F. H. Bradley—silurian age of the Southern Appalachians. 379 
quarried and burned into lime. The position of this outcrop 
indicates that the bed probably has a southeasterly dip, passes 
very near Clarksville (possibly along the depression of the val- 
ley of Soquee Creek), aud is continuous with the outcrop at 
Limestone Spring, about two miles east of Gainesville. This 
ed must also occur on the north side of the anticlinal, along 
the foot of the mountain, but is not yet reported. In passing 
east, as it was not seen on the Clarksville road. Near this 
river crossing, at the Glade Mines, a prominent bed of itacol- 
umyte is reported; and several diamonds have been found in 
the gold washings. The marble, near the Limestone Spring, is 
essentially the same as that of the Valley River belt, but con- 
tains, perhaps, rather more impurities, heavy layers being here 
solid masses of tremolite. So far as seen, the immediately 
orth. The Blue Ridge, which is a single range in northern 
Virginia, forks a few miles southwest of Lynchburg; and th 
two ranges thus formed gradually separate, to the southwest- 
ward, until, in middle and southern North Carolina, they are 
from sixty to seventy miles apart. e main strikes are 8. 
45°65 W.: and, i e eastern range, which is the main 
watershed, these continue through Georgia into Alabama; 
ut the western range, almost from the very point where it en- | 
ters Georgia, bears more to the southward, the strikes being 
mostly about 8. 5°-15° W., and rapidly approaches the eastern. 
This western range, as such, terminates before reaching the 
Etowah River; but the disturbances consequent upon the 
crowding of folds have been felt far to the southward and 
eastward, as we have seen. 
After crossing the Shallow Ford of the Chattahoochee, we 
find more nearly the normal dips of this side of the anticlinal, 
in a heavy outcrop of thin-bedded gneisses, which dip 30°, N. 
62° W., and in the overlying auriferous hydromica schists, 
Am. Jour. Scr.—Tutrp — Vou. IX, No. 53.—May, 1875. 
