COAL MEASURES. 



4 



6 : 



6 



6: 

 10 



10^ 



20 



Section of Coal Hill, Pittsburg, Pa. 

 Fig. 47. 



^ 1. Reddish brown argillaceous earth. 



2. Sandstone — slaty, fine-grained, 

 ash-coloured. 

 y//2 3. Shale — dark brown, carbona- 

 m ceous, slaty. 



;;-::vl 4. Clay — dark- coloured, carbona- 

 ceous. 



5. Coal — bituminous; supplies 

 the manufactories of Pitts- 

 burg". 



V 6. Clay — dark, slaty. 



1 



270 



7. Sandstone. 



8. Limestone — dark- coloured. 



;^ 9. Sandstone — light-coloured and 

 \ argillaceous, with impres- 



vV sions. 



10. Limestone — light-col'd, hard, 

 ^ compact. 



11. Sandstone — fine-grained, com- 

 pact, good building-stone. 

 Salt water is obtained by 

 boring through this rock. 



