iS BULLETIN OF THE LABORATORIES 



river has worked out a deep and rather broad valley in this region but 

 a glance at the map plate III will show that the Little Scioto does not 

 follow entirely the line of the old valley. The Rocky Fork occupies 

 the old valley for a considerable distance, than leaves it to join the main 

 fork and together they gain the old valley again farther to the south. 

 There has been such a vast amount of erosion along the lower portion 

 of the Little Scioto f and considered in connection with other charac- 

 ters) as to make it very probable that some of the work was done by a 

 larger stream than the present river. 



The old valley floor lies about 300 to 350 feet below the hills which 

 border it and in no case were cliffs observed on either side of the valley 

 although often the slopes were quite steep. The similarity in the topo- 

 graphic forms of this valley to those of the Teazes and Flat Woods val- 

 leys and the portions of the Ohio connecting these elements is very 

 marked, while the dissimilarity to the forms below Vanceburg and 

 above Portsmouth and Guyandotte on the Ohio is as striking. 



In the northern portion of the valley the width increases until it is 

 even greater than that of the Scioto below Piketon. The rock floor is 

 here deeply buried beneath a very compact, finely laminated river silt, 

 good sections of which are revealed in many places by recent erosion. 



The descent of the rock floor also continues to the northward. 

 The present drift plain of the valley presents a high terrace like front 

 along the Scioto valley. 



5. SYMMES CREEK AND SALT CREEK. 



Symmes creek rises near the center of Jackson county and flows 

 southward through Gallia and Lawrence counties and joins the Ohio 

 opposite Huntington, West Virginia. This valley was studied at only 

 two points. Reference has already been made to the character of the 

 valley at its junction with the Ohio where the stream runs in a very 

 deep and narrow trough which it has cut out of the carboniferous rocks. 



At the head waters near the city of Jackson the stream is in a 

 broad and open valley which it shares with the head waters of the south 

 fork of Salt creek which latter flows northwestward into the Scioto at 

 the great bend in the so itheast corner of Ross county. The old erosion 

 valley at Jackson is -over a mile wide and is cut some 200 feet into the 

 tal)le lands. The valley floor rises to the southward and the width of 

 the valley decreases somewhat in the few miles that it was examined 

 south of Jackson. To the northward the valley broadens out rapidly 



