J. L. Campbell— Geology of Virginia. 198 
logical student will find a problem to solve of no little com- 
plexity, arising in part from the windings of the river, and in 
still greater part from the rupturing and faulting of the moun- 
tains themselves. After passing the ends of both Hog-back 
and Wolf ridges (see section) at the distance of about a mile 
and a half above Wilson’s Spring, he will find the course of the 
river nearly coincident with the strike of the Medina sandstones 
that here dip so steeply on the N.W. face of Wolf Ridge as to 
“pass the lower beds beneath the stream, while those higher up 
are cut through in the direction of their strike. Within view 
of this point, and on the opposite side of the river, a great down- 
fall from the next ridge (N. Mt.) has occurred, around which the 
stream makes a loop of half-a-mile in extent; thisslip, however, 
is quite limited; for above, and on the right and left of the 
fallen mass the Medina sandstones again crop out along the 
face of the North mountain ridges with a moderate northwest- 
erly dip, displaying their full thickness of about 500 feet along 
the southeast face, and, with one slight undulation, and subse- 
quently increased dip passing beneath the Little Goshen valley 
yond, 
After careful and repeated examinations of this portion of 
the “Pass,” Dr. Ruffner and myself agreed that the phenomena 
presented could be accounted for only upon the hypothesis of 
a fault running parallel with the axis of the mountain chain. 
Repeated observations since our original survey have tended to 
contirm the conclusions originally formed. : 
In following the course of the loop in the river, mentioned 
above, we travel a short distance with the strike of the rocks 
toward the southeast, then turn and cross the fault (filled up 
with the débris from the face of the broken mountain), and 
finally change our course to the northeast again following the 
line of strike in nearly an opposite direction, and passing be- 
neath the outcropping sandstones that rise far above our heads. 
But we soon deviate from this course to one at right angles to 
the mountain, and by which we are conducted through another 
natural section of 5 a, b and c, and apparently out, right 
upon the beds of Devonian shales. At the base o the mountain, 
however, from the gap of which we have just issued, 7 and 8 
are concealed from view, as evinced by the fact that they crop 
out at many points along the base of the mountain at some dis- 
tance from the road on both right and left. In this Little , 
Goshen valley there are indications of extensive beds of limon- 
ite ores, some of which were worked many years ago. They 
are found in both 5 8, ¢, and in 8. _ : 
This valley offers no special facilities for studying the Devon- 
ian shales, which are found much more fully and favorably 
exposed farther west, but along its western border for a distance 
. ‘ 
