40 Prof. BucRLAND and Mr. De la Beche on the 



very short distance : the pseudovolcano we have described is in the Kim- 

 meridge clay which forms the base of this subsided mass. 



Another minor fault is seen at Boat Cove^ on the west of Osmington Mill*, 

 where an apparently false dip of the Oxford oolite has been produced by a 

 recent slip of the cliffs ; it is so small and partial that it would be unworthy 

 of notice were it not that it is prominently exposed in the profile of the coast, 

 and gives an erroneous impression of the position of the strata in the cliff 

 from which it has fallen. Near this spot, also, at the cascade of Osmington 

 Mill, we have another small fault, exposed on the shore traversing the Oxford 

 oolite, and running outwards into the sea, just along the anticlinal line, where 

 the strata turn at this part of the coastf . 



4. Bothenhampton Fault. 



PI. II. fig. 14. represents a downcast fault at Bothenhampton, one mile 

 south-east of Bridport. We believe that this fault was first noticed by Prof. 

 Sedgwick : it is of considerable depth, bringing the forest marble on its 

 south side into contact with inferior oolite on the north side, the forest 

 marble dipping at a considerable angle towards the fault ; its general range, 

 like that of the rest, is nearly east and west, and although, from the similarity 

 of the clays which it intersects, we have not traced its uninterrupted con- 

 nexion, we think it continues eastward to Shipton Gorge, Litton Cheney, and 

 Long Bredy. At each of these three places, lying as they do nearly on a 

 straight line, there has been much dislocation and disturbance. 



5. Bridport Harbour Fault. 



At PI. II. figures 13 and 14 represent the western termination of another 

 downcast fault in the cliffs about a mile west of Bridport Harbour, being the 

 last we have to mention. Its amount is considerable : on its north side are 

 beds of inferior oolite based on lias ; on its south side are beds of forest 

 marble based on more than 130 feet of grey clay, and these are suddenly and 

 violently turned up when they come into immediate contact with the fault. 

 We believe this clay to be the same that occurs in such thickness in the Vale 

 of Bredy ; and although we have there considered it as subordinate to the 

 forest marble formation, we have no evidence to show that it may not also 

 represent the Fuller's earth beds that occur between the great oolite and in- 

 ferior oolite of the neighbourhood of Bath. The eastern extremity of this 

 fault;}: presents a complicated double fracture, causing the lower beds of the 



* See Plate II. fig. 9. f See Plate II. fig. 9. + Plate II, fig. 13. a. 



