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rences, as might be supposed, have in all former times, and by every people, been similarly made the subject of superstitious belief. The Ancyle or sacred shield of Numa, the holy Kaaba of Mecca, the sword of the Mongolian Emperor, and the great stone of the pyramid at Cholula in Mexico, have all the same history annexed to them. They fell from heaven, and were venerated in their presumed divine origin. These falling stones, however, though more wonderful in many respects, were much less frequent than the meteoric lights which blazed before the eyes of nations ; and they were for the most part very vaguely recorded. As we shall see afterwards, it is only within the last half-century that science has fully admitted them within her pale-reluctantly, it

may almost be said, as well as tardily; and resting even more on proofs furnished by the physical characters of the falling bodies, than on the historical evidence of their descent.

Nevertheless, it is chiefly to the recognition of these Aerolites, or falling stones, that we owe the zealous scientific research which has since been given to the subject of meteors. However wonderful these phenomena might be in themselves, their aspects and periods were seemingly so irregular as to render them insusceptible of that classification of facts which is the basis of all true science. The untutored gaze of the multitude was for ages as productive of results as the observation of the naturalist; and until very recently the theories of the latter scarcely went beyond certain vague notions of inflammable gases or electrical actions in the atmosphere. The bog-vapour kindled above the earth, instead of on its surface--and, yet more, the phenomenon of lightning in its various forms--offered explanations just plausible enough to check further investigation; and when Franklin (now exactly one hundred years ago) first drew electrical sparks from a thundercloud, it seemed as if a sufficient cause for meteoric appearances had been fully obtained. Yet, though the dominion of this great element of Electricity has been extending itself to our knowledge ever since, we shall presently see that other causes are here concerned ; and that we must carry our speculations still higher, before we can compass all the facts which modern observation has placed before us.

It will be readily conceived how much the admission of the fact, that Meteors are sometimes accompanied by the precipitation of stones or earthy and metallic matters from the sky, affected every part of this inquiry. And when Chemistry intervened, disclosing the singular and very similar composition of the bodies thus strangely conveyed to us, it became obvious that new elements were concerned, of which science was required to take larger cognizance. About the same period, research was more

exactly

exactly applied to determine the height, velocity, and direction of meteors, and especially of falling stars, while luminous to the eye; the results of which inquiry, though embarrassed by various difficulties, tended yet further to remove their physical causes beyond the region of our globe, by showing their elevation above the atınosphere, their vast rapidity of passage through space, and lines of movement involving other forces than that of simple gravitation towards the earth. And when to such researches were added, more recently, certain remarkable facts as to the periodicity of falling stars, the inquiry assumed at once a cosmical character, associating itself with some of the movements and higher laws of the planetary system,

We have sketched this preliminary outline of the subject, from a feeling of the interest which ever attaches to the successive stages of a new science—those steps by which we ascend from the rude, doubtful, or superstitious record of isolated facts, to the absolute proof, the classification of phenomena, and the determination of the physical laws which govern them. Such notices are not more instructive as to the philosophy of the material world than in relation to the history of man himself, thus advancing in knowledge and power amidst the elements which surround him.*

Though the subject of Meteors was thus brought within the domain of science, the difficulty remained of giving any classification to the phenomena, on which to base inquiry into their causes and physical connexions. On what principle was it possible to arrange appearances so vague and various in time, place, magnitude, and brilliancy? The simplest division is the only one yet admissible; expressing little more than those external aspects to which we have already alluded, without reference to the physical causes which are doubtless concerned in their varieties. First in order we have the globes or balls of light (bolides), appearing suddenly, and having certain physical characters, to which we shall afterwards advert. Secondly, falling or shooting stars (étoiles filantes), seen at all times and in all countries, but more numerously at certain periods, and more frequently under the clear skies of tropical regions. Thirdly, Aerolites, or meteoric stones, differing greatly in size and form, but with various characters showing a common origin, and this wholly alien to the planet on which they fall.

The spirit of inquiry awakened on the subject of Meteors, and the objects thus far defined, it was natural to recur to history and

* It has been well said by Laplace, ‘La connaissance de la méthode qui a guidé l'homme de génie n'est pas moins utile au progrès de la science, et même à sa propre gloire, que ses découvertes.'

tradition

tradition for evidences of similar phenomena in prior ages. This research, as we have already intimated, was fertile of curious results-derived as well from the classical writers of Greece and Rome, as from the records of the dark ages and of every intervening century to our own time. The most remote regions, as well as periods, contributed to this testimony—the facts sometimes coloured by superstition, sometimes obscured by imperfect report ; but numerous and exact enough for comparison with our own observations, and giving full proof of the uniformity of the phenomena throughout. Poetry naturally busied itself with these vagrant lights of heaven, and we might cite various passages from the Greek and Latin poets, which, though in some part ambiguous from the association of lightning with meteoric appearances, yet manifestly include the latter in their appeal to the imagination.* The historians of antiquity denote them in more or less detail, and with various degrees of belief. The naturalists of Greece and Rome, from Aristotle down to Seneca and Pliny, have not only left descriptions copious enough to identify all the appearances with those of our own time, but have here and there offered suggestions as to natural causes which are fairly admissible among the hypotheses of more recent date.

But the highest interest in these records of past times attaches itself to the fall of Aerolites; and as we propose to take this class of meteors first into view, we may reasonably dwell for a moment upon their early history. The phrases of Lapidibus pluit, Crebri ceciderunt a cælo lapides, &c., are familiar to us from Livy, and may no longer be disregarded as the idle tales of a superstitious age. Æschylus, in the fragment we possess of his Prometheus Unbound, alludes to a shower of rounded stones sent down by Jupiter from a cloud. But the most remarkable and authentic record of antiquity is that of the massive stone which fell in the 78th Olympiad (about the time of the birth of Socrates), at Ægospotamos on the Hellespont—the place soon afterwards dignified, or defaced, as opinion may be, by that naval victory of Lysander which subjected Athens and Greece, for a time, to the Spartan power. The philosopher Anaxagoras was said to have predicted the fall of this stone from the Sun-a prediction, doubiless, like many others, following after the event. It is expressly mentioned by Aristotle; by the author of the Parian

* Virgil, in the more practical description of his Georgics, connects falling stars with the approach of wind

Sæpe etiam stellas, vento impendente, videbis

Præcipites cælo labi, &c. Both Theophrastus and Pliny admit the same idea. If this connexion were generally true, which we doubt, it probably depends merely on the rising wind dispelling vapours which before hid these meteors from sight,

Chronicle;

Chronicle; by Diogenes of Apollonia, who speaks of it as falling in flames; and most fully by Plutarch and Pliny, both of whom distinctly state it to be shown in their time that is, in the sixth century after its fall. Pliny's description is well marked — Qui lapis etiam nunc ostenditur, magnitudine vehis, colore adusto; and he adds the fact that a burning comet (meteor) accompanied its descent.*

We see no cause whatever to doubt the authenticity of this statement, of which the very phrase colore adusto is a striking verification. If the mass remained visible, and of such magnitude as described, down to Pliny's time, it is far from impossible that it may even now be re-discovered—with the aid, perchance, of some stray tradition attached to the place—surviving, as often happens, the lapse of ages, the changes of human dominion, and even the change of race itself on the spot.

on the spot. Only one slight effort, as far as we know, has been made for the recovery of this ancient aerolite. We marvel that some of our many Oriental travellers do not abstract a few days from the seraglios, mosques, and bazaars of Constantinople-(and, we fear, we must further add, from the lounging life of the Pera Hotel)—to engage deliberately in the attempt. Fame earned by discovery in travel is no longer so common a commodity that the chances of it should be disdained. In this case the research, if successful, would be of interest enough both for history and science to perpetuate a man's name.f

While

* Plutarch, who reasons with force and pertinency as to the origin of this stone (in Vitâ Lysandri), explicitly states that it was still held in much veneration by the inhabitants of the Chersonesus. He also speaks of its vast size, and of the traditiou of a fiery cloud or globe wbich preceded its fall. In his book De Placit. Philos. he alludes to it again, a8 πυροειδως κατενεχθεντα αστερα πετρινον. Pliny mentions a smaller meteoric stone, religiously preserved in the gymnasium at Abydos, also said to have been predicted by Anaxagoras. This coincidence of time and place might lead to the suspicion that both were derived from the same meteor. He further notices a stone of recent fall which he had himself seen at Vocontii in the province of Gallia Narbonensis—now Vaison in Provence.

+ Though the locality of this stone is not further indicated than by the statement of its fall at Ægospotamos, yet the invariable manner in which it is thus described defines tolerably well the district to be examined. We learn from the old geographers that there was a town called Ægospotami on the Thracian side the Hellespont, and we may infer a stream or streams, from which its name was derived. The description of the naval fight and the situatiou relatively to Lampsacus (the modern Lamsaki) further define the locality within certain limits. The traveller devoting himself to the research might make his head-quarters at various places near to the spot in question. He should render himself previously familiar with the aspect of meteoric stones, as now seen in the Museums and Mineralogical Cabinets throughout Europe. He must study the character of the rocks and fragmentary masses in the vicinity, so as more readily to appreciate the differences of aspect. He must expect the possibility of a small part only of the mass appearing above the surface; and his eye must be awake and active for any such partial appearances. If the stone sought for were wholly concealed by alluvial deposits, the research of course would be vain, unless happily aided by some VOL. XCII. NO. CLXXXIII.

G

local

While the antiquity of Greece and Rome, as well as the middle ages of Europe, furnish us only with scattered notices of these aerolites, it is far otherwise with the Chinese—that singular people, whose language, institutions, and methods of thought might almost suggest them as a race of men struck off from some other planet. There exist in China authentic catalogues of the remarkable meteors of all classes, aerolites included, which have appeared there during a period of 2400 years. To give an idea of the minuteness of these records the translation of which we owe to the lamented Ed. Biot-it is enough to mention that in the three centuries from A.D. 960 to 1270 not fewer than 1479 meteors are registered by the Chinese observers, who seem to have been officially employed for this purpose. It is only of late years that the science of Europe has placed itself in competition with these extraordinary documents. Though instances of falling stones were continually multiplying themselves in France, England, Germany, Italy, and elsewhere, the only memoirs we know on the subject, before the time of Chladni, are that of the Jesuit Domenico Troili, and another we shall afterwards notice. The work of Chladni in 1794 formed an epoch in the study of meteorites. This philosopher, still better known by his admirable mode of demonstrating the vibrations and quiescent lines which enter into the phenomena of sound, was the first to collect all the authentic instances of aerolites : a catalogue much enlarged since, but very valuable at the time, and showing great zeal of research. Until this moment scarcely one man of science had given assent to, or even considered the subject as a matter of evidence. The speculations of Kepler, Halley, Maskelyne, and others, as to meteoric matters in the planetary space, scarcely touched upon the history or theory of meteoric stones. Yet it would seem a case where history had some claim to credit, since the facts were of a nature which imagination or fear could hardly mystify or distort. Meteors seen and heard to explode-stones at the same time falling to the earth, and frequently discovered and examined at the time of

local traditions, as we have noticed above. Such traditions, even in the outset, should be sedulously sought for; the manner of doing which most effectively must be determined at the time and place. We will add further that the autumnal months should be avoided, as the malaria fever is rife at this season on the shores of the Dardanelles.

We could hardly hope to recover any remnant of the great stone which was seen to fall at Narni, A.D. 921, and is described as projecting four feet above the water of the river into which it fell.

* The observations from the seventh century before Christ to 960 were derived by M. Biot from the work of Ma-touan-lin, an eminent Chinese author towards tbe end of the 13th century. Those of the three centuries succeeding A.D. 960 come under the anvals of the dynasty of Soung, which during this perioil lad dominion in China.

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