228 GEOLOGY OF OHIO. 
vated in the Drift to the depth of fifteen to twenty-five feet, the limestone 
ridges and knolls constitute the only diversity of surface. These ridges 
produce gentle upward undulations of the surface, extending sometimes 
two or three miles, usually exposing the rock, and rising from five to fif- 
teen feet above the general level. In traveling over the country they 
are hardly perceptible to the eye, and are first revealed by the occurrence 
of stones and small bowlders on the surface of the Drift. Such limestone 
ridges are most frequent in the township of Clay, and the rock is exposed 
on sections 4, 9, 16, 28, 27, and 54. The rock is also exposed in a similar 
way in Benton township, sections 14, 23, and 26; also in Harris town- 
ship, section 14. In the bed of the Portage the rock may be seen through 
most of the township of Harris. In addition to their flood-plains, the 
streams have one general terrace, or bench. The former consists of such 
deposits as the freshet stage of the stream is not able to carry away. In 
it are imbedded vegetable remains—leaves, branches, and trunks of trees. 
The mass of the deposit is, however, a loose but homogeneous marly sand. 
It is also liable to contain stones of considerable size, the result of stranded 
ice In spring time. Its height along the Portage is, in Ottawa county, sel- 
dom over six feet above the summer stage of the water, dependent some- 
what on the obstructions to the current. The latter, or the first terrace 
above the flood-plain, is simply the result of the erosion of the stream, and 
shows the original condition of the Drift deposit. Its height, owing to 
the evenness of the original surface, is not apt to vary much, and is sel- 
dom over twenty-five feet. The changes of the stream from one side to 
the other of its flood-plain sometimes cause the union of these two ter- 
races in one; in such cases the entire bluff may be thirty feet Such 
banks may be seen in the township of Harris, sections 8 and 9, and at 
numerous other points. 
Character of Soil and Timber.—The soil is clay, with very few superficial 
stones or bowlders; at greater depths it contains some gravel and bowl- 
ders—the residue untransportable by water—which may be seen in the 
beds of the streams, and which are met in wells. There are also superficial 
deposits of sand, not only along the immediate beach of Lake Hrie, but at 
points several miles from the Lake. They are far more infrequent, how- 
ever, than in Wood and Sandusky counties. This cold and tough charac- 
ter of the soil, together with the difficulties of local drainage arising from 
its general flatness, has impeded the settlement of the county. By the 
aid, however, of the recent genera] drainage law, the whole county is 
being rapidly subjected to an excellent system of artificial drainage, 
and the soil is not only sooner relieved of the surplus of standing water 
in the spring of the year, but it is brought into an arable condition as 
