The Ice Age in North America and Its Bearings Upon the Antiquity of Man

accumulation American Journal amount basin bowlders channel coast continuous Creek Croll depression depth distance drainage drift drumlins earth's east eastern elevation erosion evidence extended facts feet above tide feet high formed Fort Snelling Geological Survey geologists glacial boundary glacial débris glacial deposits Glacial epoch Glacial period glaciated area glaciated region glacier gorge gravel Greenland height hills hundred feet Ice age ice-front ice-sheet icebergs implements inlet Island Journal of Science kames kettle-holes Kittatinny Mountain Lake Agassiz Lake Erie latitude Little Falls loess lower margin marked mass melting miles Minnesota Mississippi mountains movement Muir Glacier Muir Inlet North America northern numerous Ohio Ohio River palæolithic pebbles Pliocene portion preglacial present Professor Report ridges River rock Rocky sand shore side slope southern streams striæ subglacial summit surface terminal moraine terraces theory thickness thousand feet tion Trenton Upham upper valley vicinity