HURON COUNTY. . 301 
BEREA GRIT. 
This important quarry rock covers much of the county, but its value 
is greatly impaired by the local disturbances mentioned above. 
At Rattlesnake Run, in Norwalk township, an exposure of the Berea 
and the rocks below gives the following sections: 
~ 
. Drift, with fragments of Berea Grit. 
. Black shale, containing a 
mass of Berea Grit ...... 30 feet 
MBinelshalers yee itameer. 1 ‘ 
14. Black shale.........- Wate '2 “ (Cleveland 
“i Bluershalews eee ee ee 6 ‘ { gshale. 
iBlackishaleseseeeeeee eee Q 
HUMETICISNALOS cise ee Bp & 
. Blue argil. shale, with hard bands. 
=| 9. Huron shale. 
Here the Bedford shales are entirely wanting ; the Berea grit is crushed 
and broken, and rests in a narrow trough of the Cleveland shales. This 
is not an old channel, cut out before the deposit of the Berea, but was 
excavated by a part of the Berea which in a measure resisted the crush- 
ing force of the ice, and was pushed forward by it, until it had excavated 
the channel in which it now rests, dipping southward 30°. The Cleve- 
land shales on each side immediately adjoining the Berea, dip toward it, 
but at a short distance from it dip in the opposite direction, showing that 
they were pushed outward and “buckled” slightly upward by the lateral 
pressure. 
At Jefferson’s quarry, near the town line at the north-east corner of Town- 
send, on a long ridge running north and south, the surface of the Berea 
is two hundred and seventy-five feet above the Lake; the dip is south- 
westerly 17°; the line of strike north 67° west. The upper layers only 
are exposed; these are thin, but strong, and less broken than in most 
places in the county, indicating that here good quarries could be opened. 
A half mile further north, the dip is 15°; the surface marked with glacial 
strie, bearing north-east and south-west At Mr. Milliman’s quarry, near 
the north-west part of Townsend, the dip of the Berea is 20°. South and 
south by south-west the stone is of good quality ; glacial striz north-east 
and south-west. Hast of the last two exposures, and on the east bank of 
the Vermillion, the surface of the Berea is twenty-five feet below the 
last. Fifteen feet of the rock is exposed in large massive blocks, nearly 
horizontal, but dipping slightly in different directions. These blocks 
