SALT CREEK DRAINAGE SYSTEM. 179 



is filled for a great depth with drift. They have also correctly placed the old 

 divide at "the narrows," just above the line of Hocking and Vinton counties. 

 The stream follows the broad valley southeastward past Adelphi and Haynes 

 to the mouth of Queer Creek. It there turns southward into a much nar- 

 " rower valley which soon contracts to a width but little greater than the 

 stream, showing clearly the position of the old divide. After passing the 

 old divide the valley gradually widens as the old southward-flowing drainage 

 is entered. 



An oil boring recently made in the middle of this valley near the 

 mouth of Queer Creek shows the rock floor to be only 35 feet below the 

 present stream. The stream is estimated to be not far from 650 feet above 

 tide at that point, making the rock floor fully 600 feet. This is sufficiently 

 low to fit in well with the altitudes of the valley floors in the midst of the 

 Scioto Basin, which are found to be not far from 550 feet above tide. 



Probably the drainage along the line of the old channel from Adelphi to 

 the Scioto was somewhat different from the present, for the tributary valleys 

 have usually been completely concealed by drift. Laurel Creek, which 

 enters at Adelphi, cuts off a rock point near its mouth. As a result of this 

 filling it enters the stream a short distance east of the old mouth. At this 

 place its valley is narrowed to scarcely one- eighth the width of the old 

 vallej'. 



The portion of the North Fork south of the old divide lies outside 

 the glacial boundary, and it seems to have suffered no change aside from 

 that of the accession above described. 



The Middle Fork of Salt Creek lies outside the glacial boundary and 

 apparently drains all of its old drainage basin. Only the lower course was 

 examined by the writer, and this has a valley but 60 to 100 rods wide, 

 which seems a natural width for a drainage basin of this size. 



The South Fork of Salt Creek has suffered some reduction in the size 

 of its drainage basin. It formerly received the headwater portion of 

 Symmes Creek, as indicated in the discussion of that stream. The jjresent 

 divide at Camba is in a valley which opens northward and carries a silt fill- 

 ing of considerable depth. This silt is calcareous, a feature which indicates 

 that it was derived from the glacial waters, for this is a sandstone region. 

 The valley seems to have been ponded with water to such a height that an 

 outlet was found across a low divide at its lieaxl. The amount of glacial 



