- HURON COUNTY. 299 
bling in all respects the heavy clay lands in north-eastern Ohio, which 
are underlain by the Cuyahoga shales. Large elms are also a character- 
istic of the forests here. This surface, though apparently level, slopes 
uniformly and somewhat rapidly to the north, so that at the northern 
part of the township it is only three hundred.and eighty-five feet above 
the Lake. The indurated rocks are here deeply buried beneath the 
~ Drift which fills the broad, deep channel formerly connecting Vermillion 
River with the head waters,of the Mohican, and Ashland county. 
Qo 
GEOLOGICAL STRUCTURE. 
The geological structure of the county is easily made out, and com- 
prises simply the Upper Devonian and the Lower Sub-Carboniferous 
rocks, of which the following is an approximate general section : 
HT. 
eC ry anc aishal escapee sce Masel yatta stateielsia o/eiataloies a) ee) = = 100 
Pein d BIE) ELE NG AN Tees part alle ce We ot ME as SU cee Mee Ca ES Ae ave ea 50 to 75 
Bedford shale..-...---.---------- SSRN eo al eee Gat nate 40 to 50 
Cleveland anale Ay Bs sar VRE A a AMA NAL IBN Lee babes s 15 to 30 
WUE) IESE alow ee are eae Hoe Uber ch aoe abs pb a nib SSeael) 5 15 to 32 
FELTAP OTS Leal Oy Naot sae net ah Ammeniae ee te cas as eet Mes Aa Syl) Se 700 
See 7. Hamilton group... ++--++---4-++e0+2e2eeee ee ee ee eee 10 to 15 
PTY xX xX. XX XE! 8. Corniferous limestone - 50 
BGS GG: Gw Gas 
The exposed strata show evidences of much greater disturbance and 
displacement than I have observed elsewhere in the State. Sharp syn- 
clinal and anticlinal axes are visible in a majority of the rock exposures 
above the Huron shales. .These are most conspicuous in the Berea grit, 
and will be more specifically described in connection with that deposit. 
CUYAHOGA { HALES. 
- About one hundred feet of the lower part of the Cuyahoga shale under- 
lie the south-eastern part of the county.. This. formation is frequently 
exposed in the banks of Vermillion River and its tributaries, where the 
harder layers are quarried for local use, and furnish building stone of 
fair quality. The rock is a compact, fine-grained sandstone in rather 
thin strata, containing what the quarrymen call turtle-backs. These show 
contorted lines of cleavage, which cause the rock to break up in rounded, 
flattish masses, bearing a rough resemblance to the animal which has 
