640 — GEOLOGY OF OHIO. 
contained renders it improbable that the use of these waters can do . 
much harm. 
There are several springs of unusual volume in this district. The most 
notable is one well known through the whole Sunfish valley as the “ Big 
Spring,” or ‘‘Campbell’s Spring.” It is without doubt the largest spring 
in south-western Ohio. It is universally believed in the neighborhood, 
and, apparently, on good grounds, that a mountain stream called “ Dry- 
bone,” which disappears abruptly from its bed two miles to the westward, - 
emerges again as Campbell’s Spring, its waters having been cooled, clari- 
fied, and re-enforced by their subterranean journey. It is claimed that 
the water has been tracked through the mountain that intervenes by 
bran or chaff, which was thrown into the stream, and which was found 
again in the spring. There is reason to believe that the spring has more 
than one principal source. : 
An attempt was made a year or two since to alaas this strong and 
steady stream of water by making it turn a mill-wheel. To secure the 
necessary “head,” a heavy wall was laid in cement around the spring; 
but the water rose only four or five feet before it burst out from the side ) 
of the mountain a few rods to the northward of its old point of emere- 
ence, thus rendering the enterprise fruitless. 
2. No valuable springs occur in the black slate series. Indeed, there 
is no geological formation in the State that furnishes water of as poor 
quality and in as inadequate supply as this. ‘“‘Seeps” rather than 
springs occur at infrequent intervals in its outcrops, but the water is 
mineralized to such an extent as to be unfit for use by man or beast. 
Wells are, in like manner, impossible or unprofitable in this formation, 
the quantity or quality of the supply, or both, being objectionable. 
3. The frequent courses of shale that occur in the Waverly series 
prevent water from entering or passing through it to any great extent; 
and this great division of the rocks of the county must, therefore, as a 
whole, be set down as poor in water-supply. Where some of the sand- 
stone strata—as, for example, the Waverly quarry courses—are exposed 
for any considerable area, springs of pure water mark the outcrop of the 
first underlying seam of shale; but there is no considerable line of 
springs to be referred to this horizon, nor, indeed, to any other horizon in 
all of the series. What few springs occur are generally of fair quality, 
but of light volume, and, for the most part, fail during the heat of sum- 
mer. ) 
The Waverly table-lands, of which extended mention has been made, 
are especially defective in natural water-supply. The weathered prod- 
ucts of their rocky floor generally form a compact and fine-grained clay. . 
