44 



Indiana Universitij Studies 



cut considerably on the outside where the stream is being- 

 entrenched. The present stream fits snugly against a rock 

 wall of Cypress sandstone. It is likely that the other 

 meanders have been somewhat enlarged also. 



Clifty Creek in its initial post-glacial course was perhaps 

 everywhere working in the unconsolidated material of sec- 

 tion 35, but on cutting down it came to the underlying bed- 

 rock, except here and there. Wherever it has become en- 

 trenched in bed-rock, it is now gorge-like. The wide pre- 

 glacial valley flanked with terraces comes to an abrupt end 

 at a gorge just below the mouth of Little Clifty Creek. The 

 present stream has no valley flat here at all, but flows be- 

 tween rock walls composed of Beech Creek limestone below 

 and Cypress sandstone above. This gorge, which is not a 

 pronounced one, ends rather abruptly, and for a short dis- 

 tance the valley widens out to considerable dimensions. The 

 constriction between the rock walls is repeated where the 

 stream turns north at the beginning of the great meander 

 loop about the middle of section 35. The temporary increase 

 in width just mentioned is due to a small pre-glacial valley 

 which emptied northward into the pre-glacial valley of Clifty 

 Creek. The northward loop, as already described, has a 

 wide valley because here the stream worked in unconsoli- 

 dated outwash material which has filled the pre-glacial val- 

 ley. The stream in this very striking meander loop enters 

 into a rock-walled gorge again just south of the center of 

 section 35. The water here is flowing with considerable 

 velocity over a bed-rock floor. After swinging around this 

 northward loop the stream returns to within 125 yards of 

 itself ; but the short distance between the two limbs of the 

 meander is separated by a high sandstone ridge. In making 

 the broad southward loop the stream encounters a small, 

 fairly broad pre-glacial valley trending northward, and fol- 

 lows the latter to the northward. On rounding this meander 

 the stream hugs a steep cliff of Cypress sandstone. This 

 turn to the northward is due not only to the presence of the 

 pre-glacial valley, but also to the height of the ridge to the 

 west. The initial stream flowed northward until the height of 

 the ridge lessened sufficiently to permit it to cross. It did not 

 come quite far enough at this place to reach the pre-glacial 

 valley of Clifty Creek. Initial flow to the northward was 



