428 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



THE PICKEKINGTON ESKEE. 



Besides the knolls and weak moraines above mentioned, there are two 

 well-defined esker ridges in this inner border district which help to give 

 relief to the nearly monotonous plain. One of these is called the Picker- 

 ington esker, the other the Circleville esker. The position and trend of 

 each is indicated on PL XIII. 



The Pickerington esker derives its name from the village of Picker- 

 ington, in northwestern Fairfield County, which is situated at its northwest 

 end. The length of this ridge is about 5 miles, its southeastern terminus 

 being in the moraine just west of Basil. It consists of a very small ridge, 

 only 6 to 10 feet high and 4 to 8 rods wide, but it has scarcely a break in 

 it and is a conspicuous feature for one so low. It winds considerably, but 

 has a general west-northwest to east-southeast trend. It is utilized for a 

 wagon road throughout nearly its entire length, and is as dry as a gravel 

 pike. In places the bordei'ing tracts are slightly lower than the adjacent 

 plain and are somewhat boggy, but there is not a well-defined esker trough. 

 In these boggy tracts there is an occasional low knoll of gravel. The 

 southeastern end of the esker does not show a well-marked delta ; but there 

 seems to be an equivalent in a greater amount of sand in the moraine than 

 north or south from the esker. The sandy portion of the moraine occupies 

 2 square miles or more, and seems attributable, in part at least, to the escape 

 of water at the margin of the ice sheet at a time when a portion of the 

 escaping water farther back beneath the ice produced the esker. 



At its northwestern end the esker is associated with several drift knolls 

 or short ridges of considerable prominence. The largest one is .just east of 

 Pickerington and stands 30 feet or more above the bordering plain. It is 

 one-fourth mile or more in length and about one-eighth of a mile in width. 

 Its trend, like that of the esker, is west-northwest to east-southeast. It is 

 strewn with bowlders that are slightly embedded in a yellow clay that caps 

 the knoll. / The imcleus of the knoll is probably sand or gravel. Over an 

 area of perhaps a square mile north, west, and south of this knoll there are 

 knolls 20 feet more or less in height, which give the tract a morainic aspect. 

 The bordering country on all sides is a plain. It is probable that their 

 origin is in some way connected Avith that of the esker. 



The esker itself is made up of gravel and sand of various degrees of 



