ALLEGHENY FORMATION IN OHIO 115 



variations in ash and sulphur. The underlying clay retains its impor- 

 tance, is often non-plastic, and is utilized in manufacture of firebrick. 

 The interval to the Middle Kittanning varies from 50 feet in the north- 

 ern portion to 20 and 30 feet in the southern part of the county. Near 

 Zoar, on the northern border, a cannel 1 foot to 18 inches is at 16 to 26 

 feet above the Lower Kittanning, but it is wanting southward. The 

 Middle Kittanning, as in Stark, is important and is the Coal 6 of central 

 and southern Ohio. It is from 3 feet 6 inches to almost 6 feet thick, 

 and, while varying somewhat in quality, it is usually good, always 

 caking, though generally containing too much ash for a good merchant- 

 able coke without washing. As a rule, it is double, with a copperas band 

 at about a foot from the top. The roof is a black shale, often carrying 

 "large calcareous nodules or concretions, filled with beautifully preserved 

 Coal Measure fossils" and at times becoming bony cannel in the lower 

 portion. The bed identified with the Lower Freeport is indefinite and 

 the accuracy of the correlation is open to question, at least for the north- 

 ern part of the county. The Upper Freeport is persistent, rarely yields 

 good coal, and is double, the parting varying from 8 inches' to 15 feet. 

 This characterizes the bed in Guernsey county. 



The Vanport limestone reappears in many sections and is fossiliferous; 

 it is seen occasionally midway in the county, but more commonly in the 

 western portion, where the Lower Kittanning coal bed is wanting.* 



Guernsey county, south from Tuscarawas, shows the whole iUlegheny 

 section in the western portion. The Upper Freeport coal bed is 200 to 

 255 feet below the Ames limestone. The Cambridge limestone of the 

 Conemaugh becomes characteristic here and is an important stratigraph- 

 ical guide southward. Professor Orton's section in northwestern Guern- 



Se y 1S: Feet. Inches 



1. Cambridge limestone 2 



2. Interval Ill 



3. Upper Freeport coal bed [Cambridge] Thin 



4. Clay, Upper Freeport limestone 10 



5. Interval 50 



6. Lower Freeport coal bed Thin 



7. Interval 100 



8. Middle Kittanning 3 



9. Fireclay and shale 30 



10. Lower Kittanning 2 6 



11. Fireclay 20 



12. Interval 16 



13. Putnam Hill limestone 4 



14. Brookville coal bed Thin 



* J. S. Newberry : Vol. iii, pp. 61-62, 64-66, 67-70. 

 E. Orton : Vol. v, pp. 92-93, 268, 274, 279, 282. 



