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The Canadian naturalist and geologist (1865)
The Canadian naturalist and geologist - 1865 Author:Unknown Author Purchase of this book includes free trial access to www.million-books.com where you can read more than a million books for free. This is an OCR edition with typos. Excerpt from book: Rhinoceros tichorhinus. Well may we then ask, how is it that the ancient and larger glaciers, which were supposed to have had such enormous excavating power as t... more »o have scooped out deep valleys in hard rocks, should not have entirely destroyed the loose accumulation of gravel over which they have been spread ? Or, if glaciers excavated the Lago di Garda and Lago Maggoire, why did they not produce any such effect at Ivrea, in the Valley of Aosta, down which we know that enormous masses of ice travelled ; or at Rivoli, in their march from Mount Cenis towards Turin ? Leaving it to physical philosophers, such as Forbes, Faraday, Hopkins, and Tyndall, to show what is the real measure of the abrading power of masses of moving ice, I simply form my opinion from what glaciers are accomplishing, or have accomplished. Judging from positive data, I infer that if, as agents, they have been wholly incapable of removing even the old and loose alluvial drift which encumbered the valleys, infinitely less had they the power of excavating hard rocks. At the same time I know that, in every mountain tract which I have examined, there have been quite a sufficient number of rents and denudations to account for all inequalities. These openings have doubtless been greatly increased by the atmospheric agencies of ages, and particularly in all those situations where water has acted with great power, during the melting of glaciers. K Whilst I was reading this Address to the Geographers in London, that sound practical geologist, Principal Dawson, was performing a similar duty at the Annual Meeting of the Natural History Society of Montreal. Having received a copy of his Address in time lor insertion of a Postcript, I am glad to have the opportunity of stating that he also is a vigorous opponent of the t...« less