16 Mr. Bubble's Notice of a Whin Dyke. 



the Tyne High Main Seam, as the standard, it Hes 100 fathoms deeper 

 at Benwell than at Walker. The course of this Dyke is in the Hne of 

 the full dip and rise of the strata. 



Note. Since writing the foregoing account we have again drifted 

 through this Dyke, at a point 144 yards further to the South East than 

 the drift described in the section, Plate II. In this latter drift the only 

 material difference which occurred in the Dyke, or its concomitants, was 

 that the Basalt was only 7 feet thick, being 6 feet less than in the former 

 drift. 



