Ragnarok : the Age of Fire and Gravel. Ignatius Donnelly

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СКАЧАТЬ the Drift ref used to enter Asia out of respect to the geographical lines.

      But not alone is the Drift absent from Siberia, and, probably, all Asia; it does not extend even over all Europe. Louis Figuier says that the traces of glacial action "are observed in all the north of Europe, in Russia, Iceland, Norway, Prussia, the British Islands, part of Germany in the north, and even in some parts of the south of Spain."[2] M. Edouard Collomb finds only a "a shred" of the glacial evidences in France, and thinks they were absent from part of Russia!

      [1. "The Great Ice Age," p. 461.

      2. "The World before the Deluge," p. 451.]

      {p. 31}

      And, even in North America, the Drift is not found everywhere. There is a remarkable region, embracing a large area in Wisconsin, Iowa, and Minnesota, which Professor J. D. Whitney[1] calls "the driftless region," in which no drift, no clays, no gravel, no rock strive or furrows are found. The rock-surfaces have not been ground down and polished. "This is the more remarkable," says Geikie, "seeing that the regions to the north, west, east, and south are all more or less deeply covered with drift-deposits."[2] And, in this region, as in Siberia, the remains of the large, extinct mammalia are found imbedded in the surface-wash, or in cracks or crevices of the limestone.

      If the Drift of North America was due to the ice-sheet, why is there no drift-deposit in "the driftless region" of the Northwestern States of America? Surely this region must have been as cold as Illinois, Ohio, etc. It is now the coldest part of the Union. Why should the ice have left this oasis, and refused to form on it? Or why, if it did form on it, did it refuse to tear up the rock-surfaces and form Drift?

      Again, no traces of northern drift are found in California, which is surrounded by high mountains, in some of which fragments of glaciers are found even to this day.[3]

      According to Foster, the Drift did not extend to Oregon; and, in the opinion of some, it does not reach much beyond the western boundary of Iowa.

      Nor can it be supposed that the driftless regions of Siberia, Northwestern America, and the Pacific coast are due to the absence of ice upon them during the Glacial

      [1. "Report of the Geological Survey of Wisconsin," vol. i, p. 114.

      2. "The Great Ice Age," p. 465.

      3. Whitney, "Proceedings of the California Academy of Natural Sciences."]

      {p. 32}

      age, for in Siberia the remains of the great mammalia, the mammoth, the woolly rhinoceros, the bison, and the horse, are found to this day imbedded in great masses of ice, which, as we shall see, are supposed to have been formed around them at the very coming of the Drift age.

      But there is another difficulty:

      Let us suppose that on all the continents an ice-belt came down from the north and south poles to 35° or 40° of latitude, and there stood, massive and terrible, like the ice-sheet of Greenland, frowning over the remnant of the world, and giving out continually fogs, snow-storms, and tempests; what, under such circumstances, must have been the climatic conditions of the narrow belt of land which these ice-sheets did not cover?

      Louis Figuier says:

      "Such masses of ice could only have covered the earth when the temperature of the air was lowered at least some degrees below zero. But organic life is incompatible with such a temperature; and to this cause must we attribute the disappearance of certain species of animals and plants--in particular the rhinoceros and the elephant--which, before this sudden and extraordinary cooling of the globe, appeared to have limited themselves, in immense herds, to Northern Europe, and chiefly to Siberia, where their remains have been found in such prodigious quantities."[1]

      But if the now temperate region of Europe and America was subject to a degree of cold great enough to destroy these huge animals, then there could not have been a tropical climate anywhere on the globe. If the line of 35° or 40°, north and south, was several degrees below zero, the equator must have been at least below the frost-point. And, if so, how can we account for the survival,

      [1. "The World before the Deluge," p. 462.]

      {p. 33}

      to our own time, of innumerable tropical plants that can not stand for one instant the breath of frost, and whose fossilized remains are found in the rocks prior to the Drift? As they lived through the Glacial age, it could not have been a period of great and intense cold. And this conclusion is in accordance with the results of the latest researches of the scientists:--

      "In his valuable studies upon the diluvial flora, Count Gaston de Saporta concludes that the climate in this period was marked rather by extreme moisture than extreme cold."

      Again: where did the clay, which is deposited in such gigantic masses, hundreds of feet thick, over the continents, come from? We have seen (p. 18, ante) that, according to Mr. Dawkins, "no such clay has been proved to have been formed, either in the Arctic regions, whence the ice-sheet has retreated, or in the districts forsaken by the glaciers."

      If the Arctic ice-sheet does not create such a clay now, why did it create it centuries ago on the plains of England or Illinois?

      The other day I traveled from Minnesota to Cape May, on the shore of the Atlantic, a distance of about fifteen hundred miles. At scarcely any point was I out of sight of the red clay and gravel of the Drift: it loomed up amid the beach-sands of New Jersey; it was laid bare by railroad-cuts in the plains of New York and Pennsylvania; it covered the highest tops of the Alleghanies at Altoona; the farmers of Ohio, Indiana, Illinois, and Wisconsin were raising crops upon it; it was everywhere. If one had laid down a handful of the Wisconsin Drift alongside of a handful of the New Jersey deposit, he could scarcely have perceived any difference between them.

      {p. 34}

      Here, then, is a geological formation, almost identical in character, fifteen hundred miles long from east to west, and reaching through the whole length of North and South America, from the Arctic Circle to Patagonia.

      Did ice grind this out of the granite?

      Where did it get the granite? The granite reaches the surface only in limited areas; as a rule, it is buried many miles in depth under the sedimentary rocks.

      How did the ice pick out its materials so as to grind nothing but granite?

      This deposit overlies limestone and sandstone. The ice-sheet rested upon them. Why were they not ground up with the granite? Did the ice intelligently pick out a particular kind of rock, and that the hardest of them all?

      But here is another marvel--this clay is red. The red is due to the grinding up of mica and hornblende. Granite is composed of quartz, feldspar, and mica. In syenitic granite the materials are quartz, feldspar, and hornblende. Mica and hornblende contain considerable oxide of iron, while feldspar has none. When mica and hornblende are ground up, the result is blue or red clays, as the oxidation of the iron turns the clay red; while the clay made of feldspar is light yellow or white.

      Now, then, not only did the ice-sheet select for grinding the granite rocks, and refuse to touch the others, but it put the granite itself through some mysterious process by which it separated the feldspar from the mica and hornblende, and manufactured a white or yellow clay out of the one, which it deposited in great sheets by itself, as west of the Mississippi; while it ground up the mica and hornblende and made СКАЧАТЬ