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of the area. TIu- miniiiiuiu annual rainfall of tlie region is about thirty 

 inches, and the run-off may, in dry years, fall as low as twenty-five per 

 cent, of tile rainfall. In the eastern re.uion (Knohslone formation) \vater 

 for muiiieiiial suijply will liave to be impounded, except wliere the under- 

 How of tlie larger valleys may l)e used; and the conditions for building 

 dams are ideal. In the central iiortion of the area the roclc sub.stratum is 

 everywhere very cavernous and leaky, and liirlit ponds will be dithcnlt t) 

 obtain. A few of the larirer springs furnish sufficient water for small 

 cities without imi)oundinf:. All deep wells produce nuneral water, and 

 shallow wells are inadequate. In the western portion the conditions ar.> 

 intermediate between those of the eastern and central portions. To main- 

 tain the perennial tiow of sprin.ij;s and prevent the silting of ponds the 

 steep slopes of the area should be reforested, where necessary, and for- 

 ever kept in forest. 

 Gcolofjical Luhoratory, 

 Indiana Universitu. 



