THE ERODING POWER OF ICE.—A paper by Dr. J. S. Newberry, discussing the reality of a glacial period, and the importance of glaciers as geological agents. Glacial Topography, Drift Deposits. Excavation of Lake Basins, Mode of Glacial Erosion. Contained in Scientific American Supplement, No. 499. Price 10 cents. To be had at this office and from all newsdealers.
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