No. 50.] 
243 
1. Fossiliferous limestome like the middle limestone of Be- 
craft's mountain," 60 feet. 
2. Fossiliferous limestone, different from the above, and con- 
taining hornstone, 50 
3. Compact dark gray limestone, (pentamerus,) 34 
4. Clouded striped limestone, 20 
5. Cement rock, (grsiy,) - 2 
6. Compact black limestone, 1 
7. Cement rock, (gray,) four strata, 12 
8. Black coralline limestone, (various radiaria,) 8 
9. Cement rock, (gray to black,) .... 8 
10. Limestone, dark coloured, impure and fossiliferous, .... 8 
Thickness of the limestones and cements, - 203 feet. 
11. Hudson slates and grits, thickness unknov^n. 
At the extreme southwest end of the hill, the strata are much de- 
ranged and bent, but a little farther east, at the quarries, and along the 
face of the cliff, they are finely exposed, dipping at a moderate angle to 
the east-southeast. 
There is an anticlinal axis along the broken ridge betv^^een the Eso- 
pus creek and the Rondout. The rocks on the northwest of this axis 
dip to the west-northwest, at a small angle conformable to the general 
dip of the rocks which overlie them on the northwest side of the valley, 
and which do not appear to have been much disturbed by the upheaving 
action that has dislocated and upturned all the rocks east and south of 
this valley. On the southeast of this axis, the strata are broken and 
upheaved, dip to the south-southeast, at angles from 20° to 80°, and 
present successive mural escarpments. There are several anticlinal 
lines, and lines of fault parallel and subordinate to the main one. One 
passes through two small lakes in Marbletown. A high mural preci- 
pice originating in a fault passes along the east shore, while two long 
promontories with arched strata stretch far into the lake from its extre- 
mities. The same continues to the other pond, and the continuation of 
this fault and anticlinal axis is easily traced thence by the eye over the 
whole line of hills, to the summit of the Shawangunk mountain, ranging 
south 15° to 20° west. This line of fault continues south-southwest 
by Flint's quarries, between which and Bridgeport, it forms the high 
mural'scarp of mountain on its west side, thence across the country 
from Bridgeport, with mural escarpments, to a high cliff on the Shawan-^ 
gunk. 
