258 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



most conspicuous where tributaries enter. In the valleys of these tribu- 

 taries there are clusters of knolls, as indicated above. Just above the bend 

 near Patriot, Ind., along the west bluff of the Ohio, are clusters of knolls 

 which are composed of clay or poorly assorted material similar to that in 

 the level-topped drift tracts. The highest stand about 150 feet above the 

 Ohio, or at about the level of the plane-surfaced valley tUHng. Their 

 form seems to favor the view that they are due to iiTCgularity of drift depo- 

 sition rather than to the erosion of a plane-surfaced drift deposit. Similar 

 knolls are found on the Kentucky side below Rising Sun, Ind., and in 

 places along the border of the Indiana bluff above Rising Sun, They rise 

 about 50 feet above the level of gravel terraces of Wisconsin age, or 150 

 feet above the river. 



Near Bellevue, Ky., the didft is aggregated in knolls up to a height 

 of 250 to 300 feet above the river, but the drift deposits on the elevated 

 uplands between Bellevue and Burlington, Ky., have a plane surface. The 

 drift is decidedly greater in amount on the southern branches of Gunpowder 

 Creek than on the uplands farther north near the bluff of the Ohio. Near 

 Richmond, Ky., it is a conspicuous deposit within a mile of the limits of 

 glaciation on a branch of Grunpowder Creek that discharges northward, 

 but is very meager on Mud Lick Creek drainage, whose discharge is south- 

 ward. The presence of drift in the Mud Lick di-ainage basin shows, how- 

 ever, that the ice sheet extended beyond the Grunpowder-Mud Lick divide. 



Above Cincinnati, for the 50 miles in which the glacial boundary lies 

 near the Ohio River, there are numerous level-topped remnants of a drift 

 filling that stand about 150 to 175 feet above the river. It is probable that 

 much of that portion of the Ohio Valley received a drift filling up to these 

 heights. Just above Higginsport, Ohio, on the east side of the mouth of 

 White Oak Creek, there is a glacial conglomerate extending up to a height of 

 235 feet (aneroid) above the Ohio, forming a narrow bench on the border of 

 the valley. A drift deposit appears on the Kentucky side opposite Higgins- 

 port which also carries conglomerate masses, but its upper part consists of till. 

 It rises only to a height of 175 feet above the river, its altitude being nearly 

 in harmony with the general drift filling below that point. It is near the 

 Higginsport conglomerate that the glacial boundary swings away from the 

 Ohio Valley toward the northeast. 



The writer has not examined the portion of the border lying between 



