CHAPTER VL. 
THE EUREKA BASIN. 
The Eureka basin lies southwest of the town of Helena, 
the north end of it being about half a mile southwest of the 
Helena depot, on the South and North Alabama Railroad. 
It is bounded on the north by the Helena basin, on the 
southeast by the great boundary fault separating the Car- 
boniferous from the Cambrian measures, on the south by 
the Beaverdam fault, separating it from the Dry Creek 
basin, and on the northwest side by the interior fault vertical 
measures. 
The following isa description of its boundary: Com- 
mencing at the great boundary fault on the east side of the 
coal field at a point about half a mile southwest of the 
South and North depot at Helena, thence south by a few 
degrees west, along the boundary fault leaving Hillsboro 
fifty yards to your right, leaving R. T. Dunnan’s house 
about a quarter of a mile to your left, continuing along 
boundary fault until you get nearly opposite Mrs. Peel’s 
house, thence westerly along the Beaver Dam fault, mostly 
along Beaver Dam Creek, to the half mile post of the south 
side of section 25, township 20, range 4, west; this brings 
you to the southeast boundary of the Interior fault meas- 
ures; thence northeast along the southeast edge of the In- 
terior fault, leaving Lainey Ford six or seven hundred yards 
to your left, continuing on northeast until you arrive oppo- 
site the half-mile post on the east side of section 17, town- 
ship 20, range 3, west; thence southeast to the point of 
commencement. Your last course will be nearly parallel 
with the public road, the road being south or southwest 
of it. 
This basin is drained by the Cahaba River and Beaver 
Dam Creek and their branches. 
The most prominent ridge in this basin is the one that 
