Ragnarok: The Age of Fire and Gravel | Page 8

us, on page 307 of the same work, the
above representation of a "terminal moraine."
The reader can see at once that these semicircular
[1. "Geological Sketches," p. 308.]

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ridges bear no resemblance whatever to the great drift-deposits of the
world, spread out in vast and nearly uniform sheets, without
stratification, over hills and plains alike.
And here is another perplexity: It might naturally be supposed that the
smoothed, scratched, and smashed appearance of the underlying rocks
was due to the rubbing and rolling of the stones under the ice of the
glaciers; but, strange to say, we find that--
"The scratched and polished rock-surfaces are by no means confined to
till-covered districts. They are met with everywhere and at all levels
throughout the country, from the sea-coast up to near the tops of some
of our higher mountains. The lower hill-ranges, such as the Sidlaws, the
Ochils, the Pentlands, the Kilbarchan and Paisley Hills, and others,
exhibit polished and smoothed rock-surfaces on their very crest.
Similar markings streak and score the rocks up to a great height in the
deep valleys of the Highlands."[1]
We can realize, in our imagination, the glacier of the mountain-valley
crushing and marking the bed in which it moves, or even the plain on
which it discharges itself; but it is impossible to conceive of a glacier
upon the bare top of a mountain, without walls to restrain it or direct its
flow, or higher ice accumulations to feed it.
Again:
"If glaciers descended, as they did, on both sides of the great Alpine
ranges, then we would expect to find the same results on the plains of
Northern Italy that present themselves on the low grounds of
Switzerland. But this is not the case. On the plains of Italy there are no
traces of the stony clay found in Switzerland and all over Europe.
Neither are any of the stones of the drift of Italy scratched or
striated."[2]
[1. "The Great Ice Age," p. 73.

2. Ibid., pp. 491, 492.]
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But, strange to say, while, as Geikie admits, no true "till" or Drift is
now being formed by or under the glaciers of Switzerland, nevertheless
"till" is found in that country disassociated from the glaciers. Geikie
says:
"In the low grounds of Switzerland we get a dark, tough clay, packed
with scratched and well-rubbed stones, and containing here and there
some admixture of sand and irregular beds and patches of earthy gravel.
This clay is quite unstratified, and the strata upon which it rests
frequently exhibit much confusion, being turned up on end and bent
over, exactly as in this country the rocks are sometimes broken and
disturbed below till. The whole deposit has experienced much
denudation, but even yet it covers considerable areas, and attains a
thickness varying from a few feet up to not less than thirty feet in
thickness."[1]
Here, then, are the objections to this theory of the glacier-origin of the
Drift:
I. The glaciers do not produce striated stones.
II. The glaciers do not produce drift-clay.
III. The glaciers could not have formed continental sheets of "till."
IV. The glaciers could not have existed upon, and consequently could
not have striated, the mountain-tops.
V. The glaciers could not have reached to the great plains of the
continents far remote from valleys, where we still find the Drift and
drift-markings.
VI. The glaciers are limited in number and confined in their operations,
and were utterly inadequate to have produced the thousands of square

miles of drift-_débris_ which we find enfolding the world.
[1. "The Great Ice Age," p. 373.]
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CHAPTER VI.
WAS IT CAUSED BY CONTINENTAL ICE-SHEETS?
WE, come now to the theory which is at present most generally
accepted:
It being apparent that glaciers were not adequate to produce the results
which we find, the glacialists have fallen back upon an extraordinary
hypothesis--to wit, that the whole north and south regions of the globe,
extending from the poles to 35° or 40° of north and south latitude, were,
in the Drift age, covered with enormous, continuous sheets of ice, from
one mile thick at its southern margin, to three or five miles thick at the
poles. As they find drift-scratches upon the tops of mountains in
Europe three to four thousand feet high, and in New England upon
elevations six thousand feet high, it follows, according to this
hypothesis, that the ice-sheet must have been considerably higher than
these mountains, for the ice must have been thick enough to cover their
tops, and high enough and heavy enough above their tops to press
down upon and groove and scratch the rocks. And as the _striæ_ in
Northern Europe were found to disregard the conformation of the
continent and the islands of the sea,