194. GEOLOGY OF OHIO. 
ing through the fissures in the limestone, has worn the rock into irregu- 
lar shapes. Throughout this distance the bed is cut up by many clay 
“horsebacks,” thrust up from below, while the coal is so crushed and dis- 
torted as to be utterly worthless. The shaly layer, No. 7, is much slick- 
ensided, and No. 10 is a mass of slaty, slickensided material, which is not 
removed. The upper coals, Nos. 3 and 5 of section, are good and clean, 
showing little tendency to run, and bear a decided resemblance to the 
Briar Hill Coal. Nodules of pyrites occur in these layers, but are not 
large or numerous, and are easily separated. The black shale, No. 7, 
which is quite compact, has thus far proved a very serious drawback, 
maintaining a thickness of seven inches along the entry, which, when 
visited, had been driven one hundred and fifty yards. It seems, however, 
to diminish eastward, being only three inches thick in a room opened in 
that direction. No. 8 seems to be of good quality, but shows a decided 
tendency to cake upon the fire. Specimens from this bank give the fol- 
lowing upon analysis: | 
UPPER BENCH. LOWER BENCH. 
Specific gravity..-... HBAS Se SUS HAD on a AHS OBaSOsbICau bc Sooo lente 1.285 
IM GISUUNC) Cire rctN ete ote ie evens Sctenanote sa oickaa rar Sey shel tec yy ert ee 2.30 2.90 
Aghia i Be Loe ie ae ising Ne oie. ladarhatartenaya stare pe aye ae 4.90 6.60 
Volatileycombustiblehinattersees ese scare eee eee eee 30.90 36.70 
EXC OL CAT DOM beer erterrcicte Clee ere EN Sata foe tren Sete 56.90 54.20 
Wh 2) Pee eee ier ae Ce Aes RA NEAR EO HA nH eae acee 100.00 100.00 
S ull pla vir eee ele reereee este e betta toncaiatete tet arate tes yal Stata iate oer teat 2.03 2.33 
Sulphurleftpm coke ete ses le eae fee eve erate epee meena ~ O8s 1.01 
Suliphurtonmmimnc.otechercokce ee eeee eee eee eee eee 1.58 1.66 
Hixedtcasiperspoundssinicubichee tees pee eee eeeeaneeeee 3.40 3.48 
Ashi: ile, 0e ese care Rie Cee 2 See eee ae saa eee White. Gray. 
COR Cee Ck Eee ete ou ctois elneatava ete arate ee Compact. Compact. 
In prospecting to determine the value of Coal No. 4, Messrs. Tod, 
Stambaugh & Co. made a number of borings, placing the work in charge 
of Mr. John Young. A table of the sections exhibited is given on the 
opposite page. These sections afford an interesting view of the changes 
which strata undergo within very limited distances. The whole area 
represented is about one hundred acres. Throughout, Coals Nos. 5 and 
4 maintain the same interval, or nearly so, showing that the disturb- 
ance, whatever it may have been, causing so marked variations in the 
distance between 4 and 3, must have occurred before the deposition of 
the rocks overlying the latter. This case is very similar to one reported 
by Mr. Read in Vol. I., page 498, showing that the rate of subsidence was 
not equal in all parts of the coal field, or even within limited areas. 
