Cosmos: A Sketch of the Physical Description of the Universe Part 11

[footnote] *From a letter to myself, dated Jan. 24th, 1838. The enormous swarm of falling stars in November, 1799, was almost exclusively seen in America, where it was witnessed from New Herrnhut in Greenland to the equator. The swarms of 1831 and 1832 were visible only in Europe, and those of 1833 and 1834 only in the United States of North America.

If the hypothesis of a regular progression or oscillation of the nodes should acquire greater weight, special interest will be attached to the investigation of older observations. The Chinese annals, in which great falls of shooting stars, as well as the phenomena of comets, are recorded, go back beyond the age of Tyrts, or the second Messenian war. They give a description of two streams in the month of March, one of which is 687 years anterior to the Christian era. Edward Biot has observed that among the fifty-two phenomena which he has collected from the Chinese annals, those that were of most frequent recurrence are recorded at periods nearly corresponding with the 20th and 22d of July, O.S., and might consequently be identical with the stream of St. Lawrence's day, taking into account that it has advanced since the epochs* indicated.

[footnote] *Lettre de M. Edouard Biot ? M. Quetelet, sur les anciennes apparitions d'Etoiles Filantes en Chine, in the 'Bull. de l'Acad?mie de Bruxelles', 1843, t. x., No. 7, p. 8. On the notice from the 'Chronicon Ecclesi Pragensis', see the younger Boguslawski, in Poggend., 'Annalen', bd. xlviii., s. 612.

If the fall of shooting stars of the 21st of October, 1366, O.S. (a notice of which was found by the younger Von Boguslawski, in Benessius de Horowic's 'Chronicon Ecclesi Pragensis'), be identical with our November phenomenon, although the occurrence in the fourteenth century was seen in broad daylight, we find by the precession in 477 years that this system of meteors, or, rather, its common center of gravity, must describe p 129 a retrograde orbit round the Sun. It also follows, from the views thus developed, that the non-appearance, during certain years, in any portion of the Earth, of the two streams. .h.i.therto observed in November and about the time of St. Lawrence's day, must be ascribed either to an interruption in the meteoric ring, that is to say, to intervals occurring between the asteroid groups, or, according to Poisson to the action of the larger planets* on the form and position of this annulus.

[footnote] *"It appears that an apparently inexhaustible number of bodies, too small to be observed, are moving in the regions of s.p.a.ce, either around the Sun or the planets, or perhaps even around their satellites. It is supposed that when these bodies come in contact with our atmosphere, the difference between their velocity and that of our planet is so great, that the friction which they experience from their contact with the air heats them to incandescence, and sometimes causes their explosion. If the group of falling stars form an annulus around the Sun, its velocity of circulation may be very different from that of our Earth; and the displacements it may experience in s.p.a.ce, in consequence of the actions of the various planets, may render the phenomenon of its intersecting the planes of the ecliptic possible at some epochs, and altogether impossible at others." -- Poisson, 'Recherches sur la Probabilit? des Jugements', p. 306, 307.

The solid ma.s.ses which are observed by night to fall to the earth from fire-b.a.l.l.s, and by day generally when the sky is clear, from a cark small cloud, are accompanied by much candescence. They undeniably exhibit a great degree of general ident.i.ty with respect to their external form, the character of their crust, and the chemical composition of their princ.i.p.al const.i.tuents. These characteristics of ident.i.ty have been observed at all the different epochs and in the most various parts of the earth in which these meteoric stones have been found. This striking and early-observed a.n.a.logy of physiognomy in the denser meteoric ma.s.ses is, however, met by many exceptions regarding individual points. What differences, for instance, do we not find between the malleable ma.s.ses of for instance, do we not find between the malleable ma.s.ses of iron of Hradeschina in the district of Agram, those from the sh.o.r.es of the Sisim in the government of Jeniseisk, rendered so celebrated by Pallas, or those which I brought from Mexico,* all of which contain 96 per cent. of iron, from the a?rolites of Siena, in which the iron scarcely amounts to 2 per cent., or the earthy a?rolite of Alais (in the Department du Gard), which broke up in water, or, lastly, from those of Jonzac and Javenas, which contained no metallic iron, but presented a p 130 mixture of oryctognostically distinct crystalline compoonents!

[footnote] *Humboldt, 'Essai Politique sur la Nouv. Espagne' (2de ?dit.), t. iii. p. 310.

These differences have led mineralogists to separate these cosmical ma.s.ses into two cla.s.ses, namely, those containing nickelliferous meteoric iron, and those consisting of fine or coa.r.s.ely-granular meteoric dust. The crust or rind of a?rolites is peculiarly characteristic of these bodies, being only a few tenths of a line in thickness, often glossy and pitch-like, and occasionally veined.*

[footnote] *The peculiar color of their crust was observed even as early as in the time of Pliny (ii., 56 and 58): "colore adusto." The phrase "lateribus pluisse" seems also to refer to the burned outer surface of a?rolites.

There is only one instance on record, as far as I am aware (the a?rolite of Chantonnay, in La Vend?e), in which the rind was absent, and this meteor, like that of Juvenas, presented likewise the peculiarity of having pores and vesicular cavities. In all other cases the black crust is divided from the inner light-gray ma.s.s by as sharply-defined a line of separation as is the black leaden-colored investment of the white granit blocks* which I brought from the cataracts of the Orinoco, and which are also a.s.sociated with many other cataracts, as, for instance, those of the Nile and of the Congo River.

[footnote] * Humb., 'Rel. Hist.', t. ii., chap xx., p. 299-302.

The greatest heat employed in our porcelain ovens would be insufficient to produce any thing similar to the crust of meteoric stones, whose interior remains wholly unchanged. Here and there, facts have been observed which would seem to indicate a fusion together of the meteoric fragments; but, in general, the character of the aggregate ma.s.s, the absence of compression by the fall, and the inconsiderable degree of heat possessed by these bodies when they reach the earth, are all opposed to the hypothesis of the interior being in a state of fusion during their short pa.s.sage from the boundary of the atmosphere to our Earth.

The chemical elements of which these meteoric ma.s.ses consist, and on which Berzelius has thrown so much light, are the same as those distributed throughout the earth's crust, and are fifteen in number, namely, iron, nickel, cobalt, manganese, chromium, copper, a.r.s.enic, zinc, potash, soda, sulphur, phosphorus, and carbon, const.i.tuting altogether nearly one third of all the known simple bodies. Notwithstanding this similarity with the primary elements into which inorganic bodies are chemically reducible, the aspect of a?rolites, owing to the mode in which their const.i.tuent parts are compounded, presents, generally, some features foreign to our telluric rocks and minerals. The pure native iron, which is almost always p 131 found incorporated with a?rolites, imparts to them a peculiar, but not consequently, a 'selenic' character; for in other regions of s.p.a.ce, and in other cosmical bodies besides our Moon, water may be wholly absent, and processes of oxydation of rare occurence.

Cosmical gelatinous vesicles, similar to the organic 'nostoc' (ma.s.ses which have been supposed since the Middle Ages to be connected with shooting stars), and those pyrites of Sterlitamak, west of the Uralian Mountains, which are said to have const.i.tuted the interior of hailstones,* must both be cla.s.sed among the mythical fables of meteorology.

[footnote] *Gustav Rose, 'Reise nach dem Ural', bd. II., s. 202.

Some few a?rolites, as those composed of a finely granular tissue of olivine, augite, and labradorite blended together* (as the meteoric stone found at Juvenas, in the Department de l'Ardche, which resembled dolorite), are the only ones, as Gustav Rose has remarked, which have a more familiar aspect.

[footnote] *Gustav Rose, in Poggend., 'Ann.', 1825, bd. iv., x. 173-192.

Rammelsberg, 'Erstes Suppl. zum chem. Handw?rterbuche der Mineralogie', 1843, s. 102. "It is," says the clear-minded observer Olbers, "a remarkable but hitherto unregarded fact, that while sh.e.l.ls are found in secondary and tertiary formations, no 'fossil meteoric stones' have as yet been discovered. May we conclude from this circ.u.mstance that previous to the present and last modification of the earth's surface no meteoric stones fell on it, although at the present time it appears probable, from the researches of Schreibers, that 700 fall annually?" (Olbers, in Schum., 'Jahrb.', 1838, s. 329.) Problematical nickelliferous ma.s.ses of native iron have been found in Northern Asia (at the gold-was.h.i.+ng establishment at Petropawlowsk, eighty miles southeast of Kusnezk), imbedded thirty-one feet in the ground, and more recently in the Western Carpathians (the mountain chain of Magura, at Szlanicz), both of which are remarkably like meteoric stones. Compart Erman, 'Archiv f?r wissenschaftliche Kunde von Russland', bd. i., s. 315, and Haidinger, 'Bericht ?ber Szlaniczer Sch?rfe in Ungarn.'

These bodiescontain, for instance, crystalline substances, perfectly similar to those of our earth's crust; and in the Siberian ma.s.s of meteoric iron investigated by Pallas, the olivine only differs from common olivine by the absence of nickel, which is replaced by the oxyd of tin.*

[footnote] *Berzelius, 'Jahresber.', bd. xv., s. 217 und 231. Rammelsberg, 'Handw?rterb., abth. ii., s. 25-28.

As meteoric olivine, like our basalt, contains from 47 to 49 per cent. of magnesia, const.i.tuting, according to Berzelius, almost the half of the earthy components of meteoric stones, we can not be surprised at the great quant.i.ty of silicate of magnesia found in these cosmical bodies. If the z?rolite of Juvenas contain separable crystals of augite and labradorite, the numerical relation of the const.i.tuents p 132 render it at least probable that the meteoric ma.s.ses of Chateau-Renard may be a compound of diorite, consisting of hornblende and albite, and those of Blansko and Chantonnay compounds of hornblende and labradorite. The proofs of the telluric and atmospheric origin of aUerolites, which it is attempted to base upon the oryctognostic a.n.a.logies presented by these bodies, do not appear to me to possess any great weight.

Recalling to mind the remarkable interview between Newton and Conduit at Kensington,* I would ask why the elementary substances that compose one group of cosmical bodies, or one planetary system, may not, in a great measure, be identical?

[footnote] * "Sir Isaac Newton said he took all the planets to be composed of the same matter with the Earth, viz., earth, water, and stone, but variously connected." -- Turner, 'Collections for the History of Grantham, containing authentic Memoirs of Sir Isaac Newton', p. 172.

Why should we not adopt this view, since we may conjecture that these planetary bodies, like all the larger or smaller agglomerated ma.s.ses revolving round the sun, have been thrown off from the once far more expanded solar atmosphere, and been formed from vaporous rintgs describing their orbits round the central body? We are not, it appears to me, more justified in applying the term telluric to the nickel and iron, the olivine and pyroxene (augite), found in meteoric stones, than in indicating the German plants which I found beyond the Obi as European species of the flora of Northern Asia. If the elementary substances composing a group of cosmical bodies of different magnitudes be identical, why should they not likewise, in obeying the laws of mutual attraction, blend together under definite relations of mixture, composing the white glittring snow and ice in the polar zones of the planet Mars, or const.i.tuting in the smaller cosmical ma.s.ses mineral bodies inclosing crystals of olivine, augite, and labradorite? Even in the domain of pure conjecture we should not suffer ourselves to be led away by unphilosophical and arbitrary views devoid of the support of inductive reasoning.

Remarkable obscurations of the sun's disk, during which the stars have been seen at mid-day (as, for instance, in the obscuration of 1547, which continued for three days, and occurred about the time of the eventful battle of M?hlberg), can not be explained as arising from volcanic ashes or mists, and were regarded by Kepler as owing either to a 'materia cometica', or to a black cloud formed by the sooty exhalations of the solar body. The shorter obscurations of 1090 and 1203, which continued, the one only three, and the other six p 133 hours, were supposed by Chladni and Schnurrer to be occasioned by the pa.s.sage of meteoric ma.s.ses before the sun's disk. Since the period that streams of meteoric shooting stars were first considered with reference to the direction of their orbit as a closed ring, the epochs of these mysterious celestial phenomena have been observed to present a remarkable connection with the regular recurrence of swarms of shooting stars Adolph Erman has evinced great acuteness of mind in his accurate investigation of the facts. .h.i.therto observed on this subject, and his researches have enabled him to discover the connection of the sun's conjunction with the August asteroids on the 7th of February, and with the November asteroids on the 12th of May, the latter period corresponding with the days of St. Mamert (May 11th), St. Pancras (May 12th), and St. Servatius (May 13th), which according to popular belief, were accounted "cold days."*

[footnote] Adolph Erman, in Poggend., 'Annalen', 1839, bd. xlviii., s.

582-601. Biot had previously thrown doubt regarding the probability of the November stream reappearing in the beginning of May ('Comptes Rendus', 1836, t. ii., p. 670). M?dler has examined the mean depression of temperature on the three ill-named days of May by Berlin observations for eighty-six years ('Verhandl. des Vereins zur Bedf?rd, des Gartenbaues', 1834, s. 377), and found a retrogression of temperature amounting to 2.2 degrees Fahr. from the 11th to the 13th of May, a period at which nearly the most rapid advance of heat takes place. It is much to be desired that this phenomenon of depressed temperature, which some have felt inclined to attribute to the melting of the ice in the northeast of Europe, should be also investigated in very remote spots, as in America, or in the southern hemisphere. (Comp.

'Bull. de l'Acad. Imp. de St. P?tersbourg', 1843, t. i., No. 4.)

The Greek natural philosophers, who were but little disposed to pursue observations, but evinced inexhaustible fergility of imagination in giving the most various interpretation of half-perceived facts, have, however, left some hypotheses regarding shooting stars and meteoric stones which strikingly accord with the views now almost universally admitted of the cosmical process of these phenomena. "Falling stars," says Plutarch, in his life of Lysander,* are, according to the opinion of some physicists, not eruptions of the ethereal fire extinguished in the air immediately after its ignition, nor yet an inflammatory combustion of the air, which is dissolved in large quant.i.ties in the upper regions of s.p.a.ce, but these meteors are rather a fall of celestial bodies, which, in consequence of a certain intermission in the rotatory force, and by the impulse of some irregular movements, have been hurled down not only to the inhabited portions of the Earth, but also beyond it into the great ocean, where we can not find them."

[footnote] *Plut., 'Vit par, in Lysandro', cap. 22. The statement of Damachos (Da?machos), that for seventy days continuously there was a fiery cloud seen in the sky, emitting sparks like falling stars, and which then, sinking nearer to the earth, let fall the stone of gos Potamos, "which, however, was only a small part of it," is extremely improbable, since the direction and velocity of the fire-cloud would in that case of necessity have to remain for so many days the same as those of the earth; and this, in the fire-ball of the 19th of July, 1686, described by Halley ('Trans.', vol.

xxix., p. 163), lasted only a few minutes. It is not altogether certain whether Da?machos, the writer, [Greek words], was the same person as Da?machos of Plata, who was sent by Selencus to India to the son of Androcottos, and who ws charged by Strabo with being "a speaker of lies" (p.

70, Casaub.). From another pa.s.sage of Plutarch ('Compar. Solonis c. Cop.', cap. 5) we should almost believe that he was. At all events, we have here only the evidence of a very late author, who wrote a century and a half after the fall of a?rolites occurred in Thrace, and whose authenticity is also doubted by Plutarch.

Diogenes of Apollonia* expresses himself still more explicitly.

[footnote] *Stob., ed. Heeren, i., 25, p. 508; Plut., 'de plac. Philos.', ii., 13.

According to his views, "Stars that are 'invisible', and, consequently, have no name, move in s.p.a.ce together with those that are visible. These invisible stars frequently fall burning at gos Potamos." The Apollonian, who held all other stellar bodies, when luminous, to be of a pumice-like nature, probably grounded his opinions regarding shooting stars and meteoric ma.s.ses on the doctrine of Anaxagoras the Clazomenian, who regarded all the bodies in the universe "as fragments of rocks, which the fiery ether, in the force of its gyratory motion, had torn from the Earth and converted into stars." In the Ionian school, therefore, according to the testimony transmitted to us in the views of Diogenes of Apollonia, a?rolites and stars were ranged in one and the same cla.s.s; both, when considered with reference to their primary origin, being equally telluric, this being understood only so far as the Earth was then regarded as a central body,*

p 135 forming all things around it in the same manner was we, according to our present views, suppose the planets of our system to have originated in the expanded atmosphere of another central body, the Sun.

[footnote] *The remarkable pa.s.sage in Plut., 'de plac. Philos.', ii., 13, runs thus: "Anaxagoras teaches that the surrounding ether is a fiety substance, which, by the power of its rotation, tears rocks from the earth, inflames them, and converts them into stars." Applying an ancient fable to ill.u.s.trate a physical dogma, the Clazomenian appears to have ascribed the fall of the Neman Lion to the Peloponnesus from the Moon to such a rotatory or centrifugal force. (lian., xii., 7; Plut., 'de Facie in Orge Lun' c. 24; Schol. ex Cod. Paris., in 'Apoll. Argon.', lib. i., p. 498, ed. Schaef., t. ii., p. 40; Meineke, 'Annal. Alex.', 1843, p. 85.) Here, instead of stones from the Moon, we have an animal from the Moon! According to an acute remark of B?ckh, the ancient mythology of the Neman lunar lion has an astronomical origin, and is symbolically connected in chronology with the cycle of intercalation of the lunar year, with the moon-wors.h.i.+p at Nema, and the games by which it was accompanied.

These views must not, therefore, be confounded with what is commonly termed the telluric or atmospheric origin of meteoric stones, nor yet with the singular opinion of Aristotle, which supposed the enormous ma.s.s of gos Potamos to have been raised by a hurricane. That rrogant spirit of incredulity, which rejects facts without attempting to investigate them, is in some cases almost more injurious than an unquestioning credulity. Both are alike detrimental to the force of investigation. Notwithstanding that for more than two thousand years the annals of different nations had recorded falls of meteoric stones, many of which had been attested beyond all doubt by the evidence of irreproachable eye-witnesses -- notwithstanding the important part enacted by the Btylia in the meteor-wors.h.i.+p of the ancients -- notwithstanding the fact of the companions of Cortez having see an a?rolite at Cholula which had fallen on the neighboring pyramid -- notwithstanding that califs and Mongolian chiefs had caused swords to be forged from recently-fallen meteoric stones -- nay, notwithstanding that several persons had been struck dead by stones falling from heaven, as for instance, a monk at Crema on the 4th of September, 1511, another monk at Milan in 1650, and two Swedish sailors on board s.h.i.+p in 1674, yet this great cosmical phenomenon remained almost wholly unheeded, and its intimate connection drawn to the subject by Chladni, who had already gained immortal renown by his discovery of the sound-figures. He who is penetrated with a sense of this mysterious connection, and whose mind is open to deep impressions of nature, will feel himself moved by the deepest and most solemn emotion at the sight of every star that shoots across the vault of heaven, no less than at the glorious spectacle of meteoric swarms in the November phenomenon or on St. Lawrence's day. Here motion is suddenly revealed in the midst of nocturnal rest. The still radiance of the vault of heaven is for a moment animated with life and movement. In the mild radiance left on the track of the shooting star, imagination pictures the lengthened path of the meteor through the vault of heaven, p 136 while, every where around, the luminous asteroids proclaim the existence of one common material universe.

If we compare the volume of the innermost of Saturn's satellites, or that of Ceres, with the immense volume of the Sun, all relations of magnitude vanish from our minds. The extinction of suddenly resplendent stars in Ca.s.siopeia, Cygnus, and Serpentarius have already led to the a.s.sumption of other and non-luminous cosmical bodies. We now know that the meteoric asteroids, spherically agglomerated into small ma.s.ses, revolve round the Sun, intersect, like comets, the orbits of the luminous larger planets, and become ignited either in the vicinity of our atmosphere or in its upper strata.

The only media by which we are brought in connection with other planetary bodies, and with all portions of the universe beyond our atmosphere, are light and heat (the latter of which can scarcely be separated from the former),* and those mysterious powers of attraction exercised by remote ma.s.ses, according to the quant.i.ty of their const.i.tuents, upon our globe, the ocean, and the strata of our atmosphere.