MAIN MORAINIC SYSTEM OF THE MIAMI LOBE. 363 



Carlisle, where an old valley, probably interglacial, is partially filled by 

 the moraine. Near the railway station in New Carlisle there is a gravel pit 

 in which no till appears. The gravel is in various positions — oblique, 

 arching, and horizontal — and varies greatly in coarseness within short 

 distances. Southeast of the station there is a cutting in which gravel and 

 cobble appear near the top, beneath which is a yellow till 10. or 12 feet in 

 depth, and beneath this blue till. The gravel and cobble increase in thick- 

 ness in passing northwestward, owing to the dropping off" of the till. It 

 seems probable that the till belongs to an earlier ice advance than that 

 which produced the gravelly hillocks that cap it, presumabl}^ the early 

 Wisconsin. West of New Carlisle there are extensive excavations showing 

 a large preponderance of assoi'ted material in oblique and arching as well 

 as horizontal attitudes. In one instance the knoll is capped by till and 

 bowlders, while the nucleus is of assorted material. 



A good exposure of the structure of nearly plane-surfaced upland drift 

 appears at the Beavertown quarries 3 to 4 miles southeast of Dayton. 

 There is being removed here 'about 20 feet of drift, consisting of an almost 

 continuous capping of yellow till 5 to 10 feet in thickness, beneath which 

 are deposits of poorly assorted gravel and sand horizontally bedded. In 

 places these gravelly deposits reach to the limestone, but fully as often a 

 thin bed of till intervenes. The surface of this lower till is uneven, and the 

 gravel rests unconformably upon it. The lower beds of gravel being 

 horizontal, are shut off where the till rises above their level. This break 

 between the lower till and the overlying deposits may indicate a lapse of 

 considerable time between their depositions, though it is not known but that 

 the erosion of the surface of the lower till was rapidly accomplished by 

 the same streams which deposited the overlying gravel and sand. 



A series of interesting sections of plane-surfaced lowland till appear 

 along Twin Creek in the vicinity of Germantown, in a district lying between 

 the outer and middle members of this morainic system. These are of 

 especial interest, since in one locality a peat bed outcrops beneath the till. 

 Attention was first called to the exposures just below (east of) Germantown 

 in 1870, by Orton, who gave at that time an account of the deposits of peat 

 beneath the till.' More recently Wright ^ has called attention to the same 

 deposits and added some interesting observations on the occurrence of 

 sheets of till that perhaps mark successive advances and retreats of the 



1 Am. Jour. Sci. , 2d series, Vol. L, 1870, pp. 54-57. ^ Bull. U. S. Geol. Survey No. 58, 1890, pp. 96-98. 



