OUTLINES. 
145 
On Dan River the coal first shows itself on the surface about 3 miles 
east of Germanton, being imperfectly exposed in a ravine. The coal is 
about 3 feet thick. Some 6 or 7 miles further east, at Stokesburg, there 
are outcrops of three seams in succession, the upper about 3 feet thick, 
with a heavy body of bituminous shales ; the other two were not well 
enough exposed for measurement, but they were explored by a very in- 
telligent gentleman who reports one of them as much thicker than the 
top seam. The black shales and slates crop out at various points about 
the town of Madison ; and near Leaksville a slope was driven some 60 
feet on the coal seam which is here 3 feet thick, and with a dip of 34° 
and considerable quantities were mined during the war. It is classed as 
a semi-bituminous or dry coal. The outcrops show that the coal is con- 
tinuous through the whole length of the belt in this State, which is above 
30 miles. 
The thickness of tliE Triassic series Dr. Emmons estimates at about 
3.000 feet on Deep River ; but owfing to the steeper dips of the Dan 
River beds, the thickness of all the strata represented there would be about 
10.000 feet. But their actual vertical depth to the underlying Archaean 
rocks, is probably less than a thousand feet, in either case. What was the 
original thickness of the formation when first elevated, and before the 
■wasting hv denudation began, can only be remotely conjectured ; but it 
must have been very great, as will appear from the following considera- 
tions : 1. The beds on Dan River, measured at right angles to the dip, 
gives a minimum thickness for that side of the formation of near 10,000 
feet : 2. In the section of the Deep River belt, which is exposed in the 
valley of the Yadkin, not only is there a width of G miles with the usual 
dip of 20°, but there is an additional outcrop more than a mile in breadth, 
ten miles south of the principal belt, which preserves the southeasterly 
dip of nearly 20°, and hence the calculation for a minimum thickness at 
this margin must be based on a breadth of 16 miles, which gives a thick- 
ness of more than 25,000 feet : 3. There is no way of accounting for 
the present position of these beds with their opposite and considerable 
dips, but by supposing an uplift of the intervening tract, such and so 
great, that if the movement were now reversed, it would carry this swell 
of nearly 100 miles breadth into a depresssion much below the present 
level of the troughs in which these remnant fringes lie, so that there has 
been an erosion not only of 10 to 20,000 feet of the broken arch of Tri- 
assic beds over this area^but also of a considerable thickness of the un- 
derlying rocks on which they had been deposited : 4. While this erosion 
of the central parts was going forward, the margins must have suffered a 
very great amount of w r aste, so that the beds which remain, are probably 
