THE CHAMPAIGN MOBAIETC SYSTEM. 229 



They are somewhat elongated in a NW.-SE. direction, and rise abruptly 

 to a height of 20 or 30 feet. Farther east, in the vicinity of Bloomingdale, 

 the knolls are in some cases 30 feet or more in height. In sees. 24 and 19 

 25 and 30, T. 16, Rs. 7 and 8 W., the moraine consists of a ridge 80 rods 

 to a mile or more in width, on whose slopes and crest knolls 10 to 25 feet 

 in height are numerous. Outside the main ridge there is, in sec. 29, a chain 

 of knolls 15 to 20 feet high, rising abruptly above the bordering plane 

 tract. In eastern Parke County the moraine for a distance of about 10 

 miles constitutes the water parting between Little Raccoon and Sugar 

 creeks, and there is scarcely a mile of this portion on which knolls 1 5 to 25 

 feet high do not occur, while in some sections they reach heights of 30 or 40 

 feet These knolls stand upon a basement ridge whose relief, independent 

 of the knolls, is 30 or 40 feet. In this part of the moraine the knolls are 

 arranged in chains trending parallel with the crest. In southwestern Mont- 

 gomery County, on the south side of Sugar Creek, there are numerous 

 sharp knolls in the moraine, but not a distinct ridging or well-defined crest. 

 North of Sugar Creek the moraine assumes a ridged form near the south 

 line of sec, 34, T. 18, R. 6 W., from which point the ridge leads NNE. 

 through Alamo. Its general height is about 30 feet above the plain west 

 of it, and still more above the bluff of Sugar Creek Valley on the east. 

 Near Alamo, in sees. 23 and 26, several basins occur, the deepest of which 

 are 15 or 20 feet below their bordering rims. The basins usually have 

 outlets through narrow breaks in the rim. West of the main belt for 

 several miles the surface is very flat, but east of it there are ridges and 

 knolls extending to the valley of Sugar Creek. The knolls are nearly as 

 prominent as those in the main belt, but are less closely aggregated. They 

 are separated by nearly plane tracts. The northeast fourth of Ripley 

 Township, comprising a tract 3 or 4 miles wide, is sharply undulatory, with 

 many knolls and ridges 20 to 40 feet high. The moraine here is over- 

 ridden by a late Wisconsin moraine. The latter trends NNW.-SSE., 

 intersecting the Champaign moraine at an angle of about 45 degrees. 



The Inner Ridge of the Champaign morainic system is well defined 

 from its point of separation from the Middle Ridge, near Philo, Illinois, 

 eastward to the Fairmount geodetic station. It is about one-half mile in 

 width and 20 feet in height, and presents a gently undulating surface. 

 South and east from the geodetic station there is a series of knolls and 



