THE ATLANTIC SYSTEM OF MOUNTAINS. 36/ 



Atlantic range, in the hope that the public will see that the name Appalachian ought 

 never to be applied to any of the New Hampshire mountains. 



The Atlantic system of mountains includes the high lands bordering the Atlantic 

 ocean between Newfoundland and Alabama, bounded westerly by a depression readily 

 traceable from the St. Lawrence and Hudson valleys to East Tennessee and northern 

 Alabama. It may naturally be divided into three sections, — northern, middle, and 

 southern, each entirely encircled by low land, if not the level of the sea. 



The northern section is confined to Newfoundland, entirely surrounded by water. 

 The culminating point is about 2,000 feet. The Nova Scotia elevation may be regarded 

 as a branch. 



The middle section, with a Green Mountain branch, is nearly encircled by tide-water, 

 having the St. Lawrence gulf and river opposite a great portion, thence following the 

 Champlain depression to the Hudson, the highest divide being 150 feet above the sea. 

 From Albany to New York, and thence around to the starting-point, it is all tide-water. 

 The culminating point is Mt. Washington, 6,293 feet. 



The southern section is the longest and highest, reaching 6,700 feet in western North 

 Carolina. The eastern boundary is washed by the sea ; and the western is the great 

 valley between the Hudson and Alabama. 



The course of the Great Appalachian valley may be traced minutely thus : From the 

 St. Lawrence to Lake Champlain is a rise of 90 feet. Sixty feet more brings us to the 

 highest point in the depression between Lake Champlain and the Hudson river. The 

 valley leaves the Hudson west of the Highlands, strikes across through northern New 

 Jersey to the Kittatinny in Pennsylvania, 10 to 18 miles wide, and from 200 to 600 

 feet high. There is then a descent to the Potomac, and an elevation to the head of 

 the Shenandoah. Continuing southerly, this valley rises to 2,595 feet at the highest 

 part, near the sources of the Holston river. Following the great valley of Virginia, the 

 altitude is 2,741 feet near the south line of the state, 898 at Knoxville, and 675 feet at 

 Chattanooga. The highest part of this valley in Virginia does not correspond in lati- 

 tude with the culmination of the mountains, as that point is reached in western North 

 Carolina. This valley is regarded as the western boundary of the Atlantic system, and 

 the eastern limit of the Appalachian ranges. 



A section from East Virginia to Cincinnati crosses five different types of orographic 

 structure. First, is the Atlantic plain, nearly 150 miles wide. No mountains exist in 

 it. The elevations are those made by streams cutting into the Cretaceous and Tertiary 

 horizontal deposits, which when protracted display crenulated edges. Second, are the 

 elevations of the Atlantic system known as the Blue Ridge, with obtusely pointed sum- 

 mits. Third, is the valley of the Shenandoah. Fourth, are the long, narrow Appala- 

 chian ridges or the Alleghany Mountains. Fifth, is the elevated plateau, called collec- 

 tively the Cumberland-Alleghany-Catskill plateau, with a quaquaversal arborescent 

 drainage. The Hudson river, with its Mohawk tributary and the Susquehanna river, 

 cut across all these five types of orographic structure. 



Most authors call the Atlantic and Appalachian systems by this latter name only. I 



