670 GEOLOGY OF OHIO. 
thin-bedded, yellowish shaly limestone. The shale is much the more 
constant and abundant of the two, the limestone layers coming in as a 
rule near the bottom of the series, at the same horizon where the Dayton 
stone is found when it occurs. In other words, the Dayton stone, in excep- 
tional instances, replaces these shaly layers. The last named phase of 
the formation is shown very distinctly in the section on the Grinnell 
pike. The composition of the shale proper is shown by the following 
analysis, made by Prof. Wormley : 
Carbonate of lime ............ Baa SEdEOHEOSbOKON adododbo9 aaGGaD6ee SoHE HOSES bdodboSd8 aoDNKERD 34.40 
Carbonate of iMaASNesla ery. eell eee eakae wae eetetiee cee ea eee ae eee aaa EE renee 30.87 
SUTEATSTORS IMSL rah cossieswagesea te seloce vatecson cu Setetctelie ale See aeee sean SUN URe aoa eee a ane mene a 8.48 
VAT WMATA NATIVE AOI CSA rooeees wn ee snlesea was nem ee Nae els eae eae Lae ER ae a 8.40 
DUD CAM eet sccaes se someules oo vies ste e cae cles tee seater siete utaisorn setae tacete Re ere aca n el NaN RE 12.21 
WiatOry) COMMDIMCA ie csiese conor cduece ecesos cece cee u lees senee ae Coc ee OI See a cL ae naan 5.40 
99.78 - 
There are occasionally found in the shale numerous crystals and nod- 
ules of sulphuret of iron. In some of the sections shown in the Glen at 
Yellow Springs such nodules abound. They are often construed, by the 
ignorant as indicating mineral treasures in the rocks which are here 
shown. A pit near the mouth of the Cascade Branch, six feet in diam- 
eter, and certainly more than twenty feet in depth, walled with timber, 
and now partly filled with rubbish, the origin of which j is unknown to 
the oldest inhabitants, seems to show that such deceitful expectations 
were awakened in the minds of the earlier occupants of the country. 
Such unsuccessful experiments serve to show that our predecessors knew 
less than we now know of the contents of the strata, rather than more, 
as the credulous sometimes believe. The excavation was carried down 
into the Clinton limestone, the whole thickness of which might have 
been seen and studied by passing down the valley for half a mile. 
The surface of the Niagara shale is a very important water-bearer for 
this whole region, giving rise to a line of strong springs along its out- 
crops, and supplying the largest number of the drilled wells of the Malnle: 
land. More extended mention will be made of this subject in a subse- 
quent part of this report. . 
(c.) The next element in ascending order is the formation termed 
in the report on Highland county the West Union Cliff. This stratum 
would certainly not be erected into a separate division from any facts in 
its occurrence in this part of the State; but in Adams county it attains 
a thickness of ninety feet, and constitutes, in several of the southern ~ 
counties, a very marked and important element in the Niagara series. 
_ In Greene county, as in Clarke, it does not exceed eight feet in thick- 
