded from the spot where it fell.
On the 19th of December 1798, about eight o'clock in the evening, the inhabitants of Benares and its neighbourhood observed in the heavens a very luminous meteor, in the form of a large ball of fire, which exploded with a loud noise, and from which a number of stones were precipitated near Krakhot, a village about 14 miles from the city of Benares. Mr Davis, the judge and magistrate of the district, affirmed that in brilliancy it equalled the brightest moonlight. "Of these stones," says Mr Howard, "I have seen eight nearly perfect; externally they were covered with a hard black coat or incrustation, which in some parts had the appearance of varnish or bitumen; and on most of them were fractures, which, from their being covered with a matter similar to that of the coat, seemed to have been made in the fall by the stones striking against each other, and to have passed through some medium, probably an intense heat, previous to their reaching the earth. Internally they consisted of a number of small spherical bodies of a slate colour, imbedded in a whitish gritty substance, interspersed with bright shining spicular, of a metallic or pyritical nature. The spherical bodies were much harder than the rest of the stone; the white gritty part readily crumbled on being rubbed with a hard body; and on being broken a quantity attached itself to the magnet, but more particularly the outside coat or crust, which appeared almost wholly attractable by it."
An account of the extraordinary shower of stones which fell near L'Aigle in Normandy, on 26th April 1803, appeared in the following letter addressed by M. Marais, an inhabitant of the place, to his friend in Paris:—"An astonishing miracle has just occurred in our district. Here it is, without alteration, addition, or diminution. It is certain that it is the truth itself. On Friday (26th of April), between one and two o'clock in the afternoon, we were roused by a murmuring noise like thunder. On going out we were surprised to see the sky pretty clear, with the exception of some small clouds. We took it for the noise of a carriage or of fire in the neighbourhood. We were then in the meadow, to examine whence the noise proceeded, when we observed all the inhabitants of the Pont de Pierre at their windows and in gardens, inquiring concerning a cloud which passed in the direction of from S. to N., and from whence the noise issued, although that cloud presented nothing extraordinary in its appearance. But great was our astonishment when we learned that many and large stones had fallen from it, some of them weighing 10, 11, and even 17 pounds, in the space between the house of the Buat family (half a league to the N.N.E. of L'Aigle) and Glas, passing by St Nicolas, St Pierre, &c., which struck us at first as a failure, but which was afterwards found to be true. The following is the explanation given of this extraordinary event by all who witnessed it:—They heard a noise like that of a cannon, then a double report still louder than the preceding, followed by a rumbling noise, which lasted about ten minutes, the same which we also heard, accompanied with hissings, caused by these stones, which were counteracted in their fall by the different currents of air, which is very natural in the case of such a sudden expansion. Nothing more was heard; but it is remarkable that, previously to the explosion, the domestic fowls were alarmed, and the cows bellowed in an unusual manner. All the country people were much dismayed, especially the women, who believed that the end of the world was at hand. A labourer at La Sapée fell prostrate on the ground, exclaiming, 'Good God, is it possible that thou canst make me perish thus? Pardon, I beseech thee, all the faults I have committed.' The most trifling objects, in fact, might create alarm; for it is not improbable that history offers no example of such a shower of stones as this. The piece which I send was detached from a large one weighing about 11 pounds, which was found between the house of the Buats and Le Fertey. It is said that a collector of curiosities purchased one of 17 pounds weight that he might send it to Paris. Everybody in this part of the country is desirous of possessing a whole stone, or a fragment of one, as an object of curiosity."
At the sitting of the Institute on the 9th of May, Fourcroy read a letter from L'Aigle addressed to M. Vaquelin, and which sufficiently corroborates the preceding statements. But we pass to the substance of M. Biot's letter addressed to the minister of the interior, and published in the Journal des Debats. This very eminent philosopher was deputed by government to repair to the spot, and collect all the authentic facts. He left Paris on the 5th of June, and instead of proceeding directly to L'Aigle, went first to Alençon, which lies 15 leagues to the W.S.W. of that place. He was informed on his way that a globe of fire had been observed moving towards the north, and that its appearance was followed by a violent explosion. From Alençon he journeyed through various villages to L'Aigle, being directed in his progress by the accounts of the inhabitants, who had all heard the explosion on the day and at the hour specified. Almost all the inhabitants of twenty hamlets, scattered over an extent of upwards of 2 square leagues, affirmed that they were eye-witnesses of a dreadful shower of stones which were darted from the meteor. The following is his summary of the whole evidence:—"On Tuesday, 6th Floreal, year 11, about one o'clock p.m., the weather being serene, there was observed from Caen, Pont d'Audemer, and the environs of Alençon, Falaise, and Verneuil, a fiery globe of a very brilliant splendour, and which moved in the atmosphere with great rapidity. Some moments after there was heard at L'Aigle, and in the environs of that town, in the extent of more than 30 leagues in every direction, a violent explosion which lasted five or six minutes. At first there were three or four reports like those of cannon, followed by a kind of discharge which resembled the firing of musketry; after which there was heard a dreadful rumbling like the beating of a drum. The air was calm and the sky serene, except a few clouds, such as are frequently observed. This noise proceeded from a small cloud which had a rectangular form, the largest side being in a direction from E. to W. It appeared motionless all the time that the phenomenon lasted; but the vapours of which it was composed were projected momentarily from different sides by the effect of the successive explosions. This cloud was about half a league to the N.N.W. of the town of L'Aigle. It was at a considerable elevation in the atmosphere, for the inhabitants of two hamlets, a league distant from each other, saw it at the same time above their heads. In the whole canton over which this cloud was suspended, there was heard a hissing noise like that of a stone discharged from a sling, and a great many mineral masses, exactly similar to those distinguished by the name of meteoric stones, were seen to fall. The district in which these masses were projected forms an elliptical extent of about 24 leagues in length, and nearly 1 in breadth, the greatest dimension being in a direction from S.E. to N.W., forming a declination of about 22 degrees. This direction, which the meteor must have followed, is exactly that of the magnetic meridian, which is a remarkable result. The greatest of these stones fell at the south-eastern extremity of the large axis of the ellipse, the middle-sized in the centre, and the smaller at the other extremity. Hence it appears that the largest fell first, as might naturally be supposed. The largest of all those that fell weighs 17½ pounds. The smallest which I have seen weighs about 2 gros (a thousandth part of the last). The number of all those which fell is certainly above two or three thousand."
It deserves to be remarked, that the L'Aigle stones were very friable for some days after their descent, that they gradually acquired hardness, and that after they had lost the sulphurous odour on their surface, they still retained it in their substances, as was found by breaking them. That some of the relations to which we have referred are vague and unsatisfactory cannot be denied, but the circumstantial testimony conveyed by others is pointed and positive; and the whole mass of historical proof, especially when combined with the argument deduced from the identity of the physical and chemical constitution of the stones, appears to us to be altogether irresistible.
In the course of our inquiry into this novel and interesting subject we have ascertained a variety of circumstances which render it highly probable, if not indubitable, that those detached masses of native iron, the history of which has so often staggered and perplexed the geologist, are only modifications of meteoric depositions. The Tartars, for example, ascribe the descent of the Siberian mass described by Pallas, Chladni, and others, to a period that is lost in the remoteness of antiquity; and whilst tradition thus favours our hypothesis, the analogy which is obviously observable, in point of texture and chemical characters, with those of other solid bodies the fall of which is no longer questioned, strengthens tradition. According to the discoveries of Proust and Klaproth, native iron, reputed meteoric, differs from that which occurs in a fossil state by the presence of nickel. The former of these celebrated analysts obtained 50 grains of sulphate of nickel from 100 of the South American mass, and his results are corroborated by Mr Howard and the Count de Bourbon.
Of the two pieces of Siberian iron now in the British Museum, one of which was transmitted by Dr Pallas, weighs several pounds; and another presents a cellular and ramified texture analogous to that of some very light and porous volcanic scoriae. When attentively examined, there may be perceived in it not only empty cells, but also impressions or cavities of greater or less depth, and in some of which there remain specks of olivine. The iron itself is very malleable, and may be easily cut with a knife or flattened under the hammer. The specific gravity is 6487, which is obviously inferior to that of unforged iron that has undergone fusion, and may be partly owing to the oxidization of the surface of the iron, and partly to the many minute cavities in its substance, which are often rendered visible by fracture, and which have their surface also oxidized. The fracture is shining and silvery, like that of white cast-iron; but its grain is much smoother and finer, and it is much more malleable when cold. The heavier specimen is more solid and compact, exhibiting no cavities or pores, though its surface is ramified and cellular. So blended and incorporated is its compact part with the olivine mentioned above, that if the whole of the latter could be subtracted, the remainder would consist of iron in the metallic state, and would display the same cellular appearance as the preceding specimen, or as the superficial por- Meteoricite.
"I cannot help observing," says the Count de Bourbon, "that there appears to exist a very interesting analogy between these transparent nodules and the globules I described as making part of the stones said to have fallen on the earth. This analogy, though not a very strong one, may lead us to suppose that the two substances are similar in their nature, but that the globules are less pure, and contain a greater quantity of iron."
Having now, as we apprehend, sufficiently established the existence and nature of meteorites, we hope that our readers will excuse us from enlarging on the various causes which have been assigned for their origin, as these seem to lie beyond the reach of our present state of knowledge. After a candid and patient review of the principal theories, we conceive that most of them are open to many and formidable objections.
The terrestrial hypotheses, we believe, begin already to be generally abandoned as untenable. Until the phenomenon of exploding meteors had been distinctly observed and recorded, Lemery and others could maintain, with some degree of plausibility, that lightning might tear up the ground, and convert soil into a compact mass. But the appearances of a thunder-storm and of a fire-ball are now ascertained to differ in various important particulars. Spectators worthy of credit have seen the latter terminate in the fall of solid bodies, and the composition of these solid bodies has been found to differ from that of all the known fossil substances on the surface of the globe. It is in vain, then, to allege that they are formed on the ground by common lightning, which has often produced very extraordinary effects, but which never generated thousands of stones in fine calm weather. The supposition that such stones have been projected from some of our volcanoes is hardly less conceivable. The ashes which accompany a violent eruption of Etna or Vesuvius have, from their levity, been carried to a very considerable distance; but we are totally unacquainted with any projectile force which could dart solid masses many hundreds miles through such a dense medium as the atmosphere. The compact lavas of burning mountains are never found remote from the scene of their formation, and none of them present the characters and aspect of the stones which we have described. Of those who contend for the atmospherical formation of meteorites, scarcely any two agree in regard to the manner in which such formation is effected. The celebrated Munchenbrock in one of his writings ascribes the descent of stones from the air to earthquakes and volcanic eruptions; an opinion which later observations have disproved. In other passages, however, he seems to incline to a modification of the atmospherical hypothesis, and endeavours to trace the origin of shooting stars to an accumulation of the volatile matters which are suspended in the air. M. Salverte has given extension to the theory of formation from vapours by having recourse to the agency of hydrogen gas. According to him, in consequence of the decomposition of water, which is constantly going on at the surface of the earth, immense quantities of hydrogen gas are continually rising into the atmosphere, and ascending to its higher regions. As this gas is capable of dissolving metals, it carries along with it a portion of iron and nickel. During thunderstorms this gas is kindled by electricity; the metals are deposited, reduced, melted, and vitrified; in other words, meteorites are produced and stones formed. But this hypothesis is scarcely more satisfactory than the others. It does not account for the presence of magnesia and silica, nor does it explain why the stones are always composed of the same materials. In general we may observe, that if the origin of meteorites be really atmospherical, the matters of which they are composed must have existed in one of two states, namely, in very attenuated particles or concretions of the matters themselves volatilized and held in solution in the air, or only in the elements of these matters. In the first case, when abandoned by their menstruum to their reciprocal tendencies, they would unite by aggregation only; in the second, by chemical combination. M. Izarn, who has published a treatise on Atmospheric Lithology, has entered into a somewhat obscure exposition of his own theory, founded on this principle. We shall give the summary, as nearly as we can, in his own words:
"Gaseous substances, arranged in spherical masses in the upper regions of the air, being admitted, the various agitations of the atmosphere should naturally waft some of these masses from their insulating medium into one capable of combining with them. If the combination begins, the disengagement of light is explained. In proportion as the combination advances the specific gravities are changed, and consequently a change of place will commence. Motion being once impressed, the mass traverses other media, capable of supplying new principles, which, still increasing the weight, determine the curve; and when at length the principles which are at work have attained the requisite proportion for extinguishing the elements in the birth of the compound, the grand operation is announced by the explosion, and the product takes its place among the solids." That the stones in question are produced by chemical combination in the higher regions of the atmosphere, and that they are thus formed from their own elements, are suppositions fully as probable as any that have been advanced on the subject; but whether the union of their parts be effected in the manner detailed by M. Izarn we are unable to determine, because our range of data is as yet too circumscribed to warrant any specific or decisive conclusions.
A much bolder theory has been suggested, and its possibility demonstrated, by Laplace, who shows that meteorites may be the products of lunar volcanoes. We shall present the reasoning upon which this extraordinary hypothesis is founded, in the popular and perspicuous language of Dr Hutton of Woolwich. The respect due to the name of Laplace will justify the length of the extract. "As the attraction of gravitation extends through the whole planetary system, a body placed at the surface of the moon is affected chiefly by two forces, one drawing it toward the centre of the earth, and another drawing it toward that of the moon. The latter of these forces, however, near the moon's surface, is incomparably the greater. But as we recede from the moon, and approach toward the earth, this force decreases, whilst the other augment; till at last a point of station is found between the two planets, where these forces are exactly equal, so that a body placed there must remain at rest; but if it be removed still nearer to the earth, then this planet would have the superior attraction, and the body must fall towards it. If a body, then, be projected from the moon towards the earth, with a force sufficient to carry it beyond the point of equal attraction, it must necessarily fall on the earth. Such, then, is the idea of the manner in which the bodies must be made to pass from the moon to the earth, if that can be done, the possibility of which is now necessary to be considered. Now, supposing a mass to be projected from the moon, in a direct line towards the earth, by a volcano or by the production of steam by subterranean heat; and supposing, for the present, these two planets to remain at rest; then it has been demonstrated, on the Newtonian estimation of the moon's mass, that a force projecting the body with a velocity of 12,000 feet in a second would be sufficient to carry it beyond the point of equal attraction. But this estimate of the moon's mass is now allowed to be much above the truth; and, on M. Laplace's calculation, it appears that a force of little more than half the above power would be sufficient to produce the effect; that is, a force capable of projecting a body with a velocity of less than a mile and a half per second. But we have known cannon-balls pro- jected by the force of gunpowder with a velocity of 2500 feet per second or upwards; that is, about half a mile. It follows, therefore, that a projectile force, communicating a velocity about three times that of a cannon-ball, would be sufficient to throw the body from the moon beyond the point of equal attraction, and cause it to reach the earth.
Now there can be little doubt that a force equal to that is exerted by volcanoes on the earth, as well as by the production of steam by subterranean heat, when we consider the huge masses of rock, so many times larger than cannon-balls, thrown on such occasions to heights also so much greater. We may easily imagine, too, such cause of motion to exist in the moon as well as in the earth, and that in a superior degree, if we may judge from the supposed symptoms of volcanoes recently observed in the moon by the powerful tubes of Dr Herschel; and still more, if we consider that all projections from the earth suffer an enormous resistance and diminution by the dense atmosphere of this planet, whilst it has been rendered probable, from optical considerations, that the moon has little or no atmosphere at all to give any such resistance to projectiles.
Thus, then, we are fully authorized in concluding that the case of possibility is completely made out; that a known power exists in nature capable of producing the foregoing effect, of detaching a mass of matter from the moon, and transferring it to the earth in the form of a flaming meteor or burning stone; at the same time we are utterly ignorant of any other process in nature by which the same phenomenon can be produced. Having thus discovered a way in which it is possible to produce those appearances, we shall now endeavour to show, from all the concomitant circumstances, that these accord exceedingly well with the natural effects of the supposed cause, and thence give it a very high degree of probability.
This important desideratum will perhaps be best attained by examining the consequences of a substance supposed to be projected by a volcano from the moon into the sphere of the earth's superior attraction, and then comparing those with the known and visible phenomena of the blazing meteors or burning stones that fall through the air on the earth. And if in this comparison a striking coincidence or resemblance shall always or mostly be found, it will be difficult for the human mind to resist the persuasion that the assumed cause involves a degree of probability but little short of certainty itself. Now the chief phenomena attending these blazing meteors or burning stones are these:
1. That they appear to blaze out suddenly; 2. That they move with a surprisingly rapid motion, nearly horizontal, but a little inclined downwards; 3. That they move in several different directions with respect to the points of the compass; 4. That in their flight they yield a loud whizzing sound; 5. That they commonly burst with a violent explosion and report; 6. That they fall on the earth, with great force, in a sloping direction; 7. That they are very hot at first, remain hot a considerable time, and exhibit visible tokens of fusion on their surface; 8. That the fallen story masses have all the same external appearance and texture, as well as internally the same nature and composition; 9. That they are totally different from all our terrestrial bodies, both natural and artificial.
Now these phenomena we shall proceed to compare with the circumstances of a substance projected by a lunar volcano, and in the order in which they are here enumerated. And, first, with respect to the leading circumstance, that of a sudden blazing meteoric appearance, which is not that of a small bright spark, first seen at an immense distance, and then gradually increasing with the diminution of its distance. And this circumstance appears very naturally to result from the assumed cause. For, the body being projected from a lunar volcano, may well be supposed in an ignited state, like inflamed matter thrown up by our terrestrial volcanoes, which, passing through the comparatively rarefied vacuum in the space between the moon and the earth's sensible atmosphere, it will probably enter the superior parts of this atmosphere with but little diminution of its original heat; from which circumstance, united with that of its violent motion, this being ten or twelve times that of a cannon-ball, and through a part of the atmosphere probably consisting chiefly of the inflammable gas rising from the earth to the top of the atmosphere, the body may well be supposed to be suddenly inflamed, as the natural effect of these circumstances; indeed it would be surprising if it did not. From whence it appears, that the sudden inflammation of the body on entering the earth's atmosphere is exactly what might be expected to happen.
To trace the body through the earth's atmosphere, we are to observe that it enters the top of it with the great velocity acquired by descending from the point of equal attraction, which is such as would carry the body to the earth's surface in a very few additional seconds of time if it met with no obstruction. But as it enters deeper in the atmosphere, it meets with still more and more resistance from the increasing density of the air, by which the great velocity of 6 miles per second must soon be greatly reduced to one that will be uniform, and only a small part of its former great velocity. This remaining part of its motion will be various in different bodies, being more or less as the body is larger or smaller, and as it is more or less specifically heavy; but for a particular instance, if the body were a globe of 12 inches diameter, and of the same gravity as the atmospheric stones, the motion would decrease so as to be little more than a quarter of a mile per second of perpendicular descent. Now, whilst the body is thus descending, the earth itself is affected by a twofold motion, both the diurnal and the annual one, with both of which the descent of the body is to be compounded. The earth's motion of rotation at the equator is about 17 miles in a minute, or two-sevenths of a mile in a second; but in the middle latitudes of Europe little more than the half of that, or little above half a quarter of a mile, in a second; and if we compound this motion with that of the descending body, as in mechanics, this may cause the body to appear to descend obliquely, though but a little, the motion being nearer the perpendicular than the horizontal direction. But the other motion of the earth, or that in its annual course, is about 20 miles in a second, which is eighty times greater than the perpendicular descent in the instance above mentioned; so that, if this motion be compounded with the descending one of the body, it must necessarily give it the appearance of a very rapid motion in a direction nearly parallel to the horizon, but a little declining downwards; a circumstance which exactly agrees with the appearances of these meteoric bodies, as stated in the second article of the enumerated phenomena.
Again, with regard to the apparent direction of the body; this will evidently be various, being that compounded of the body's descent and the direction of the earth's annual motion at the time of the fall, which is itself various in the different seasons of the year, according to the direction of the several points of the ecliptic to the earth's meridian or axis. Usually, however, from the great excess of the earth's motion above that of the falling body, the direction of this must appear to be nearly opposite to that of the former. And, in fact, this exactly agrees with a remark made by Dr Halley, in his account of the meteors in his paper above given, where he says that the direction of the meteor's motion was exactly opposite to that of the earth in her orbit. And if this shall generally be found to be the case, it will prove a powerful confirmation of this theory of the lunar substances. Unfortunately, however, the observations on this point are very few, and mostly inaccurate; the angle or direction of the fallen stones has not been recorded, and that of the flying meteor commonly mistaken; all the various observers giving it a different course, some even directly the reverse of others. In future it will be very advisable that the observers of fallen stones observe and record the direction or bearing of the perforation made by the body in the earth, which will give us perhaps the course of the path nearer than any other observation.
4. In the flight of these meteoric stones it is commonly observed that they yield a loud whizzing sound. Indeed, it would be surprising if they did not. For if the like sound be given by the smooth and regularly-formed cannon-ball, and heard at a considerable distance, how exceedingly great must be that of a body so much larger, which is of an irregular form and surface, too, and striking the air with fifty or a hundred times the velocity.
5. That they commonly burst and fly in pieces in their rapid flight is a circumstance exceedingly likely to happen, both from the violent state of fusion on their surface, and from the extreme rapidity of their motion through the air. If a grinding-stone, from its quick rotation, be sometimes burst, and fly in pieces, and if the same thing happen to cannon-balls when made of stone and discharged with considerable velocity, merely by the friction and resistance of the air, how much more is the same to be expected to happen to the atmospheric stones, moving with more than fifty times the velocity; and when their surface may well be supposed to be partly loosened or dissolved by the extremity of the heat there.
6. That the stones strike the ground with a great force, and penetrate to a considerable depth, as is usually observed, is a circumstance only to be expected from the extreme rapidity of their motion and their great weight, when we consider that a cannon-ball or a mortar-shell will often bury itself many inches, or even some feet, in the earth.
7. That these stones, when soon sought after and found, are hot, and exhibit the marks of recent fusion, are also the natural consequences of the extreme degree of inflammation in which their surface had been put during their flight through the air.
8. That these stony masses have all the same external appearance and contexture, as well as internally the same nature and composition, are circumstances that strongly point out an identity of origin, whatever may be the cause to which they owe so generally uniform a conformation. And when it is considered,
9. That in those respects they differ totally from all terrestrial compositions hitherto known or discovered, they lead the mind strongly to ascribe them to some other origin than the earth we inhabit; and none so likely as coming from our neighbouring planet.
Upon the whole, then," continues Dr Hutton, "it appears highly probable that the flaming meteors and the burning stones that fall on the earth are one and the same thing. It also appears impossible, or in the extreme degree improbable, to ascribe these either to a formation in the superior parts of the atmosphere, or to the eruptions of terrestrial volcanoes, or to the generation by lightning striking the earth. But, on the other hand, that it is possible for such masses to be projected from the moon so as to reach the earth, and that all the phenomena of these meteors or falling stones, having a surprising conformity with the circumstances of masses that may be expelled from the moon by natural causes, unite in forming a body of strong evidence that this is in all probability actually the case."
M. Poisson, a very ingenious French mathematician, has shown, by an algebraical calculation, the possibility of a projectile reaching our planet from the moon. His calculation, however, which may be found in the work of Izarn quoted above, proceeds on the supposition that our satellite has no atmosphere, or next to none. There are, no doubt, appearances which seem to favour this supposition, but they do not amount to positive proof of the fact.
The hypothesis of Dr Chladni, which likewise boasts of its advocates, deserves to be stated. As earthly, metallic, and other particles form the principal component parts of our planet, amongst which iron is the prevailing part, other planetary bodies, he affirms, may consist of similar, or perhaps the same, component parts, though combined and modified in a very different manner. There may also be dense matters accumulated in smaller masses, without being in immediate connection with the larger planetary bodies, dispersed throughout infinite space, and which being impelled either by some projecting power or attraction, continue to move until they approach the earth or some other body, when, being overcome by attractive force, they immediately fall down. By their exceeding great velocity, which is increased by the attraction of the earth and the violent friction in the atmosphere, a strong electricity and heat must necessarily be excited, by which means they are reduced to a flaming and melted condition, and great quantities of vapour and different kinds of gases are thus disengaged, which distend the liquid mass to a monstrous size, until, by still further expansion of these elastic fluids, they must at length disintegrate.
Such are the principal hypotheses which have been advanced on the origin of meteorites. We shall conclude this article by a list of these bodies contained in the British Museum.
Aerolites in the British Museum, with Time and Place of their descent, when known.
Ensisheim, 1402; Reichstadt, Bohemia, 1723; Bechin, Bohemia, 1753; Agram, Croatia, 1754; Saharampore, Delhi, 1758; Maurkirchen, Austria, 1768; Bobric, Charkow, 1787; Siena, Italy, 1794; Thwing, Yorkshire, 1795; Sales, France, 1798; Benares, India, 1798; L'Aigle, France, 1803; Borgo, Parma, 1804; Possil, near Glasgow, 1804; Timochin, Russia, 1807; Weston, Connecticut, 1807; Casignano, Parma, 1808; Stammer, Moravia, 1808; Tipperary, Ireland, 1810; Berlanguilles, Spain, 1811; La Vendée, France, 1812; Adare, Limerick, 1813; Wilberg, Finland, 1814; Agen, France, 1814; Chassigny, France, 1815; North Carolina, America, 1816; Joossan, France, 1819; Javaria, France, 1821; Nanjemoy, Maryland, 1822; Sandwich Islands, 1825; Nashville, Tennessee, 1826; Virginia, 1828; Borer, India, 1829; Chavallat, India, 1831; Tennessee, 1833; Aldworth, Gloucestershire, 1832; Bekkerveld, Cape of Good Hope, 1838; Little Piney, Missouri, 1839; Triguierre, France, 1841; Carthage, Tennessee, 1847; Bishopville, South Carolina, 1847; Cabarras, North Carolina, 1849.
Fragments of Meteoric Iron, date of fall unknown.
1. Part of the Otumpa mass sent from South America by Sir Woodbine Parish.—It weighs 1400 lb.; 2. Part of the Siberian mass of Pallas; 3. Aix-la-Chapelle; 4. Tennessee; 5. Alabama; 6. Kamischdorf, Saxony; 7. Lockport, New York; 8. Red River, Texas; 9. Arva, Hungary; 10. Elbegen, Bohemia; 11. Cape of Good Hope; 12. Heidelberg; 13. Durango, Mexico; 14. Zacatecas, do.; 15. Xiquipilco, do.; 16. Atacama, Bolivia; 17. Gran-Chaco, Peru; 18. Lenarto, Hungary; 19. Green County, Tennessee; 20. Bendigo, Brazil; 21. Smith, do.; 22. Kentucky; 23. Cocke County, Tennessee; 24. Lake of Lakes, Brandenburg; 25. Colonna di Bracciano, Milan; 26. Equipped knives of meteoric iron, brought by Captain Ross from Lat. 76. 12. N., Long. 53. W.
For further information on the subject of this article, see Izarn's Lithologie Atmosphérique; Biot's Relation d'un Voyage fait dans le Departement de l'Orne, pour constater la realite d'un Meteor observé à L'Aigle; Böttiger's Observations on the Accounts given by Ancient Authors of Stones said to have fallen from the Clouds; Fulda's Memoir on Fire-Balls; Cavallo's Elements of Natural Philosophy; Klaproth on Meteoric Stones; Soldani's Account of the Tuscan Meteor; Chladni's Treatise on the Siberian Mass of Iron; Mr Edward King's Remarks concerning Stones said to have fallen from the Clouds; and the Transactions of several learned societies.