LM ; I-: L I M 1 N A1J V ( 1 1 A PTK K. 3 



stones of the productive Coal Measures rise to varying ele- 

 vations : from Camden to the Mississippi the river rushes 

 over a smooth floor of solid dove-colored Hamilton lime- 

 stone of Devonian age. 



That part of the State between Rock river and the Mis- 

 -i--ippi. except Jo Daviess and a part of Carroll counties, 

 is mostly high, rolling prairie land, dotted with beautiful 

 iiToves of timber, and abounding: in many small stream-. 

 which afford good mill seats and light water poAvers. The 

 soil is dryer than the flat prairies of Central Illinois. The 

 portion above excepted. being within the productive lead 

 basin, is more abrupt and broken. 



The agricultural and horticultural productions, kinds of 

 timber, mineral wealth, superficial extent of geological for- 

 mations, soils and their capabilities and adaptations, and 

 other matters of scientific and economical interest, will be 

 found set out in detail in the county reports following this 

 article, but need not be again repeated in this place. 



The Mississippi river on the west exposes a fine section 

 of its rocks from Dunleith to Rock Island. At the latter 

 place the Hamilton limestones and Coal Measures both 

 outcrop and are the prevailing rocks as far up as Mo- 

 line; from thence to the south line of Carroll county 

 massive walls of Xiagara limestone in places appear like 

 vast mural escarpments, bounding the broad Mississippi 

 bottoms on the east : about Bluffville the Cincinnati shales 

 and clayey limestones are the predominating rocks; at Sa- 

 vanna the same Cincinnati group is capped with more than 

 a hundred feet of coarse, reddish -brown Xiagara limestone; 

 and as we ascend towards the north line of the State, mas- 

 sive, solid Galena outcrops occur, the famous lead producing 

 rocks of the Xorth-west. 



Leaving these rocky formations for the present, it miy 

 be well to discuss some questions connected with the super- 

 ficial deposits covering them. 



