580 GEOLOGY OF OHIO. 



A sample of the lower cement limestone taken from near Henry Wind- 

 land's Mill was analyzed by Professor Wormley, with the following re- 

 sult: 



Silicious matter 20.90 



Alumina and sesquioxide of iron 6.10 



Lime, carbonate 44.00 



Magnesia, carbonate 29.02 



Total 100.02 



This limestone has a handsome appearance, and with proper treat- 

 ment should make a good cement lime. 



The iron ore found in the red shales west of the town is very pure 

 and excellent, as will he peen from the following analysis by Professor 

 Wormley : 



Specific gravity 2.900 



Water 2.00 



Silicious matter 13.28 



Iron, sesquioxide 77.11 



Alumina 4.40 



Manganese 0.40 



Lime, carbonate 1.79 



Magnesia, carbonate 0.30 



Sulphur 0.06 



Total 99.34 



Metallic iron 53.98 



Phosphoric acid trace. 



This is scarcely a hydrated sesquioxide or limonite, the percentage of 

 water being only 2. The iron made from this ore would be admirably 

 adapted to the manufacture of Bessemer steel. 



At Stead's Mill, section 27, the following geological section was taken : 



rt. In. 



1. Crumbling limestone, somewhat magnesian 2 



2. Interval not exposed 148 



3. Sandstone 10 



4. Shale 5 



5. Sandstone 1 



6. Coal 2 



7. Black bituminous slate 3 



8. Coal 2 



9. Shale ! . 6 



10. Coal 1 



11. Clay 3 



2. Coal 6 



(Map Xni., No. 9.) 



