Page:Popular Science Monthly Volume 38.djvu/764

This page has been proofread, but needs to be validated.

744

THE POPULAR SCIENCE MONTHLY.

of the glaciers that the river began the task of cutting a new channel for itself the one it now occupies; but when the ice reached and crossed the channel and entered Kentucky, this partly

Map showing the Effect of the Glacial Dam at Cincinnati (Claypole). (From Transactions of Edinurgh Geological Society.)

made new way was likewise obstructed. As a result the water rose higher and higher, backing farther and farther up its valley, until its estimated depth varied from three hundred to six hundred feet.

This article is issued from Wikisource. The text is licensed under Creative Commons - Attribution - Sharealike. Additional terms may apply for the media files.