Prof. Aggassiz [sic], in the Atlantic Monthly, advances the theory that the continent of North America was at one time covered with ice, a mile in thickness. The proof is, that the slopes of the Alleghany range of mountains are glacier worn, to the very tops, except a few points which were above the level of the icy mass. Mount Washington, for instance, is over six thousand feet high, and the rough, unpolished surface of its summit, covered with loose fragments, just below the level of which, glacier marks come to an end, tells us that it lifted its head alone above the desolate waste of ice and snow. In this region then, the thickness of the sheet could not have been much less than six thousand feet; and this is in keeping with the same kind of evidence in other parts of the country, for whenever the mountains are much below six thousand feet, the ice seems to have passed directly over them, while the few peaks arising to that height are left untouched. The glacier, he argued, was God’s great plow, and when the ice vanished from the face of the land, it left it prepared for the hand of the husbandman. The hard surface of the rocks was ground to powder. The elements of the soil were mingled in fair proportions; granite was carried into lime regions; lime was mingled with the more arid and unproductive granite districts, and a soil was prepared for the agricultural uses of man. There are evidences all over the polar regions to show that at one period the heat of the tropic extended all over the globe. The ice period is supposed to be long subsequent to this, and next to the last before the advent of man.
– Published in the Stark County News, Toulon, Illinois, Thursday, August 11, 1864
– Published in the Stark County News, Toulon, Illinois, Thursday, August 11, 1864
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