224 Geology of the Country between 



harsh sandstone, this supporting a strata of limerock, which is again 

 covered by slate. This last deposit continues as we progress west- 

 ward, until the whole transition series is covered up by the coal 

 measures of the west. I was anxious to ascertain if possible, the 

 place of meeting of the two great formations, the transition and se- 

 condary ; but although this object was kept constantly in view, I was 

 disappointed in determining the precise point, although satisfied my- 

 self, it must occur within a very limited district. Somewhere be- 

 tween Cumberland and Savage mountain, I am convinced a proper 

 search would exhibit the latter, lying unconformably upon the former. 

 It is probable that the coal strata, approach a little nearer Cumber- 

 land than would appear by the section, as coal is said to be procured 

 within a few miles of that place. 



From Savage mountain, (which is colored to indicate the seconda- 

 ry strata,) for the remaining distance, we see no more those diversi- 

 fied slates and sandstones, that exhibit such an interesting appearance, 

 east of this point. The dark blue limestone is no longer seen with 

 its bassetting edges projecting above the soil. The sandstones and 

 shales and limestones of the coal measures, are now alone visible. 

 The most striking change along this part of the route, when compar- 

 ed with the country previously passed, is the great difference in the 

 position of the rocks, the almost horizontal situation of the strata. A 

 little west of Savage mountain, on the top of a low hill, there occurs 

 a slaty limerock, called there " bastard limestone," and said to be un- 

 fit for burning. It agrees in external character with a similar rock 

 found interposed among the coal strata around Pittsburg. West of 

 the bastard limestone, the rocks in sight along the road, are red slate 

 alternating with red and darker colored sandstones, and evidently 

 abounding with coal, as the numerous pits along the road testify. 

 On the top of Laurel Hill, there are immense masses of a coarse 

 white sandstone, apparently in place, and west of this the dark sand- 

 stones and slates and accompanying beds of coal, continue to the Mo- 

 nongahela. I am unable to give the exact order of superposition of 

 these different strata, along the line of the section, and leave it for 

 those who have leisure to make the necessary investigations over so 

 large a surface. Probably this order will be found nearly the same 

 over the whole secondary district, subject perhaps, to comparatively 

 slight variation. While examining the coal deposits around Pittsburg, 

 I had an opportunity of examining minutely the accompanying strata, 

 the nature and individual extent of these, will be more conveniently 



given in another place. From Savage mountain to the Ohio River, 



