THE ADIRONDACK MOUNTAINS 



59 



Fig. II Maps showing three stages in the recession of the 

 great ice sheet from New York State. Upper figure : the 

 Adirondack mountains completely buried under the ice; middle 

 figure: the Adirondacks largely freed from the ice; lower fig- 

 ure : the Adirondacks wholly freed from the ice. Note the 

 position of the large lake in the Black River valley; standing 

 water in the Hudsorl valley and in the Lake George depression ; 

 and the outlet of the Great Lakes through the Mohawk valley. 

 (After H. L. Fairchild, from Tarr and Martin's "College 

 Physiography," by permission of The Macmillan Company). 



