Introductory Views. - 5 



were much more rapidly accomplished than after that period. While 

 a part of the valley was yet covered with water, evaporation was 

 much more ahundant and the rains more hke those of tropical cli- 

 mates ; tearing up and wearing away the surface with great facility, 

 and ejffecting greater changes in the features of the valley in one 

 season, than can now he accomplished in many years. The roots 

 of the trees, and the plants, after they had taken possession of the 

 surface, giving firmness to the soil, and defending it from ahrasion 

 in the same manner that the trees, where they are suffered to stand 

 undisturbed by the officious interference of m.an, now defend the 

 banks from the encroachments of the Ohio. They not only pro- 

 tected the newly clo^thed surface on the hills; but in the valleys, and 

 near the beds of rivulets and brooks, when the streams overflowed, 

 they arrested the soil and fragments of rocks that were urged on- 

 ward by the turbid waters, and thus these periodical deposits gradu- 

 ally raised up the bottoms or alluvial soils, to their present height. 

 That this was actually the fact, and that the surface of the soil in 

 narrow vallies and bottoms, w^as once much below its present condi- 

 tion, is proved from the presence of wood and trunks of trees, found 

 at the depth of thirty or forty feet in sinking wells, shafts, fee. A 

 single shower has been known to make a deposit of several feet in 

 thickness on the borders of small streams. No longer since, than 

 the month of June, A. D. 1834, a few miles from Marietta, a cloud, 

 in the course of fifteen or twenty minutes, poured its watery con- 

 tents on the hills, to an average depth of eight or ten inches. No 

 accurate measure was taken of the water, but a half bushel measure 

 and a common pail, or bucket, in separate places, were filled to 

 overflowing ; and several rail fences on the sides of hills, were mo- 

 ved a number of feet by the column of water, rushing down their 

 declivities. Tn Licking and Knox counties, during the same season, 

 a much greater amount fell, doing great damage to the Ohio canal 

 and to mills on the small streams. If in these days, such torrents 

 fall, in places remote from any great collections of water, or from 

 ranges of mountains, what might they not have been, when this 

 great valley was one vast wet and marshy plain, affording an im- 

 mense expanse of watery surface to evaporation. 

 - At what period after the creation of the earth, this change, from 

 an ocean to dry land took place, we have no data to determine ; 

 but it is not impossible that future geologists may, by their research- 

 es arrive at some tolerable approximation. That the change was 



