352 GEOLOGY OF OHIO. 



traced at different elevation?, leaving in places four well-marked terraces 

 respectively (commencing at bottom) of eight, twelve, and eighteen feet 

 in height. 



A section across Wilkins Run, in Mary Ann township, shows water- 

 washed sand hills rising in places to the height of one hundred feet 

 above the bottom of the stream. The wide valley and these elevated 

 water-washed and assorted sand hills indicate the influence of water in 

 quantity vastly in excess of any that could be derived from the local pre- 

 cipitation. They are the result of the torrents which followed the melt- 

 ing and retreat of the glaciers which brought down the Drift from the 

 north. 



The following sections of the material beneath the flood-plains and 

 terraces near Newark, furnished me by W. M. Cunningham, Esq., con- 

 firms the above conclusions in regard to the extent of the erosion of the 

 valleys and the foundation of a temporary laks basin at that point. 



FEET. 



1. Soil, alluvium 1 to 2 



2. Yellow clay, with coarse gravel 1 to 6 



3. Ordiuary sand and gravel, sometimes with quicksand. 



4. Blue clay, sometimes in pockets of 20 to 30 feet 2 to 10 



5. Coarse sand and gravel 2 to 4 



6. Blue clay. 



In sinking a well six miles west of Newark a piece of coniferous (?) 

 wood was obtained at a depth of forty feet, 



GEOLOGICAL STRUCTURE. 



The geology of Licking county is largely a repetition of that of the 

 counties lying immediately north of it, and the space given to the de- 

 scription of the geological structure of those counties renders it unneces- 

 sary to enter here into details which would be mere repetition of what 

 has gone before. 



