261 



high, and they are so short in their duration that the fringing dune 

 has practically always been able to protect the land behind it. Once 

 the average lake level is such that the water is at the foot of the ridges 

 and prairies, as at Kenosha, no vegetation can prevent the steady cut- 

 ting which gradually eats away the ridges, prairies, and marshes. 

 Piers are built to combat this erosive action, but as a rule they merely 

 retard it and do not stop it. 



Genkrai, Description oe the Region 



The region lying between the Glenwood ridge on the west, Lake 

 Michigan on the east, Kenosha on the north, and Waukegan on the 

 south is very shallowly crescent-shaped. Its northern and southern 

 boundaries are marked by the extensions of the Glenwood ridge into 

 the lake as cusps. The length of the area is about 25 kilometers with 

 a width of from 0.4 to 1.6 kilometers. The elevation above Lake 

 Michigan level varies from 0.8 to 9.0 meters. The soil is sandy 

 throughout. 



As seen from the Chicago and North Western railway, which 

 skirts the western edge, the different parts of the region give the fol- 

 lowing general impressions : From Waukegan to a kilometer north 

 of the Lake County pest-house the land is characterized by marshy 

 swales separated from one another by very low sandy ridges. In 

 no place are these ridges two meters above the level of Lake Michi- 

 gan. The vegetation is essentially prairie-like. It is very monotonous 

 in appearance, except during July, when the lilies are in bloom, 

 and during September, when it is covered with blazing stars. The 

 swales are uniformly occupied with swamp grasses and sedges, all 

 of which appear very much alike from the train. There are, at very 

 long intervals, scraggy trees which hardly break the monotony. 



North of this area is another which, though of the same physio- 

 graphic character, gives an entirely different impression because of 

 the groves of pines that occupy the ridges. In consequence this por- 

 tion is termed the area of the pines. It is bounded on the west and 

 north by arms of the Dead Lake. Formerly the extent of this area 

 was much greater both north, south, and west; but upon those sides 

 it is being reduced by cutting, burning, and by natural successions, 

 Avhile the fringing dune and the lake form its eastern boundary. 



From the Dead Lake north to Kenosha is the area of greatest 

 extent. It is wooded, but in this case the trees are oak instead of 

 pine. There are many blowouts, those towards the north being 

 larger and slightly more numerous than those in the southern part. 

 The interridgial depressions, which are not so low as those towards 



