134 GEOLQGT OF. OHIO. 



shore and shoals which formed the margin ctf the great inland sea that 

 once filled all the basin of the lakes. 



In the northern part of the county the Drift deposits are generally 

 of so great thickness as to cover and conceal the underlying rocks. 

 Wherever exposed to view, the rock surface is found to be planed and 

 grooved by glacial action, and usually the overlying clay may be desig- 

 nated as a bowlder day, since it contains masses of rock derived from 

 neighboring sources, with smaller and usually scratched and worn frag- 

 ments brought from distant localities. This clay is unquestionably the 

 material ground up by the great glacier which once covered Northern 

 Ohio, pushed forward by its advance, and left in an irregular sheet upon 

 the rocky foundation in its retreat. In some places the clay is finer, 

 ■without gravel or bowlders, and is accurately stratified by the action of 

 water. 



Immediately beneath the soil, or projecting above the surface, are 

 found many tran=iported bowlders, frequently of large size, composed of 

 granite, greenstone, and other crystalline rocks, evidently of foreign ori- 

 gin, and apparently derived from the highlands north of the great lakes. 

 These bowlders are rarely found deeply buried in the Drift, and, as I have 

 elsewhere shown, must have been floated by icebergs from their place of 

 origin, and dropped into their present position. Some of the superficial 

 gravels which overlie the bowlder clay seem to have been transported by 

 the same agency. 



As a whole, the soil of Portage county is productive, and although, from 

 its tenacious character, and the dense growth of forest by which it was 

 covered, it has required much patience and labor for its subjugation, this 

 task has been well and thoroughly performed by the intelligent anM in- 

 dustrious population into whose possession it came ; and it has repaid 

 their efibrts by a constant and generous support through the last half 

 century. 



In common with the other portions of the great divide on which Por- 

 tage county is located, its rolling surface forms numerous local basins, 

 many of which have been, and some still are, occupied by lakes. Of 

 these lakes, West Pond, Brady's Lake, and Lake Pepin in Franklin, 

 Mud Lake, Sandy Lake, and Muzzy's Lake in Rootstown, and Fritch's 

 Pond in Suffield, may be cited as examples. These lakes are supplied by 

 springs which flow through the Drift gravels, and their water is usuallj"- 

 clear and pure ; they contain great numbers of fine fish, and are also in- 

 teresting and beautiful features in the scenery. Some of these basins, 

 formerly occupied by water, have been gradually filled up by the growth 



