Stevenson;] "UU [Aug. 15, 



Though the observations thus available arc very few, yet they suffice to 

 show that the system of benches in this county is the same with that found 

 in Fayette and Washington. 



The eighth bench of the Stewartstown series Is. shown half a mile west 

 from Jacksonville, near the county line on the Pittsburgh and Bedford 

 road, at 1190 feet above tide ; a still higher one at Jacksonville with an 

 elevation of 1230 feet, is evidently the ninth of that series. These benches 

 are well shown both north and 3011th from the pike, forming the crowns of 

 many hills, while the tenth is distinct north from the Pennsylvania Kail- 

 road. Following the pike one finds the twelfth bench at three miles and a 

 half west from Greensburg, with an elevation of 1380 feet, precisely the 

 same as on the National road many miles southwest ; and at two miles 

 west from Greensburg the ninth (?) is shown with an elevation of 1242 

 feet. Benches were seen north from Greensburg at 1185, 1270, and 1300 

 feet on the road to New Salem, evidently representing the eight and tenth 

 with the intermediate bench seen in Fayette county between the ninth and 

 tenth. 



The highest point at the village of New Salem is on the eleventh bench, 

 which is of wide extent in that part of the country. The benches are fine- 

 ly shown west from New Salem along Turtle Creek and its tributaries, but 

 unfortunately, all of the measurements made in that vicinity proved alto- 

 gether worthless, owing to flagrant variations in the barometer. 



Measurements made on the Bedford pike near Latrobe, as it descends to 

 Loyalhanna creek, showed the fifth, sixth, eighth and ninth benches at 

 1050, 1105, 1185 and 1240 feet above tide. The fifth is here the 

 "bottom" of the Loyalhanna. The highest plain seen near the pike is 

 about 1450 feet above tide. 



Benches in the Ligonier Valley. 



On the National Road. There was no means of verifying the measure- 

 ments made here. The base used is the altitude of Chestnut Ridge 

 summit as determined by the original survey at 2400 feet above tide. This 

 determination agrees closely with that shown by the barometer, the rail- 

 road level at Union town being taken as the base ; but as gross errors were 

 made by the engineers in running the line for the road, and as there is no 

 well-fixed point nearer than Uniontown, the altitudes of the benches can- 

 not be regarded as fairly determined. At the same time it may be best to 

 record the levels obtained, because they show that the surface of Ligonier 

 Valley is marked by horizontal benches precisely similar to those seen on 

 the west side of Chestnut Ridge: The following series was made out be- 

 tween the summit and the village of Farmington, midway between Chest- 

 nut and Laurel Ridges : 2155, 2060, 1965, 1880 feel above tide. The crowns 

 of the hills in this part of the valley are almost absolutely level and the es- 

 carpments of the benches arc very steep. The forms stand out more fairly 

 than they do west from Chestnut Ridge. 



South from the National road, Laurel Ridge loses its mountain character 



