Ragnarok : the Age of Fire and Gravel. Ignatius Donnelly

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СКАЧАТЬ and the local precipitation of unusual quantities of rain; and the effect of such a catastrophe would be slowly propagated and feebly felt in the Arctic and Antarctic regions.

      When we consider the magnitude of the ice-sheets which, it is claimed by the glacialists, covered the continents during the Drift age, it becomes evident that a vast proportion of the waters of the ocean must have been evaporated and carried into the air, and thence cast down as snow and rain. Mr. Thomas Belt, in a recent number of the "Quarterly Journal of Science," argues that the formation of ice-sheets at the poles must have lowered the level of the oceans of the world two thousand-feet!

      The mathematician can figure it out for himself: Take the area of the continents down to, say, latitude 40°, on both sides of the equator; suppose this area to be covered by an ice-sheet averaging, say, two miles in thickness; reduce this mass of ice to cubic feet of water, and estimate what proportion of the ocean would be required to be vaporized to create it. Calculated upon any basis, and it follows that the level of the ocean must have been greatly lowered.

      What a vast, inconceivable accession of heat to our

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      atmosphere was necessary to lift this gigantic layer of ocean-water out of its bed and into the clouds!

      The ice, then, was not the cause of the cataclysm; it was simply one of the secondary consequences.

      We must look, then, behind the ice-age for some cause that would prodigiously increase the heat of our atmosphere, and, when we have found that, we shall have discovered the cause of the drift-deposits as well as of the ice.

      The solution of the whole stupendous problem is, therefore, heat, not cold.

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      PART II.

      The Comet.

      CHAPTER I.

      A COMET CAUSED THE DRIFT.

      Now, good reader, we have reasoned together up to this point. To be sure, I have done most of the talking, while you have indulged in what the Rev. Sydney Smith called, speaking of Lord Macaulay, "brilliant flashes of silence."

      But I trust we agree thus far that neither water nor ice caused the Drift. Water and ice were doubtless associated with it, but neither produced it.

      What, now, are the elements of the problem to be solved?

      First, we are to find something that instantaneously increased to a vast extent the heat of our planet, vaporized the seas, and furnished material for deluges of rain, and great storms of snow, and accumulations of ice north and south of the equator and in the high mountains.

      Secondly, we are to find something that, coming from above, smashed, pounded, and crushed "as with a maul," and rooted up as with a plow, the gigantic rocks of the surface, and scattered them for hundreds of miles from their original location.

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      Thirdly, we are to find something which brought to the planet vast, incalculable masses of clay and gravel, which did not contain any of the earth's fossils; which, like the witches of Macbeth,

      Look not like th' inhabitants of earth,

       And yet are on it; "

      which are marked after a fashion which can not be found anywhere else on earth; produced in a laboratory which has not yet been discovered on the planet.

      Fourthly, we are to find something that would produce cyclonic convulsions upon a scale for which the ordinary operations of nature furnish us no parallel.

      Fifthly, we are to find some external force so mighty that it would crack the crust of the globe like an eggshell, lining its surface with great rents and seams, through which the molten interior boiled up to the light.

      Would a comet meet all these prerequisites?

      I think it would.

      Let us proceed in regular order.

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      CHAPTER II.

      WHAT IS A COMET?

      IN the first place, are comets composed of solid, liquid, or gaseous substances? Are they something, or the next thing to nothing?

      It has been supposed by some that they are made of the most attenuated gases, so imponderable that if the earth were to pass through one of them we would be unconscious of the contact. Others have imagined them to be mere smoke-wreaths, faint mists, so rarefied that the substance of one a hundred million miles long could, like the genie in the Arabian story, be inclosed in one of Solomon's brass bottles.

      But the results of recent researches contradict these views:

      Padre Secchi, of Rome, observed, in Donati's comet, of 1858, from the 15th to the 22d of October, that the nucleus threw out intermittingly from itself appendages having the form of brilliant, coma-shaped masses of incandescent substance twisted violently backward. He accounts for these very remarkable changes of configuration by the influence first of the sun's heat upon the comet's substance as it approached toward perihelion, and afterward by the production in the luminous emanations thus generated of enormous tides and perturbation derangements. Some of the most conspicuous of these luminous developments occurred on October 11th, when the comet was at its nearest approach to the earth, and on

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      October 17th, when it was nearest to the planet Venus. He has no doubt that the close neighborhood of the earth and Venus at those times was the effective cause of the sudden changes of aspect, and that those changes of aspect may be accepted as proof that the comet's substance consists of "really ponderable material."

      Mr. Lockyer used the spectroscope to analyze the light of Coggia's comet, and he established beyond question that--

      "Some of the rays of the comet were sent either from solid particles, or from vapor in a state of very high condensation, and also that beyond doubt other portions of the comet's light issue from the vapor shining by its own inherent light. The light coming from the more dense constituents, and therefore giving a continuous colored spectrum, was, however, deficient in blue rays, and was most probably emitted by material substance at the low red and yellow stages of incandescence."

      Padre Secchi, at Rome, believed he saw in the comet "carbon, or an oxide of carbon, as the source of the bright luminous bands," and the Abbé Moigno asks whether this comet may not be, after all, "un gigantesque diamant volatilisé."

      "Whatever may be the answer hereafter given to that question, the verdict of the spectroscope is clearly to the effect that the comet is made up of a commingling of thin vapor and of denser particles, either compressed into the condition of solidification, or into some physical state approaching to that condition, and is therefore entirely in accordance with the notion formed on other grounds that the nucleus of the comet is a cluster of solid nodules or granules, and that the luminous coma and tail are jets and jackets of vapor, associated with the more dense ingredients, and swaying and streaming about them as heat and gravity, acting antagonistic ways, determine."[1]

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