554 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



gentle swells and sags along its crest. There are minor ridges between 

 Zanesville and Ossian on the north side of Eightmile Creek. This creek 

 cuts through the main portion of the moraine at Zanesville, having here a 

 valley fully twice as deep as it has on the plain which it enters west of the 

 moraine. Between Zanesville and Aboit the moraine consists of a single 

 ridge with slopes a mile or more in length. These slopes, as well as the 

 crest, carry swells 10 to 20 feet in height. The ridge is distinctly maintained 

 nearly to the old lake outlet south of Aboit. There the "Huntington wagon 

 road" crosses it in sec. 17, T. 26, R. 11 E.; its altitude by pike survey is 

 about 75 feet above the court-house square at Fort Wayne, and 30 to 40 

 feet above the altitude at the county line, IJ miles west of the crest. It is 

 fully 100 feet above the lake outlet at Aboit. 



The gap in the moraine through which this old outlet passes is 1^ to 1 J 

 miles wide. The marsh which now occupies it is bordered by very abrupt 

 bluffs, 50 to 75 feet in height, composed entirely of glacial drift. Just north 

 of the outlet, near the mouth of Aboit River, several basins occur among 

 the morainic knolls. They deserve especial attention, since such features 

 are rare, saucer-like sags being the usual form, and these are not common. 

 Dryer has published the following brief account of the group of basins 

 referred to:^ 



Upon the bluff near the mouth of the Aboit River (sees. 29 and 32, Aboit 

 Township) there is an interesting group of typical potash kettles, seven within a 

 space of about 30 acres. The largest forms an irregular depression 750 feet long, 

 and from 100 to 200 feet wide. The rest are smaller, of oval or circular outline, and 

 about 20 feet deep. 



The northwest limb of this morainic loop consists, as a rule, of a series 

 of swells and sags, and low, winding ridges which apparently have no 

 uniformity of treiid or system in their arrangement. Along Aboit River 

 for several miles from the mouth of the stream knolls 30 to 40 feet in 

 height are common. There has been nuich erosion along the north side of 

 the lake outlet west of Fort Wayne, which obscures, to some extent, the 

 morainic features, but 2 or 3 miles back from the outlet the morainic 

 topography may be seen to good advantage. Throughout much of the 

 tract in Allen and Dekalb counties the swells fall below 15 feet in height, 

 but in northern Allen County there is a prominent ridge, known as "Dutch 



' Sixteenth Ann. Rept. Geol. Survey Indiana, pp. 121-122. 



