586 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



just north of it a sharp knoll 12 to 15 feet high, were noted. The ridge 

 continues south to Lodi, in Harrisville Township, where it unites with the 

 outer one. The inner ridge crosses the northwest corner of Chatham 

 Township in a northeast-to-southwest course, being combined with the 

 middle ridge in the north part of the township, but entirely distinct from it 

 throughout its course toward the west. 



The inner one of the ridges above noted is developed as a distinct ridge 

 for a distance of 20 miles farther west, and its general course was outlined 

 in connection with the distribution of the moraine. It has a width of only 

 one-fourth to one-half mile, but stands 10 to 25 feet above bordering tracts. 

 Between it and the mam Defiance moraine there is a nearly plane tract 

 rising toward that moraine, whose main crest from Black River westward 

 lies 2 to 5 miles south of this inner ridge. The ridge may be traced without 

 difficulty as far west as the bend of Black River in southwestern Brighton 

 Township. West of this stream there is no well-defined ridge, but drift 

 knolls are quite numerous for a short distance, when the morainic topography 

 disappears, there being a nearly plane tract both to the north and west. 



Returning to the main ridge at Lodi, we find a sharply rolling belt 

 standing 15 to 30 feet above the Harrisville Marsh, which borders it on the 

 south. There are shallow basins both on the crest and slopes. Some of 

 them contain boggy bottoms but none were observed to hold lakelets. The 

 moraine crosses a western tributary of East Black River, 2 miles southwest 

 of Lodi. It then curves to a course north of west and follows the north side 

 of that stream to its source, there reaching a culminating point with an 

 altitude about 1,180 feet above tide, from which it descends southward to 

 the Vermilion River. It consists throughout this portion of its course of a 

 single ridge with sharp crest, on the slopes of which there are numerous 

 gentle swells 5 to 15 feet in height. It is more conspicuous by its relief than 

 by its knolls or morainic contours, the relief being 20 to 40 feet and rather 

 abrupt. The inner slope has but gentle undtilations as far west as the 

 meridian of New London, beyond which it is dotted with sharper drift 

 knolls, which become more and more numerous upon approaching Vermilion 

 River, until at the east bluff' of the river they constitute a very sharply 

 morainic belt which extends north a few miles as a spur from the moraine. 

 The northern end of the spur is about a mile north of the corners of Hartland, 

 Clarksfield. New London, and Fitchville townships, Huron County, where 



