SUPPLEMBNTAL EEPOET — HANGING ROCK DISTRICT. 929 



thereof ot the tunnel. It can be traced distinctly for more than thirty feet. 

 The seam is numbered IIIc in the section, but it will be remembered 

 that the identification is not positive in the general review. 



The lodge of sandstone that lies next above is th'fe most marked of all 

 the deposits of this order in the Lower Coal Measures of the district. It 

 is finely shown on Hecla Furnace lands, and yields there furnace hearth- 

 stones that are w«ll approved. It can be followed through Lawrence and 

 Jackson counties into Vinton county, holding everywhere a thickness of 

 not less than twenty-five feet, and sometimes rising to forty feet. It is- 

 no where shown better than in Bloomfield township, Jackson county. Its 

 relation to the Gray Limestone renders it very easy of identification 

 throughout the field. It may very appropriately be termed the Hecla 

 Sandstone. 



We reach, now, the horizon of the Gray Limestone. It is five feet 

 thick at the point where the measurement was taken, but a heavier body 

 of it is found in some of the sections of the neighborhood. The place of 

 the coal seam that is so generally found below it, Coal No. IVa, is indi- 

 cated in the section, but there is not even a black line to stand for the 

 seam in the actual section. As in the Hocking Valley, so in the Ohio 

 Valley, the coal is wanting, while from the northern part of Lawrence 

 county to the north line of Vinton county, the seam is on the whole the 

 most stable and valuable of all the series. 



Over the limestone, one foot of ore is found, and over the ore, eight 

 feet of fire-clay. The clay is of the plastic variety, and has been largely 

 employed in pottery in past years. Its white color makes it everywhere 

 conspicuous in the sections of the region. 



Over it, about fifty feet of sandstone is found in two great ledges, which 

 are generally separated, however, by Coal No. V, the New Castle seam. 

 The upper ledge lies immediately over the coal, and the lower one ap- 

 proaches the coal very closely, also. Vertical sections, in which the 

 country abounds, often show the sandstone continuous, the coal being 

 entirely cut out. The New Castle Coal is, in the fronton hills, three and 

 one-half feet thick. Its quality can be judged in part by the fact already 

 noted that it has a sandstone roof. Such a cover is almost always asso- 

 ciated with a sulphurous coal. 



Above the upper ledge, the "Black Kidney" ore, as>it is named in some 

 of the Kentucky furnaces, is found. It lies from eight to fifteen feet be- 

 low the Sheridan Coal (No. VI) and is without doubt identical with the 

 Snow Fork Ore of the Hocking Valley. Like it, it frequently contains 

 impressions of fern leaves and other vegetable tissues. 



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