Drainage Features of the Upper Ohio Basin. 265 



mouth of the Beaver, or on the supposed outlet along the 

 Beaver and lower Shenango. It is further supported by 

 peculiarities in the drainage of the upper Ohio. Nearly all 

 the tributaries entering the valley above New Martinsville, 

 West Virginia, point northward, i. e. up stream, as the river now 

 flows, while those below point down stream. The suggestion 

 of an old water parting here occurred to the senior writer in 

 a trip up the Ohio some years ago, and we learn that the same 

 thought has occurred to Mr. Carll. 



The junior writer gave some attention the past season to 

 the high-level terraces between Wheeling, West Virginia, and 

 the mouth of the Beaver. Many remnants of these terraces 

 occur in recesses of the valley and on the lower courses of 

 tributaries. 



At first inspection the shelves do not seem to fall into ob- 

 vious systems, and as our work on them is not yet complete 

 we shall express no final judgment here. A preliminary study 

 of the data, however, seems to throw the higher shelves into a 

 very interesting and significant two-fold system. 



Starting with the well developed high terraces at the mouth 

 of the Beaver where the rock shelf is about 880 feet A. T. 

 and the gravel terrace 935 feet, we find, six miles below, a rock 

 shelf at 940 feet A. T. covered with early glacial gravel ; 

 another 12 miles farther down at East Liverpool, Ohio, at 950 

 feet ; another at Wellsville, Ohio at about the same height ; 

 another shelf six miles below Wellsville at Tomlinson Run, 

 at about 1000 feet (without glacial gravel) ; another north of 

 New Cumberland, West Virginia (two miles farther), at about 

 985 feet covered with scattering pebbles, but no Canadian 

 pebbles found ; another at Toronto, Ohio (four miles farther 

 south), has about 10 feet of glacial gravel on a shelf 950 feet 

 A. T. plainly occupying the deepened portion of an old river 

 bend. This is the farthest point to which the high level gla- 

 cial gravels were traced. Although slightly higher than at 

 the mouth of the Beaver they are 15 feet lower at Toronto 

 than at Pittsburg, a feature which indicates that they have 

 suffered reduction at Beaver. About five miles below Toronto, 

 at Holliday Cove, West Virginia, there is an interesting branch 

 of the deeper channel cutting oif an island upland, as it were, 

 which is filled with late glacial gravels. Across this island 

 there passes an old channel of Harmon's creek (an eastern 

 tributary), which stands at 350 feet above the river, or 990 

 feet A. T. Opposite Steubenville, Ohio (three miles below), a 

 shelf stands at about 1000 feet ; another on a western tributary 

 at Mingo Junction, Ohio (two miles farther), at about the same 

 height; another at Wellsburg, West Virginia (four miles be- 

 low), is slightly higher (1005 feet A. T.). This is well devel- 



