62 GEOLOGY OF OHIO. 
of Mr. Read, the base of this ridge is an old moraine of bowlder clay, and 
such may be its character; but, as will be seen from the section given 
below, taken at the point where the Ashtabula and Jamestown Railroad 
cuts through this ridge, its upper portion is stratified, and it is capped 
with beach sand. It seems to me more probable that it is a clay terrace, 
capped with a ridge thrown up by the shore waves. The old swamp, 
_ Section of Drift Clays, Ashtabula, 0. a 
LM 
ZLB 
z. Sandy loam, 1-2 ft. 
2 Yellow clay, with fragments 
of shale, ro ft. 
3. Blue clay, with fragments of shale 
and boulders, 14 ft. 
4. Fine sand—local, o-3 ft. 
5. Coarse gravel—coarsest at bottom, 
ro ft. 
6. Blue clay, with boulders, so ft. 
SS = 7. Erie shale in place. 
with its muck bed and buried timber, is the counterpart of others that 
are found behind the ridges in a great number of localities. Similar 
swamps may be seen behind the beach ridges now forming along the 
present shores of Lake Erie and Lake Michigan. 
Profile Section from Lake Erie to Grand River. 
os 
isl 
z 2 
(re) ie 
wi 
2 pom 
hi _ 
fe D wet \ @ yi 
La = Cc ———— \ 
< — —<s : 2 S m “Wo 
a A ae a 2 mt au N oO 
HORIZONTAL SCALE, 1 INCH TO 1% MILES. 
In his report on Lake county, Mr. Read gives a profile section of the 
lake ridges, with the following explanatory notes: 
‘In Madison township the slope from the Lake rises more gradually than further 
west, and the lake ridges are more regular and are better defined. The section given 
below reaches from the Lake through Madison Center to the bed of Grand river. 
