264 
exposure of knobstone and in the other an exposure of limestone, the line 
of contact coming somewhere between these two ditches. 
Farther south, in section 1, township 3 north, 2 east, occurs the same 
unconformity. From the road through the west side of section 1 to the 
line of parting in Clifty Creek is a descent of 150 feet. In going east to 
the head waters of one of the side branches of Rush Creek there is only 
a fall of 50 feet to the line of parting. The two points where the line of 
parting was observed are not over one-half mile apart. 
Farther north, in 5 north, 2 east, the limestone occurs on the west side 
of Guthrie’s Creek. The line of parting is 25 feet above the creek bed, 
and from the line of parting to the top of the hill is 100 feet. All the 
exposures are limestone. 
Near the top of the hill there is exposed a thick ledge of limestone 
which forms a small cliff corresponding to the cliff on the west side of 
Twin Creek. Farther west, where the streams have cut through the 
limestone and exposed the edges of the strata, no such cliffs are formed. 
Farther west the lighter the deposit for one-half mile or more, where it 
begins to thicken and dip gently to the west. A cross-section of the body 
of limestone is triangular in shape, with the base jutting against the knob- 
stone, the altitude along the surface and the hypotenuse bedding upon the 
knobstone. (Fig. 2.) 
Farther north, near the center of section 10, township 9 north, 1 east, 
the division between the knobstone and limestone crosses the road about 
150 yards west of where the road turns to the north. The knobstone does 
not occur in the hill to the east, although this hill is 50 feet higher than 
the road. In a gully 250 yards northwest of the road, where the line 
between the pale-colored clay of the knobstone and the red clay of the 
limestone crosses it is the line of contact between the two formations. 
One hundred yards southeast of the center of the southwest quarter of 
northeast quarter of section 10 the displacement is found. (Fig. 1.) 
In general this belt of limestone seems to extend north and south, or 
north 10° west, and has been observed from near Mount Carmel, in sec- 
tion 1, township 3 north, 2 east, Washington County, to near Unionville, 
in section 10, township 9 north, 1 east, Monroe County. 
At all points of observation the limestone had the same general shape— 
thick on the east side, with but slight modifications in going west for a 
short distance, then gradually thinning out, and connected or disconnected 
with the limestone west of it. 
