CHAPTER I. 



GEOLOCV OF yoETHWESTKl^X ILLINOIS. 



That part of the State of Illinois embracing the valley 

 of Rock river, and thence north and west of the same, and 

 more minutely described in the following detailed county 

 reports, is. geologically, agriculturally, and in a maimfactur- 

 imr point of view, one of the most interesting portions of 

 our great State. The valley of Rock river, if indeed the 

 high rolling prairie on. either side can be called a valley, in 

 fertility and beauty of prairie land, is perhaps unequalled in 

 the West. The river itself swift flowing, broad, clear as 

 crystal affords one of the most magnificent water powers 

 in the world. At Camdeii. Sterling. Dixon. Grand DeTour, 

 Oregon. Rockford, Rocktou, and Beloit. excellent dams are 

 already built and extensively used for milling and manufac- 

 turing purposes. Others will be built in due course of time. 

 Almost every half dozen miles contains one or more of these 

 heavy water powers. At one end of the stream are the 

 lumber regions of Wisconsin ; at the other, the coal fields 

 of Rock Island. On either side is the rid test agricultural 



.ion in the State. Along the banks and in the bed of 

 the river are many kinds of stone from the best Silurian 

 formations. .V railroad up the valley, joining the coal and 

 lumber, will be built at no distant day. 



In addition to this, the Government survey of Roek 

 river, made under charge of General WILSOX. and submit- 

 ted in the form of a report to the War Department some 

 four years au>. >hows that the improvement of Rock river 

 2 



