Mr. N. Wood on the Geology of Northumberland, SCc. 317 



yards from the Dykes. In this Coal-field the distance which even 

 the lowest Coal-beds extend from the Dykes does not exceed 400 

 yards ; except when kept in by the accidental occurrence of branch 

 slips, or casual elevation of surface. These patches of Coal are, as may 

 be expected, considerably disturbed and affected by cross shps, branch- 

 ing out from the Main Dykes } and it is, therefore, difficult to identify 

 the different beds with each other. The following beds have, however, 

 been cut through in this district. 



1. Coal, inferior in quality, 

 Strata of Sandstone, and Shale, 



2. Yard Coal, 



Sandstone and Shale, 



3. Three-quarter Coal, 

 Sandstone and Shale, 



4. Main Coal, 

 Sandstone and Shale, 



5. Coal, from 13 inches to 

 Sandstone and Shale, 



6. Little Coal, 

 Sandstone and Shale, 



7. Stone Coal, 



The quality of these Coal-beds resembles those of the lower beds of 

 the regular Coal Measures, one seam in particular, the Yard Coal, is of 

 similar quality to one of the Wylam seams, producing Coke suitable for 

 reducing the lead ores ; a quality which none of the beds in this district, 

 except those belonging to the regular Coal Measures, possess. 



The real position of this Coal-field in the series is proved by the 

 absence of all Limestone beds above the Coal ; and, as will be shewn 

 hereafter, by the occurrence of thick beds of gritty Sandstone, resem- 

 bling Millstone Grit, underlying the Coal, and resting on beds of 

 Limestone, which will be traced as belonging to the first beds of the 

 mountain series. 



Beyond the vale of the West Allen, these seams are again found upon 



Fa. 



Ft. In. 







1 9 



10 











2 8 



4 



3 







2 8 



4 











3 8 



7 











1 8 



4 



3 







1 10 



3 



3 







1 8 



36 



11 



