The ice age in North America and its bearing upon the antiquity of man5th edwith many new maps and illus., enland rewritten to incorporate the facts that bring it up to date, with chapters on Lake Agassiz and the Probable cause of glaciation . Buffalo. Hence the natural outlet to the Great Lakesthrough the Mohawk Valley would not have been openeduntil the ice-front over New England and eastern New Yorkhad retreated to the north well-nigh one hundred and fiftymiles. A similar amount of retreat of the ice-front fromits farthest extension in Cattaraugus county, in New York,would have carried it b
The ice age in North America and its bearing upon the antiquity of man5th edwith many new maps and illus., enland rewritten to incorporate the facts that bring it up to date, with chapters on Lake Agassiz and the Probable cause of glaciation . Buffalo. Hence the natural outlet to the Great Lakesthrough the Mohawk Valley would not have been openeduntil the ice-front over New England and eastern New Yorkhad retreated to the north well-nigh one hundred and fiftymiles. A similar amount of retreat of the ice-front fromits farthest extension in Cattaraugus county, in New York,would have carried it back thirty miles to the north of LakeOntario, while a similar amount of retreat from eastern Ohiowould have left nearly all the present bed of Lake Erie freefrom glacial ice. With little doubt, therefore, we have, inthe lake ridges of Upper Canada, New York, and Ohio, evi-dence of the existence of an ice-barrier which continued tofill the valley of the Mohawk, and choke up the outlet throughthe St. Lawrence, long after the glacial front farther to thewest had withdrawn itself to Canada soil. A study of theseridges may yet shed important light upon the length of timeduring which this ice-barrier continued across the valley ofthe Fig. 115—Lake Whittlesey, with correlative ice border. (Map by Leverett.)
Size: 2119px × 1179px
Photo credit: © The Reading Room / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookauthoruphamwarren18501934, bookcentury1900, bookdecade1910
