470 GEOLOGY OF OHIO. 



we consider the large extent of surface, which rises above the .place of 

 the springs, upon which falls throughout the whole year about thirty 

 inches in perpendicular height of water, in the form of snow or rain, 

 and the suitable character of the deep Drift and porous rock for absorbing 

 and retaining this, to be yielded gradually, we need not be surprised at 

 the quantity of water which flows from these springs. The surprise, 

 which is often expressed, has not been at the absolute quantity of water, 

 for this is not great compared with many other springs, but at the quan- 

 tity which should issue from a locality which seems to be so near the 

 general level of the country immediately in the vicinity, whence the sup- 

 ply must apparently come. But the supply may be drawn, as I have 

 endeavored to show, from a much greater distance than we might at first 

 suppose. 



Wells. — Where there are no springs, water is readily obtained by sink- 

 ing wells, either in the Drift or solid rock. The sinking of wells is a 

 means of exploring the earth to a moderate depth, and some interesting 

 facts are often obtained by inquiry into the character of the material 

 penetrated. For example, in some places in the county no wells have 

 ever penetrated beyond the Drift, or, at least, reached bedded rock ; while 

 on each side, sometimes at no great distance, other wells have to be sunk 

 in the rock. Generally, perhaps always, it will be found that a line can 

 be marked out by such excavations, within which no rock is ever reached 

 by the deepest wells, while the excavations on each side show bedded 

 rock near the surface. Here, then, we have traced for us the channel of 

 some ancient water-course which has been filled in with Drift at some 

 time in the past. There were rivers, and a river system, cut far deeper 

 in the rocks of a former age than any we now have in this region. The 

 whole surface was sunk down under deep water and gravel ; sand and 

 clay covered up all inequalities of surface. When the surface emerged 

 again, the drainage began to excavate channels, the general character of 

 the surface remaining the same; the streams would take courses in 

 general the same as before, but from local causes would be deflected in 

 places. The old, filled-up channels are now traced by means of excava- 

 tions. I will mention that at Mr. Murray's, on the Troy and Covington 

 turnpike, no bedded rock is found in sinking wells, while to the east, 

 within a half mile, and "to the west, stone in silu is encountered in well- 

 digging. 



The influence of the character of the surface on the soil can be noticed 

 in various parts of the county. This may be illustrated by comparing 

 the soil and surface on the east of the Miami River with that on the west. 

 East of the Miami the surface is rolling, and gravelly ridges abound. 



