118 



may be made as regards the Coal Measures generally. For in 

 consequence of the unconformity of the overlying Permians to the 

 Carboniferous beds, the St. Bees Sandstone may rest on Upper 

 Coal Measures at a given place — Aspatria, for instance — and three 

 miles northward on beds altogether below the Coal Measures 

 (Fig. i). Again, as we go north of the boundary we may expect 



Jl Spain a. 



to meet not only with a greater thickness of St. Bees Sandstone, 

 but with the Gypseous Shales, and probably with a thicker covering 

 of drift. And though the Gypseous Shales may come on gradually 

 above the St. Bees Sandstone, it is by no means improbable that 

 their southern boundary is a line of fault, with a downthrow to the 

 north, ranging nearly parallel with that which bounds the Permian 

 formation, and with that which, still further south, brings in the 

 Coal-Measures between High Hall and Gilcrux (Fig. 2). For 



JfspaA:ri.a 





FloX. 



though we have no evidence of the existence of any fault bringing 

 in the Gypseous Shales (as we have in the case of the lower 

 formations), yet considering the known tendency in the leading 

 lines of fault in a district to take certain prevalent directions, one 

 is by no means unlikely to exist. And the consequences of boring 

 on the wrong side of a fault are somewhat discouraging and calcu- 



