WARREN COUNTY. 385 



sand. The courses overlying these beds are enabled by their chemical 

 composition, as it appears, to resist the action of fire to a good degree, and 

 are accordingly known a,?, fire stone. The general composition of the group 

 can be seen from the appended analysis : 



Carbonate of lime 85.21 



Carbonate of magnesia 13.56 



Alumina and sesquioxide of iron 0.80 



Silicious matter 0.35 



99.92 



This portion of the series serves a very useful purpose in this respect. 

 Chimney jambs manufactured from it have been kept in constant use for 

 fifty years without being defaced. 



The fossils of this series are also very interesting. Mention will here 

 be made of only one — a unique specimen obtained from the Burnett farm, 

 near Waynesville, and now in possession of Israel Harris, Esq., of this 

 place. The fossil is probably a fucoid or sea- weed, but it simulates in its 

 mode of growth, especially in its branches, land- plants, none of which have 

 yet been found as low in the rocks. It has been described in the trans- 

 actions of the Lyceum of Natural History of New York by Dr. Newberry 

 as Fucoides Harrisi. 



The thickness of the Clinton limestone in the county does not exceed 

 twenty feet, and falls below this in an included section measured on the 

 farm of Dr. William Stokes. 



All of the characteristics of the line of junction of Lower and Upper Silu- 

 rian, described in the report on Montgomery county, are to be observed in 

 the exposures of this line in Warren county. A small outlier of Clinton 

 limestone that occurs on the east side of the Miami, near Freeport, deserves 

 mention in this report, though place could, perhaps, more appropriately 

 be found for it under the head of the glacial agencies shown in the county. 

 The outlier has been known from early days in the neighborhood as the 

 Betty Heidy quarry. It embraces about three-fourths of an acre, and is 

 about sixteen feet in thickness. The peculiarity of its history is that it 

 has been transported to its present position bodily from some adjacent 

 locality. It is marked upon the map as outlier C. It overlies drift ma- 

 terials, such as glacial clays and gravel, and is one hundred and twenty- 

 five feet below the elevation required for the formation at this point. 

 There is no evidence whatever of any dislocation of the strata generally 

 at this point, and we are compelled to regard it as a gigantic bowlder, 

 transpo'-ted from the opposite side of the river by the great glacier which 

 occupied Southern Ohio in the earlier stages of the Drift period. Accord- 



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