328 GEOLOGY OF OHIO. 



A section across the stream from Mt. Vernon west, gives a much broad- 

 er alluvial plain, a similar succession of terraces rising gradually to land 

 covered with unmodified clay Drift, containing striated boulders. 



The hills east of Mt. Vernon are generally covered with Drift contain- 

 ing abundant debris of Waverly, and many granitic boulders. Patches 

 of typical clay Drift are most abundant on the slopes near the top of the 

 hills, and in places exposed ten feet thick. 



Following the Columbus road westward toward Mt. Liberty, the sur- 

 face rises very slowly from the river over a bed of fine gravelly and sandy 

 alluvium, filled with small bowlders, many of them of limestone, then 

 striking irregular drift-hills which reach an elevation one hundred and 

 fifty-five feet above the railroad at Mt. Vernon. The material of these 

 hills is coarse, consisting chiefly of gravel and sand, with flat fragments 

 from the Waverly, and a few large granitic bowlders. The surface is 

 irregular and billowy, as if piled up by the action of shore waves when 

 the water stood at this elevation. Thence to Mt. Liberty the surface 

 rises to the height of two hundred and twenty-five feet above the rail- 

 road, the wagon road passing over undulating Drift hills, the materials 

 steadily becoming coarser, containing more limpstone, and more flat 

 fragments of rock. The underlying strata are entirely covered by this 

 deposit. Wells on the hills at Mt. Liberty show, 



FEET. 



1. Gravel 15 



2. Blue clay 5 to 15 



when quicksand, resting upon shelly siindstone, is reached, and affords 

 an abundant supply of water. 



West of Mt. Liberty a cut on the railroad at an elevation of two hun- 

 dred and eighty-five feet above the depot at Mt. Vernon shows that the 

 Drift is wholly unstratified. It contains a large percentage of small 

 limestone bowlders. Many of these are striated, but none of them rolled 

 or water- worn. Finely broken, irregular fragments are abundant, and a 

 moderate quantity of flat and broken pigments of the Waverly are seen. 

 This is typical unmodified glacial Drift, and this deep gorge was filled 

 with it to the height of at least two hundred and eighty-five feet above 

 the present bed of the stream. Similar deposits yet remaining in pro- 

 tected places on the level of the stream show what was the original 

 material which filled the valley. 



In miliar township the hills are composed of tenacious clay Drift, the 

 wells showing eight to eighteen feet of yellow clay, then blue clay pass- 

 ing into hard-pan on the hills and resting on quicksand in the valleys. 

 On the bottom lands of the stream we find — 



