334 



EARTH FEATURES AND THEIR MEANING 



for some three hundred miles entirely around the southern and 

 western margins of Lake Erie, this beach is for much of the dis- 

 tance the famous " ridge road " (Fig. 362). 



Lake Warren. As the ice advance which had produced Lake 

 Whittlesey came to an end, the normal recession was resumed 

 and a lake once more formed as a body common to the Saginaw 

 and Erie basins. This lake, known as Lake Warren, extended 

 a shrunk arm far eastward along the ice front into western New 

 York, though it was still blocked from entering the great Mo- 

 hawk valley (Fig. 363). 



Lakes Iroquois and Algonquin. It must be evident that 

 toward the close of the Lake Warren stage a profound change was 



FIG. 364. Map of the Glacial Lake Algonquin (after Leverett). 



imminent a transfer of the glacial waters from their course to 

 the Mississippi and the Gulf to the trench which crosses New 

 York State and enters the Atlantic. So soon as the ice front had 

 retired sufficiently to lay bare the bed of the Mohawk, an outlet 

 was found by this route and its continuation down the Hudson 

 valley to the sea. The Lake Ontario basin now became occupied 

 ,by a considerably larger water body known as Lake Iroquois, and 



