616 GEOLOGY OF OHIO. 



in their composition; but the courses in question are almost the only 

 ones that attain this percentage. Their chemical relations are rather 

 with the beds below them, than with those above. 



No. 1. 

 Carbonate of lime 55.09 



Carbonate of magnesia 41.07 



Oxide of iron 63 



Silicious matter 1.96 



Organic matter 92 



99.67 



Analysis No. 2 appertains to the same horizon. The specimen wa 

 obtained from the quarries of the Roberts Bros., Jefferson township, Madi 

 son county. (Bank of Little Darby Creek.) 



No. 2. 

 Carbonate of lime 64.20 



Carbonate of magnesia 34.44 



Alumina and iron .00 



Insoluble matter 1.10 



99.74 

 Analysis No. 3 is of the rock that lies at the base of the Corniferou>s 

 limestone, at Bellefontaine. (Stevenson's quarries.) 



No. 3. 

 Carbonate of lima 56.40 



Carbonate of magnesia 41.46 



Alumina and iron 2P 



Insoluble matter 1.20 



99.29 

 For comparison the analysis of the Lower Corniferous, from Paulding 

 county, is appended. The stone here is very different in appearance from 

 any other in the series, being non-fossiliferous and quite fine and even 

 grained. The specimen analyzed is from Clark's quarries, Charloe. 



No. 4. 

 Carbonate of lime 57.09 



Carbonate of magnesia 33.14 



Alumina and iron 3.97 



Silicious matter 5.33 



Organic matter 88 



99.41 

 Nos. 5 and 6 are from the quarries of Smith and Price. The first ol 

 these represents quite favorably, the general composition of the most 

 valuable stone of the quarry — viz., the cutting stone, while No. 4' shows 



