MURPHREE'S VALLEY; TOPOGRAPHY. 13 



of the mountain, the debris of the Clinton and Trenton rocks. 

 The other side is mainly the detritus of the Lower Silurian 

 Cherts. 



The Eastern Valley. Broad massive ridges mostly of 

 Lower Silurian Cherts, partly of Cambrian Limestone, sepa- 

 rate the Red Mountain Valley from the next valley on the 

 south east, as far up as they are separated. This dividing 

 ridge is very prominent from Village Springs to the Cham- 

 pion Mines, a distance of fifteenTniles. Farther up the val- 

 ley it becomes more knobby and less prominent, and entirely 

 disappears a little above the south-western line of Etowah 

 county. Above this, for ten rriles or more, both of the sub- 

 valleys south-east of Red Mountain are merged into one. 

 Near the upper end of the valley, however, the division be- 

 tween the two sub-valleys is again established by a ridge of 

 lower Silicious (Fort Payne) Chert, which gradually rises up 

 a little beyond Aurora P. O., and increases in height as it 

 curves round the upper end of the Red Mountain Valley and 

 joins there with the curved end of Red Mountain. 



The sub-valley lying on the south-east side of Murphree's 

 Valley has no distinctive name. It might be called the 

 Limestone valley, or the Cambrian valley, as all the exposures 

 of the Cambrian limestone of this region are in it, and for 

 fifteen miles above Village Springs this valley has been 

 mainly scooped out of, and is floored with that rock ; but 

 neither of these names would properly designate its upper 

 part. It will be properly referred to as the eastern or south- 

 eastern sub-valley. It has generally a good soil, and con- 

 tains many good farms. The south-eastern side of it is gen- 

 erally very broken, with ridges and knobs of Clinton and 

 Sub-Carboniferous strata. These are very irregular in out- 

 line, and as their strata dip at high angles, they are generally 

 steep. 



Straight Mountain. Immediately adjoining these ridges 

 #nd knobs on the south-east side is a high ridge of Car- / 

 boniferous rocks, all nearly to quite vertical, and 300 to 400 



