82 



PROCEEDIKGS OF THE CANADIAN INSTITL'TE. 



Elevations of various points upon Cumberland tableland above sea 

 level at Mobile Bav. 



Locality. 



Elevation. 



Authority. 



Ctunberland Gap 



1636 



J. G. XeMlee, R. R. Survey. 



Pinnacle near " 



26S0 

 •2200 



.( << 



Pine Mountain 



J. M. Safford, Geol.Tenn.'69, p. 73 



Ben Lomond 









1910 



A. M. Lea, R. R. Survey. 



Racoon Mountains at Whiteside. 



1900 



J. M. SafiFord, Supra. 



Lookout Mountain . . 







2154 



J. M. SafiFord, Geol. Tenn. 09. p. 



Bon Air 







2029 



A. M. Lea, R. R. Survey. 



Tracy City 







1S47 



Sewanee Mining Co. K. R. 



Highest Ridge near Tracy City. 



2161 



" 



Average of 18 points 



onR, 



R.. 



lS-16 



" 



Avei"age Height. 



2036 



Cumberland Tableland. 











Crab Orchard Mountain has an elevation of nearly 3,000 feet, or 

 about 1,000 feet above the general level of the table land. 



The two formations — the black shale and the overlying Protean 

 beds of the sub-carboniferous — extend from the Cumberland tableland 

 on the east ; west, through Tennessee ; north, through the southern 

 and central portions of Kentucky, dividing the coal fields of that 

 State into two divisions, and these beds also extend southward into 

 Alabama. The dip of the underlying Nashville and Trenton beds 

 does not conform to that of the overlying black shale. 



Geological History. 



From the data we have, the geological history of the district ap- 

 pears to have been thus : — 



During the period in which the Lower Silurian formations were 

 being laid down this part of the continent appeai-s to have formed a 

 di\-ision of the gi-eat inland sea, or rather branch of the Atlantic Ocean,. 



