to 



an area, which, for the present, does not admit of being accurately 

 defined. Limestone strata of vast extent, hydraulic lime, marble, 

 travertine or deposite marl, slate, iron ore, and in the south, lead ore, 

 are among the valuable materials included in this section of the 

 state. Declining to apply the title of Transition to the strata of 

 which this region is composed, because much additional observation 

 is required for the determination of their true geological relations, 

 we must for the present be content with referring them to the oldest 

 of that group of rocks in which the organic remains or fossils have 

 been discovered. 



(4.) — The fourth general division to which we shall refer is, at 

 present, even less susceptible than the preceding, of being defined by 

 lines of precise limitation. Nearly the whole of its surface is occu- 

 pied by chains of mountains, and extremely little has hitherto been 

 done towards exploring its geology. In general, it may be described 

 as comprised between the western limits of the great valley forma- 

 tion and the front ridge of the Alleghany, the Greenbrier and Muddy 

 creek mountains ; but with regard to its extent and boundaries fur- 

 ther south, nothing definite can be affirmed until it shall have been 

 carefully and systematically explored. Besides the interest in a 

 scientific point of view which attaches to this region, on account of 

 the peculiar structure of its mountains, the stupendous natural sec- 

 tions which it exposes, and the astonishing abundance and variety 

 of the fossil impressions found among its rocks, it claims a high 

 importance from the great value of its materials, economically consi- 

 dered. Its anthracite, pseudo-anthracite, or semi-bituminous and 

 bituminous coals, its limestones, sandstones and grits, and iron ores, 

 and its numerous thermal, chalybeate and sulphuretted springs, con- 

 stitute collectively an amount of mineral treasures of which few 

 other territories of the same extent are as largely possessed. With- 

 out, at present, venturing to apply any precise geological designa- 

 tion to this singularly interesting region, it will be shown to have 

 marked peculiarities which distinguish it from the division pre- 

 viously described. 



(5.) — Our fifth and last division, stretching from the eastern limits 

 of the former to the western and south-western boundaries of the 

 state, presents an area of vast extent, and embraces regions abound- 

 ing in materials of the highest economical utility. 



This immense territory, characterised by nearly horizontal strata, 

 gently dipping towards the west refers itself unequivocally to the 



