530 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



Along the Scioto and Olentangy rivers there are beds of cobble and 

 gravel up to heights of 30 feet or more above the streams, which are 

 apjDarently of glacial age, but as they occur north of this moraine as well 

 as south the writer is inclined to connect them with a later moraine which 

 crosses these streams near Delaware. On Alum Creek and Big Walnut 

 deposits of gravel and cobble occur, but they have a feeble development 

 compared with that along the Scioto and Olentangy. These streams are less 

 favorably situated for carrying the waters from the later moraine, and this 

 ma}' account for the difference in the amount of gravel deposition. The 

 moraine under discussion does not seem, on the whole, to have had so 

 vigorous di-ainage as the next later one. On the interfluvial tracts all along 

 the outer border of this moraine there is a narrow belt of land a mile or so 

 in breadth characterized by very black soil. This seems to be the product 

 of a swampy condition of the surface at some time, presumably at the time 

 the ice sheet was melting. 



INNER BORDER PHENOMENA. 



No features of special importance were noted between this moraine 

 and its neighbor on the north, the whole tract being a till plain with only 

 an occasional low swell 5 to 10 feet in height. 



WINCHELL's INTERPRETATIONS. 



In his discussion of the features of Union County N. H. Winchell 



recognized and called attention to this moraine, but he seems not to have 



noted its continuation in Delaware and Morrow counties. The features 



which are characteristic of the moraines of a continental ice sheet were so 



little known at the time his report was written (1874) that it does not seem 



singular that the moraine was not recognized by him throughout its entire 



length, but, instead, it is remarkable that the significance of certain portions 



of the moraine were so well understood. Concerning this moraine he says:^ 



Between Big Darby and Mill creeks there is a very noticeable thickening of 

 the drift. It rises into long ridges and high knolls which consist of hardpan or 

 glacial drift. Northern bowlders and stones are on the surface and in the soil indis- 

 criminately, though the same is true to some extent throughout the county. This 

 ridge of drift is greatlj^ developed at New Califoniia, where wells are sunk to the 

 depth of 6-4 feet without meeting anything but "blue clay," the water being bitter. 

 West and south of Marysville 2 or 3 miles the surface is high and rolling, with clay 



Hieology of Ohio, Vol. II, 1874, p. 325, 331. 



