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separating from each other the distinct geological formations which 

 there is but little doubt that it includes. 



Through an exclusive attention to the direction of the drainage of 

 the northern and eastern portions of this division of the state, — as, 

 for example, in Montgomery county, — the designation of Alleghany 

 has been very strangely and unphilosophically applied to a compa- 

 ratively elevated portion of the table lands of that county — and 

 guided by the same principle, in tracing a supposed connected chain 

 which forms the water-shed of both the east and west-discharging 

 rivers, the same title has been applied to a portion of the Blue Ridge, 

 constituting the western boundary of Patrick and Grayson counties. 

 Thus we have the same term applied successively to ridges entirely 

 dissimilar in regard to the materials of which they are composed, 

 and the epochs to which they are geologically to be referred; and 

 what is of much more practical importance, mistaken conceptions of 

 the nature and resources of these districts will be almost certainly 

 suggested, on a first view of them, as delineated upon the map, 

 from the prevailing idea, that a continuous mountain chain, thus 

 bearing a common designation along its entire extent, must of 

 course exhibit great similarity in structure and materials throughout 

 all its parts. Nor is this all : by following the fallacious guide of the 

 direction of the drainage, instead of actually tracing continuous 

 ridges, likely to present a general similarity in character throughout, 

 we are in many cases giving an imaginary continuity to elevated 

 portions of land frequently belonging to successive ridges, and thus 

 creating in imagination a connected mountain in a direction or 

 directions in which none such actually exists. Hence, nothing is 

 more common in descriptions than to hear of the Alleghany passing 

 under the Peter's mountain, near the Sweet springs, traversing the 

 various ridges to the east until it arrives at Christiansburg, and 

 thence by many crooked courses, tending towards the Blue Ridge, 

 until reaching that mountain, it suddenly cuts it off, and bends its 

 own course to the south-west. But during all this description, the 

 speaker is seldom aware that he is describing what, to a great ex- 

 tent, has no original in nature, and that what he represents as one 

 mountain, a continuation of the great Alleghany of the upper and 

 middle portions of the state, here striking across the numerous 

 ridges to the east, and making in its way in that direction under and 

 over and through the numerous mountains which seem crowded in 



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