36 GEOLOGICAL SURVEY OF ALABAMA. 



the west and north-west to the Warrior, and the main head 

 of Canoe Creek, which flows east and north-east to the Coosa. 

 In that depressed basin, where streams flow in from every 

 point of the compass, it unites with the Coosa, whose whole 

 course has been in the opposite direction. 



This great swell whose highest points are in this cove re- 

 gion, extends east and south-east to the Coosa river, making 

 a very well marked watershed, and west and north-west as 

 far at least as the Warrior river. But a still more prominent 

 and important swell, with the same south-east and north- 

 west trend and extending more than half the breadth of the 

 state, makes the great watershed between the Tennessee, 

 and the Warrior and Sipsey rivers. From the eastern side 

 of Blount county to near the western boundary of the state, 

 a distance of more than a hundred miles, not a single stream 

 crosses this divide. Even where the great Sequatchie fold 

 was cut through it, near its south-eastern end, it still makes 

 a very distinct watershed. Many other regions of elevation 

 of less prominence, but with the same trend and apparently 

 the result of the same cause, might be given, and many 

 others which show the modifying power of both lateral and 

 transverse pressure. But these are deemed sufficient to fix 

 the reader's attention on this class of phenomena, and im- 

 press the fact that this force has been one of the main fac- 

 tors in complicating the structure, and shaping the topography 

 of this region of country. 



OTHER PECULIARITIES OF STRUCTURE. 



Absence of certain formations on the south-east side of the 

 valley. Before proceeding to details, it may be well to 

 notice some features peculiar to the south-east side and upper 

 end of this valley. One of these is the entire absence of the 

 Trenton limestone on that side of the valley. 



A short distance below Village Springs is the last exposure 

 of these rocks at the foot of East Red Mountain. From that 

 point to the head of the valley, they are not exposed on that 

 side. Opposite Village Springs, the lower Siluran chert and 



