1879.] AUO [Stevenson. 



bench for a considerable part of the way below the mouth of the Youghio- 

 gheny river. It is the bench along the river front at Pittsburgh. 



Benches along George's Greek. The third and fifth benches of the Stew- 

 artstown series are persistent along this creek, but constantly rise up-stream 

 so that at the village of Smithfield the fifth is 304 and the third 200 feet 

 above the river at the mouth of the creek. The rise is quite regular and 

 in this distance the lower one has gained five feet ou the upper one. 



The eighth bench is shown on the south side of the creek near the 

 village of Morris Cross-roads, forming the crests of several flat-topped 

 hills on the divide between George's creek and Grassy run, the latter a 

 tributary to Cheat river. Its absolute level is unchanged, being 1195 feet 

 above mean tide. The sixth bench is found near Grassy run, and the 

 second is there at 80 feet above the run, or 125 feet above Cheat river at 

 its mouth. 



Crossing the divide between Grassy run and Rubbler's run, also tribu- 

 tary to Cheat river, several benches were seen, but their relations could 

 not be made out owing to lack of time. On Mitchell's hill, projecting from 

 Chestnut Ridge almost immediately behind the old Springhill furnace, the 

 eighth bench stands out from the mountain for almost 400 yards. This 

 bench is continuous thence southward to the line of West Virginia, where, 

 as the divide between Rubbler's run and Cheat river, it extends for a long 

 distance eastward and westward. Its elevation was determined on this 

 divide and differs from that near Stewartstown by barely five feet. 



Returning to George's creek and taking the road from Smithfield to 

 Uniontown, which follows the west side of the valley, one finds the third, 

 fifth and sixth benches constantly persistent along the side of Brush ridge, 

 which, as already mentioned, is the elevated land marking the course of 

 the Saltsburg anticlinal. East from the road are some minor benches 

 whose relations were not made out. 



Beyond the creek, on the flank of the mountain, fragments of the eighth 

 bench are occasionally shown, and the same bench is reached on the road 

 at the summit of the divide between George's and Redstone creeks at one 

 mile from Uniontown. 



Meanwhile, in ascending the creek, the fifth bench has shown a constant 

 increase in altitude, so that as the divide is approached, that bench takes 

 place of the sixth and finally is merged into the seventh. According to the 

 barometer, the eighth bench is somewhat higher here than at the mouth of 

 Cheat river, being 1206 feet instead of 1195, but the measurement was not 

 verified. No opportunity was afforded for following out the minor benches 

 in this valley, but their steady rise from the river to the village of Smithfield 

 justifies the belief that they rise with the stream until, at last, the "bottom" 

 becomes merged into the highest bench at the head of the stream. 



Benches on Redstone Greek. No little difficulty was experienced in the 

 attempt to trace out the benches along Redstone creek, which enters the 

 Monongahela at Brownsville, 50 miles above Pittsburgh. From the river 

 to Upper Middletown, 3 miles below Uniontown, the creek is hemmed in 



