228 Geology. 



sides, runs up to Freshford and Limpley Stoke, where it may 

 be seen on the banks of the Canal, and has recently been 

 well exposed in the Railway cutting just beyond Midford 

 Station ; it occurs on Sion and Beacon hills, and near Charl- 

 combe. At Lyncombe and Beechen Cliff the rock, as 

 Moore states, is almost composed of Corals, Trigonia, Os- 

 trem, and Brachiopoda. 



„ , ^ Separating these beds from the Great Oolite 



Fuller's Earth. ^ ° 



above, comes a thick deposit of clay. It can be 

 traced all around our hills just below the top by the undulating 

 nature of the sloping ground, caused by the running down in 

 wet weather of the intervening clay, or the slipping over of 

 the solid beds above on the greasy unctious beds below. It 

 is yellow and blue in colour, and has generally near the 

 middle a bed of nodular earthy limestone, called " Fuller's- 

 earth Rock," but feebly developed in our neighbourhood. 

 -The total thickness around our hills is about 150 ft. Lately 

 important works have been opened on the south of the basin, 

 near Midford and Combe Hay, for the yellow earth, con- 

 sidered the most valiiable for economic purposes. It is im- 

 portant, too, as being a water-bearing bed around our hills, 

 throwing out from its surface the drainage of the Great Oolite 

 above, and forming the upper belt of springs in our district. 

 The characteristic fossils are — Ostrea acuminata, Waldeimia 

 ornithocephala, and Rhynconella varians, with several new 

 forms of Ostracoda, lately described by Professor Rupert 

 Jones and Mr. Sherborn in "Bath Nat^ Hist, and A. F. C. 

 Proc.^' vol. vi.,part 3,/. '249. 



The Great Oolite, for which Bath is so 



Great Oolite. . . . , 



famous, and hence often called " Bath 

 Oolite," caps all our hills, which are in some places, espe- 

 cially on the south, completely, honey-combed with old 



