Ragnarok : the Age of Fire and Gravel. Ignatius Donnelly

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      [1. "Edinburgh Review," October, 1874, p. 210.]

      {p. 67}

      If the comet shines by reflected light, it is pretty good evidence that there must be some material substance there to reflect the light.

      "A considerable portion of the light of the comet is, nevertheless, borrowed from the sun, for it has one property belonging to it that only reflected light can manifest. It is capable of being polarized by prisms of double-refracting spar. Polarization of this character is only possible when the light that is operated upon has already been reflected from an imperfectly transparent medium."[1]

      There is considerable difference of opinion as to whether the bead of the comet is solid matter or inflammable gas.

      "There is nearly always a point of superior brilliancy perceptible in the comet's head, which is termed its nucleus, and it is necessarily a matter of pressing interest to determine what this bright nucleus is; whether it is really a kernel of hard, solid substance, or merely a whiff of somewhat more condensed vapor. Newton, from the first, maintained that the comet is made partly of solid substance, and partly of an investment of thin, elastic vapors. If this is the case, it is manifest that the central nodule of dense substance should be capable of intercepting light when it passes in front of a more distant luminary, such as a fixed star. Comets, on this account, have been watched very narrowly whenever they have been making such a passage. On August 18, 1774, the astronomer Messier believed that he saw a second bright star burst into sight from behind the nucleus of a comet which had concealed it the instant before. Another observer, Wartmann, in the year 1828, noticed that the light of an eighth-magnitude star was temporarily quenched as the nucleus of Encke's comet passed over it."[2]

      Others, again, have held that stars have been seen through the comet's nucleus.

      [1. "Edinburgh Review," October, 1874, p. 207.

      2. Ibid., p. 206.]

      {p. 68}

      Amédée Guillemin says:

      "Comets have been observed whose heads, instead of being nebulous, have presented the appearance of stars, with which, indeed, they have been confounded."[1]

      When Sir William Herschel discovered the planet Urania, he thought it was a comet.

      Mr. Richard A. Proctor says:

      "The spectroscopic observations made by Mr. Huggins on the light of three comets show that a certain portion, at least, of the light of these objects is inherent. … The nucleus gave in each case three bands of light, indicating that the substances of the nuclei consisted of glowing vapor."[2]

      In one case, the comet-head seemed, as in the case of the, comet examined by Padre Secchi, to consist of pure carbon.

      In the great work of Dr. H. Schellen, of Cologne, annotated by Professor Huggins, we read:

      "That the nucleus of a comet can not be in itself a dark and solid body, such as the planets are, is proved by its great transparency; but this does not preclude the possibility of its consisting of innumerable solid particles separated from one another, which, when illuminated by the sun, give, by the reflection of the solar light, the impression of a homogeneous mass. It has, therefore, been concluded that comets are either composed of a substance which, like gas in a state of extreme rarefaction, is perfectly transparent, or of small solid particles individually separated by intervening spaces through which the light of a star can pass without obstruction, and which, held together by mutual attraction, as well as by gravitation toward a denser central conglomeration, moves through space like a cloud of dust. In any case the connection lately noticed by Schiaparelli, between comets and meteoric

      [1. "The Heavens," p. 239.

      2. Note to Guillemin's "Heavens," p. 261.]

      {p. 69}

      showers, seems to necessitate the supposition that in many comets a similar aggregation of particles seems to exist."[1]

      I can not better sum up the latest results of research than by giving Dr. Schellen's words in the work just cited:

      "By collating these various phenomena, the conviction can scarcely be resisted that the nuclei of comets not only emit their own light, which is that of a glowing gas, but also, together with the coma and the tail, reflect the light of the sun. There seems nothing, therefore, to contradict the theory that the mass of a comet may be composed of minute solid bodies, kept apart one from another in the same way as the infinitesimal particles forming a cloud of dust or smoke are held loosely together, and that, as the comet approaches the sun, the most easily fusible constituents of these small bodies become wholly or partially vaporized, and in a condition of white heat overtake the remaining solid particles, and surround the nucleus in a self-luminous cloud of glowing vapor."[2]

      Here, then, we have the comet:

      First, a more or less solid nucleus, on fire, blazing, glowing.

      Second, vast masses of gas heated to a white heat and enveloping the nucleus, and constituting the luminous head, which was in one case fifty times as large as the moon.

      Third, solid materials, constituting the tail (possibly the nucleus also), which are ponderable, which reflect the sun's light, and are carried along under the influence of the nucleus of the comet.

      Fourth, possibly in the rear of all these, attenuated volumes of gas, prolonging the tail for great distances.

      What are these solid materials?

      [1. "Spectrum Analysis," 1872.

      2. Ibid., p. 402.]

      {p. 70}

      Stones, and sand, the finely comminuted particles of stones ground off by ceaseless attrition.

      What is the proof of this?

      Simply this: that it is now conceded that meteoric showers are shreds and patches of cometic matter, dropped from the tail; and meteoric showers are stones.

      "Schiaparelli considers meteors to be dispersed portions of the comet's original substance; that is, of the substance with which the comet entered the solar domain. Thus comets would come to be regarded as consisting of a multitude of relatively minute masses."[1]

      Now, what is the genesis of a comet? How did it come to be? How was it born?

      In the first place, there are many things which would connect them with our planets.

      They belong to the solar system; they revolve around the sun.

      Says Amédée Guillemin:

      "Comets form a part of our solar system. Like the. planets, they revolve about the sun, traversing with very variable velocities extremely elongated orbits."[2]

      We shall see reason to believe that they contain the same kinds of substances of which the planets are composed.

      Their orbits seem to be reminiscences of former planetary conditions:

      "All the comets, having a СКАЧАТЬ