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.UNIVERSITY)] 

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HENRY COUNTY. 



pact, or dark-colored limestone, having a nodular or concretionary ap- 

 pearance. The whole rests on several feet of compact, hardened car- 

 bonaceous mud. But the most curious deposit in this interesting 

 locality is a thin stratum of " cone in cone," outcropping in the yellow 

 clay, several feet above the top of the sandstone. The stratum is from 

 two to four inches thick, has a woody or fibrous texture, the grain run- 

 ning vertical to the plane of stratification; on being dug from the 

 ground it falls into small blocks, haying the appearance of wood split 

 from a thin section of a large tree. In one or two of the low, rain- 

 washed hills in that vicinity, I noticed this same outcrop, with no signs 

 of the underlaying rocks. Large quantities of this "cone in cone" have 

 been gathered up for cabinets. Its resemblance to petrifactions of wood 

 is very complete. 



The Coal Seams. In the north-western part of the county there is 

 one heavy coal seam, well developed, and worked to a large extent. In 

 the south eastern part of the county, and extending up through its 

 central portion, there are two seams, the lower of which is largely 

 mined. Commencing with the former, and at the outcrop highest up 

 Eock river, within the county limits, we find ourselves at Aldrich's 

 mine, on section 24, township 18, range 2 east. The coal is here about 

 four feet six inches thick. It is overlaid by a few inches of dark shale, 

 and this is in turn capped by the thin stratum of black limestone, spoken 

 of above. A bed of ordinary fire clay lies under the coal. The mine is 

 opened into the point of a hill, up a wooded, romantic ravine, about 

 one-half mile from Eock river, which here washes the base of the bluffs. 

 A steam engine pumps out the water, and draws the coal cars up an in- 

 clined plane. The drift extends toward the south at a heavy dip near 

 its opening. The mine has been worked for many years. The coal is a 

 bright, moderately hard, thin-seamed coal, with carbonaceous clod be- 

 tween the seams, and vertical markings of carbonate of lime in the per- 

 pendicular openings. The following analysis shows its composition. 



Specific gravity 1 261 



Loss in coking ; 43. 1 



Total weight of coke 56 9 



100 



ANALYSIS : 



Moisture 6.0 



Volatile matters 37. 1 



Carbon in coke , 49 9 



Brown ash 7.0 



100.0 



This analysis was made for the State by Mr. PRATTEN, I believe, auTl 

 gives the general character of the coal in the north-western part of the 

 county. An approximate, section at this coal mine gives about the fol- 

 lowing figures : 



