256 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



This ridge was brought to notice by E. T. Cox, of the Indiana survey, in 

 his report on Jackson County,^ and its position was indicated on the county 

 map accompanying that report. With the ridge Cox included some sand 

 hills southeast of Seymour, which are evidently of different origin from the 

 ridge. The northern terminus of the ridge is at the south bank of Mud 

 Creek, 3 miles due south of Seymour. From this point it leads slightly 

 west of south through Dudleytown toward Mount Sidney, a distance of 

 about 8 miles, its sovithern terminus being 3 miles north of Mount Sidney. 

 The village of Dudleytown stands about the middle of the ridge. The 

 width nowhere exceeds 1 mile, and is usually scarcely a half mile. The 

 height ranges from 50 to 170 feet above the bordering plain. Being so 

 narrow its highest portions constitute a prominent feature in the landscape, 

 rivaling the hills that have a rock nucleus. That this ridge has not a 

 nucleus of rock is shown by a series of wells whose sections are given 

 below. From these sections it appears that the drift extends in places to a 

 level fully 50 feet below the base of the ridge, and contains till as well as 

 assorted material. The crest of the ridg-e is very uneven, dropping down in 

 places to within 50 feet of the bordering plain, and then rising to 100 feet, 

 and in one place to 170 feet by surveyor's level, above the plain. There is 

 little question that the ridge should be classed as a moraine. It was so con- 

 sidered by Cox at a date when but a few moraines had been recognized 

 in North America. While several moraines of Wisconsin age, in Indiana, 

 exceed it in bulk, none of them forms a more prominent landscape feature. 



From the terminus of Chestnut Ridge southward to the Ohio River the 

 drift on the lowlands is usually a continuous sheet which in places reaches 

 a depth of 40 feet or more, but on the uplands along the extreme border 

 there are in places only scattering bowlders to indicate the glaciation. The 

 surface of the drift on the lowlands is very flat, with scarcely a trace of 

 knolls or ridges. 



Along the Ohio Valley the character of the drift border is extremely 

 variable. In jjlaces only bowlders and thin patches of drift are jDresent, 

 while in other places there are knolls and ridges of considerable size. 

 Among the common features in northern tributaries of the Ohio, a short 

 distance inside the glacial boundary, are clusters of large knolls standing 

 near the base of the bluffs, or plastered on the slopes. Some clusters con- 



' Kept. Geol. Survey Indiana, 1874, pp. 41-75. 



