which afford a Passage to Rivers. 39 



gitudinal valleys, as well on the north-west side as on the 

 south-east. M. Brongniart names two on the north-west, 

 and five on the south-east, which are so circumstanced. I shall 

 mention only the three last. 



The Susquehanna, which descends from the very crest of 

 the Alleghany chain, cuts the Blue Mountains at their middle, 

 in Pennsylvania. 



The Potomack, which forms the hoimdary between Mary- 

 land and Virginia, follows precisely the same route ; it inter- 

 sects the same chain as the Susquehanna, and at this place 

 another river joins it, in order to pass together through the 

 same crevice. 



The river James, which traverses Virginia, and likewise 

 descends from the highest ridge of the Alleghanies, intersects 

 the mountains of the north, and those of the south, which are 

 chains of the second and third rank, and likewise two other 

 longitudinal ridges occurring between the latter chain and the 

 sea-coast. 



In the States of Carolina and Tennessee, the river Tennes- 

 see crosses three mountain-chains, that of Coweta, the Wuaka, 

 and the Chilhowe mountain. Other rivers join the Tennessee, 

 namely, the French-broad, and a second, both of which cross 

 the Pecko-Grant's chain, which forms a continuation of the 

 Smoky Mountains. After the junction of all these tributa- 

 ries, the Tennessee traverses three ranges of mountains, named 

 the Lookout Mountains. 



The geological map of Georgia, of North Carolina, and of 

 eastern Tennessee, by .Jacob Peck, shews these passages of the 

 rivers very distinctly ; one would be disposed to say that the 

 mountains had been cut across for the express purpose of af- 

 fording an outlet for their waters. 



The American Jovu-nal of the Arts and Sciences, vol. xix. 

 pp. 6 and 7, contains an account of a voyage along the river 

 Lehigh in Pennsylvania, and of a passage across a defile in a 

 chain of mountains called Blue-ridge, of which the following is 

 an extract : — 



" As we approached the gap, the view became very beauti- 

 ful, and as we entered it by the side of the Lehigh and of the 

 fine canal upon its left bank, the mountain-ridge, here cleft 



