CHAPTER LVI. 



KEPORT ON THE GEOLOGY OF TUSCARAWAS COUNTY. 



BY J. 8. NKWBBRRY. 



SURFACE FEATURES AND DEPOSITS. 



The topography of Tuscarawas coanty has been produced almost ex- 

 clusively by erosion. From the study of its geology we learn that the 

 surface originally formed a plain on the southern slope of the water-shed, 

 having a gentle inclination toward the south. la the lapse of ages this 

 plain has been deeply furrowed by the great line of drainage which trav- 

 ersed it, now known as the Tuscarawas River. The valley of this stream 

 was originally cut to the depth of more than seven hundred feet below 

 the highest lands of the county, and, though now partially filled, it still 

 exists as a broad and deep trough more than three hundred feet below 

 the adjacent highlands. This passes, by a somewhat circuitous route, 

 from the middle portion of the northern border through its central part, 

 making its exit near the south-western corner of the county. The trib- 

 utaries of the Tuscarawas are quite numerous, and some of them are 

 of considerable size, such as Sugar Creek, the Conotton, and the Still- 

 water, and all these having deeply excavated their channels, have formed 

 a network of valleys which give great diversity to most of the surface. 

 The relief, or relative elevation of some portions of the county, produced 

 by the excavations of the valleys, may be plainly seen by any one who, 

 starting from New Philadelphia, will pass to a distance of ten miles 

 either east or west. The town of New Philadelphia is located on a ter- 

 race which reaches northward to Dover, and has an elevation of from 

 forty to fifty feet above the bed of the Tuscarawas. This plateau is the 

 old flood-plain of the river, formed when it ran at a higher level than now. 

 It is composed of gravel, as we know by borings, and is the surface of 

 the mass of Drift that occupies the bottom of the old excavated val- 

 ley. At Dover the borings made for salt have shown that the rock 

 bottom of the valley lies one hundred and seventy-five feet below 

 the present surface of the Tuscarawas. Hence, we learn that the plains 



