306 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



nearly the whole tract between the two Whitewater rivers. From Conners- 

 ville northward it is closel}^ associated with the outer moraine of the East 

 White River lobe, and the combined moraines occupy -the western half of 

 Wayne County. In northern Wayne County these moraines are overridden 

 by a later one and their noi'thward continuation is completely concealed. 

 It is scarcely probable, however, that they extended farther north than 

 the summit of the highland tract in Wayne and Randolph counties, for it 

 seems natural that the Miami and East White River lobes would have 

 completely -coalesced in the low country to the north of these highlands. 



Wayne County presents features to which it is necessary to direct 

 especial attention, otherwise there may be a misunderstanding of the inter- 

 pretation concerning the course of the moraine. The western part of the 

 county is traversed by a series of large ridges and broad valleys, trending 

 north-northeast to south-southwest, the height of the ridges being 75 to 125 

 feet and their breadth several miles, while the valleys present a usual 

 breadth of about one mile. The drift, as a rule, has considerable deptli, 

 both on the ridges and in the valleys. On the ridges or uplands the wells 

 indicate that the rock surface is generally as low as in the vallej^s, and so 

 far as collected, the evidence all favors the view that the relief of the ridges 

 is due rather to drift accumulation than to rock substrata. 



But it is scarcely probable that it was the last ice invasion which deter- 

 mined the main outlines. The course of the moraine under discussion is 

 such as to carry it into the valleys as well as over the ridges of the western 

 part of Wayne County, yet it scarcely touches either a large ridge in the 

 east-central part that lies between East Fork and Nolands Fork, or the 

 uplands west of the West Fork of Whitewater River. There seems little 

 doubt, therefore, that these reliefs are referable to pre-Wisconsin agencies. 

 This determination raises the double question, whether the earlier ice 

 invasion produced the succession of ridges and valleys here displayed or 

 whether it produced a plane-surfaced deposit which was carved into ridges 

 and valleys b}^ the streams which drained this district in the Sangamon or 

 the Peorian or both of these interglacial stages preceding the Wisconsin 

 glaciation. The contours of these ridges and valleys apparentlj^ support 

 the view that the drift surface as left by the ice was nearl}^ plane, and that 

 a large amount of sculpturing was accomplished in the interglacial stages 

 just mentioned. 



