OUTER MORAINE OF THE MIAMI LOBE. 309 



knolls rising, in some instances, 40 to 50 feet above the surface. Whether 

 they are the product of this lobe or of the Scioto lobe was not determined. 

 Within the city of Springfield morainic features are developed, a well- 

 defined ridge passing the standpipe and thence southwestward through the 

 southeastern part of the city. There is a distinct ridging in a northeast- 

 southwest direction, and along the crests and slopes are knolls 15 to 30 feet 

 in height. The moraine loses much of its -strengtii in the southern part of 

 Springfield Township, though numerous gravel knolls extend toward Selma. 

 From Springfield Township southwestward to the Little Miami River there 

 is a gently undulating till tract, dotted with occasional gravell}^ knolls, but 

 not a well-defined moraine. A conspicuous group of knolls occurs near 

 the county line about 2 miles northwest of Yellow Springs, the most promi- 

 nent knoll (Polhemus Hill) standing nearly 75 feet above the bordering 

 country. This knoll is elliptical, with a northwest-southeast direction, 

 having a length of about one-fourth and a width of one-eighth mile. Other 

 knolls in its vicinity are 15 to 25 feet in height and of sharp contour. Just 

 west of Yellow Springs is an elliptical knoll with north-south trend which 

 rises about 30 feet above the bordering country. It is 40 to 50 rods in 

 length and 20 to 25 rods in width. On the north l)luff of Little Miami 

 River, near the line of Beaver Creek and Xenia townships, there is a prom- 

 inent knoll at least 75 feet in height. Toward the west, between this hill 

 and Beaver Creek Valley, the undulations are sharper than to the north and 

 the topography again appears morainic. Sharp gravelly knolls and ridges 

 15 to 30 feet high are common, and occasionally an esker-like linear gravel 

 ridge is found among the knolls; till swells with gentle slopes also occur. 

 North of Xenia, between Wilberforce and the Little Miami River, there are 

 several other sharp gravelly knolls 20 to 50 feet high. East and south 

 from Xenia for several miles there is only a gently undidating- till tract. 

 West of Xenia, at the west side of a gravel plain known locally as "Cherry 

 Bottoms," several prominent knolls form a group about one-half mile long 

 from north to south and one-fourth mile from east to west. The highest 

 points are 50 to 60 feet above the plain. Knolls are numerous south and 

 west from this group, but they are only 10 to 20 feet high. East, south, 

 and north from Spring Valley the drift on the uplands consists of gravelly 

 or sandy knolls and ridges 20 to 25 feet in height which Avind and interlock 

 in morainic fashion. This seems to be an interlobate tract of the same age 



