434 GLACIAL FORMATIONS OF ERIE AND OHIO BASINS. 



miles south of the statehouse, an artesian well passed through 106 feet of 

 drift, of which the upper 50 feet is gravel and the remainder sand. Water 

 comes from below shale at a depth of 148 feet. The water rises 3 or 4 feet 

 above the level of the canal at Columbus. 



At the starch factory in the south part of Columbus, near the canal 

 and river, several flowing' wells have been obtained from the drift at depths 

 ranging from 40 to 90 feet. They are said to pass through "hardpan" just 

 above the water vein. Whether this hardpan is till or cemented gravel was 

 not learned. The main part of the drift penetrated was graA'^el. 



At the Lutheran College, in the east part of Columbus near Alum 

 Creek, a well 110 feet deep did not reach hard rock, but maj- have entered 

 shale. At the waterworks on Alum Creek several flowing wells were 

 obtained at depths of 30 to 40 feet. They penetrated about 12 feet of 

 gravel at the surface and were then in till to the water vein. This water 

 is strongly chalybeate. The bluffs on Alum Creek on each side of the 

 waterworks are composed of till; the gravel is therefore strictly a valley 

 deposit. Orton has made the following statements concerning the erosion 

 near Columbus:^ 



The erosion has been especially extensive near the junction of the two rivers. 

 For 3 miles at least above the mouth of the Olentangy the rocks between the rivers 

 have been cut away to such a depth that no trace of them is now visible even in the 

 deepest wells that are dug. The drift deposits that take their place do not rise to the 

 same altitude that the surrounding uplands attain, and thus the whole of the country, 

 from North Columbus westward to the Scioto, belongs in the categor}' of lowlands. 



Immediately north of this lowland tract the altitude is not only greater, 

 but the drift much thinner, so that the erosion was far greater than is 

 indicated by variations in the level of the present surface. 



On the plain southwest from Columbus the drift is 10 to 50 feet or 

 more in thickness. On Darby Creek there are occasional outcrops of rock 

 in Franklin County as far south as Harrisonville, but from that village to its 

 mouth no outcrops were observed, though the valley is in places 75 feet in 

 depth. In the portion of Deer Creek immediately west from the lower 

 portion of Darby Creek, rock outcrops are numerous. The heavy drift 

 does not, therefore, extend much farther west than Darby Creek. It may 

 occupy the entire interval between that creek and the Scioto in Pickaway 

 County. 



•Geolojfy of Ohio, Vol. Ill, 1878, p. 599. 



