24 THE PREGLACIAL DRAINAGE OF OHIO. 



reverse its direction of flow. It therefore becomes a common 

 characteristic of these abandoned valley floors that they are 

 located on present divides and it follows that wherever found, 

 the old streams crossed the present divides at such points. 

 They will therefore be discussed in connection with the divides 

 in which they occur. As already mentioned, these flat low lands 

 associated with the present divides form one of the notable 

 exceptions to the general topographic features. The most 

 striking case of this kind is the divide which separates the waters 

 of Wolf Creek from those of the East Fork of Little Hocking. 

 In this divide there are three well marked cases and several less 

 notable ones. Those at Layman, Barlow and Fleming are the 

 most important. They were the subject of study by Dr. S. P. 

 Hildreth who wrote as follows in his report of 1838 concerning 

 the valley at Barlow. 



"On Mr. Lawton's farm, in Barlow, township, Wash- 

 ington county, in the midst of the marl region, is a locality 

 of fossil fresh-water shells of the genus Unio. They are 

 imbedded in coarse sand or gravel, cemented by ferruginous 

 matter. The spot on which they are found has once evidently 

 been the bed of an ancient lake or pond. It is now a beautiful 

 valley of a mile or more in width by four miles in length, sur- 

 rounded by low hills. On the south side a small branch drains 

 the superfluous water into the Little Hocking. In digging wells 

 for domestic use in this tract, beds of sand, gravel and plastic 

 clay are passed to the depth of thirty feet, containing imbedded 

 branches of trees, leaves and fragments of wood of recent and 

 living species. Similar valleys and levels are found in the 

 uplands of the western part of the county, lying between the 

 headwaters of the creeks, and are a kind of table-land. From the 

 frequency of these flat lands between the headwaters of the Little 

 Hocking and the south branch of Wolf Creek, it is quite pos- 

 sible that at some remote period the waters of Wolf Creek were 

 discharged into the Ohio River instead of the Muskingum. 

 This opinion is strengthened from the fact that the head branches 

 of the South Fork now rise within two miles of the Ohio, and 

 run northerly, parallel with and opposite to the course of the 

 Muskingum for twelve miles, and joins that river twenty miles 



