ALUM SHALE. 153 



height; but soon aftei' descend to the beach, and the cliffs exhibit 

 nothing but alluvium, till we get beyond Newholm beck. Between 

 that beck and the foot of Dunsley lane, the dogger makes its appear- 

 ance in the cliff, with the alum shale below it, but scarcely any 

 sandstone above it. These strata gi-adually rise from the beach; but 

 at Dunsley lane they are suddenly discontinued. Beyond Sandsend, 

 they resume their course in the sea cliffs ; and, as we find them here 

 at such an elevation as they might be supposed to have reached, had 

 no interruption taken place, we may presume, that whatever subsi- 

 dences or breaks have produced the openings at the becks of East 

 Row and Sandsend, they have not affected the general disposition of 

 the strata. The two becks run parallel to one another for two or three 

 miles, parted only by the high and narrow ridge on which stands the 

 old castle of Mulgrave. The front of the ridge at Sandsend is 

 alluvial, but we find the alum shale in it, not far above the village. 



In the lofty cliffs beyond Sandsend, we not only find the alum 

 shale and its covering of dogger rising to a great height, but a consid- 

 erable thickness of the sandstone beds above them, often to the 

 amount of 50 or 60 feet. On the scar below, the lias seams begin to 

 appear, a little to the north of Sandsend alum house ; from which 

 circumstance we have named them the Sandsend beds. Beyond them 

 the eompact shale rises up like a wall ; and, as has been noticed, the 

 ironstone or Kettleness beds rise up at KettI en ess point. At that point, 

 the schistose beds rise to a great height; but the sandstone beds 

 above them disappear, or retire backward. 



Beyond Kettleness, the course of the strata is again interrupted, 

 at the back of Runswick bay. Instead of continuing to rise beyond 

 Kettleness point, the strata descend a little towards Hob-hole. There 

 a great portion of the upper strata have been washed away, while the 

 lower have partly subsided, at a small stream on the south side of the 

 cave. The cave itself is in the compact shale. Beyond it, the whole 



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