SANDSTONE, SHALE, AJSD COAL. ii.S 



and shale, covered up by the slip, may occupy another 100 feet, or 

 upwards ; making the whole thickness of the strata, above the level 

 of the sea, about 500 feet. 



In some parts of the sandstone bed No. 5, there are quantities 

 of calc spar in the fissures or crevices. Some of the crystals are of 

 the long pyramidal form, called dog-tooth spar; and are highly 

 transparent, with a yellow tinge.. Aggregated masses of such crystals 

 ,|ire sometimes found in fissures or cavities, with their bases adhering 

 to one side of the fissure^ while their diamond points, crowded 

 together, form a curiously indented surface. Similar aggregations 

 occur in the fissures of the oolite, and of the beds immediately 

 beneath it. It may be questioned, whether the calc spar of this 

 sandstone, has originated in the calcareous matter belonging to the 

 stone itself, or in what has descended from the limestone above it. 

 The latter is the more probable, as the same kind of spar is found in 

 some of the fissures of the limestone itself. 



The beds below No. 11 consist of an alternation of sandstone 

 and shale, with a small portion of coal and of ironstone. This lower 

 part of the series may be seen immediately beyond the termination of 

 the Stainton slip, particularly at the point where the great bed of alum 

 schistus first makes its appearance. The beds of arenaceous and 

 bituminous shale are perhaps more numerous at this spot, than at 

 any other which the authors examined. Between twenty and thirty 

 beds, or seams, may be counted in the front of the cliff, alternating 

 with sandstone of various kinds ; the large beds mentioned above 

 being here subdivided. 



The transition of sandstone into shale, or of shale into sand- 

 stone, so common in this part of the strata, is sometimes sudden^ and 

 sometimes very gradual. In general, where the shale passes into 

 sandstone, we first find seams of sandstone running into the shale, 

 and these seams gradually thicken, till the shale is completely thrust 



