CAHABA COAL FIELD : HENRYELLEN BASIN. 37 
The surface area of the basin is one hundred and nine- 
teen square miles. The most valuable portion of the basin 
is on the southeast side ; a large amount of the north west- 
ern portion, occupied by Shades’ Mountain, or Rocky 
Ridge, and Black Jack Ridge, contains no. seam but the 
Brock and another thin seam, and as yet I-have never seen 
them of workable size in the Cahaba Coal Field, though 
the same seams in the northern portion of the Warrior 
Field and in Tennessee hold four feet and over of good 
coal. 
For a fuller description of the rocks of the Henryellen 
basin, see vertical section on accompanying map, also Chap- 
ter I, giving a general description of all the prominent 
ledges in the Cahaba Coal Field. For description of the 
territory surrounding the Henryellen basin see introductory 
chapter. 
The measures of this basin have a varying rate of dip. 
That portion of it occupied by the Millstone Grit shows a 
rate of dip generally of from nine to twelve degrees; the 
measures in sections 6,7, 8 and 18, in township 16, range 
2 east, are nearly flat or level; also in sections 13 and 24, 
township 16, range 1 east, they are nearly flat; the strata of 
other parts of the basin have mostly a rate of dip varying 
from five degrees to twenty-seven without taking into ac- 
count the fault vertical coal measures of the southeast 
boundary. 
The Coal Measures of the Henryellen basin have a thick- 
ness of five thousand feet. In the southern portion of the 
basin the thickness is a little over that amount, or nearly 
one mile, counting from the base of the Millstone Grit up 
to the top of the highest strata of the Coal Measures in the 
basin. 
The following analysis of coke made from the coal of the 
Mammoth seam at DeBardeleben Coal & Iron Company’s 
Mines, at Henryellen, was made by Alfred Ff. Brainerd, 
chemist, Birmingham : 
