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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Feb. 2Q, 



edges of strata of limestone, and a conformable mass of trap from 

 30 to 40 feet thick*. 



Present Sea-beach. 



A. Arenaceous Limestone. 



B. Limestone. 



B'. Hard Limestone (metamorphosed?). 



C. Trap from 30 to 40 feet thick. 



D. Sand vrith a few layers of stones. 



E. Eaised beach exposed. 



F. Raised beach concealed mider falling 



debris or grass. 



1. Reddish loam with angular and sub- 



angular stones. 4 feet. 



2. Concretionary layers of sandstone, 



2 feet. 



3. Layer of nearly pure sand, 1 foot. 



4. Conglomerate and breccia, consisting 



of rounded, subangular, and angu- 

 lar stones (with occasional flint 

 chips) imbedded in a hard ochre- 

 ous matrix, with sea-shells, and in 

 the upper part numerous bones. 

 The stones sometimes lie loose, but 

 in general are firmly fixed. Thick- 

 ness about 4 feet. 



7. Posttertiary Submergences. — A submergence of between 25 

 and 35 feet, snch as that indicated by the raised beach near Wes- 

 ton, would throw the plains or mud-flats near Weston, Clevedon, 

 Burnham, Bridgewater, &c. under a considerable depth of water. 

 During the time or times these flats were submerged, the caves 

 situated within reach of the waves woidd necessarily become more 

 or less rounded and smoothed, if not mainly excavated. Mr. Pooley, 

 F.G.S., of Weston-super-Mare, lately discovered a cave (now built 

 over) near the sea-level, at Southside, Weston, the sides of which 

 were corniced with smooth, parallel and horizontal grooves. Mr. 

 Pooley tells me that similar cornicings may be seen in the caves 

 near Loxton. The cave in the face of the cliff" near Uphill, described 

 by Mr. Day in the ' Geological Magazine,' exhibits smoothly rounded 

 and smoothly hollowed surfaces, with pot-shaped cavities. This, I 

 ascertained, was likewise the case with a small cave at a lower level 

 further south, which is partly filled with a loamy sand. The caves 



* The trap, I believe, has hitherto been regarded as intrusive. But a com- 

 prehensive inspection, will, I think, show that it is a bed which, in a fused state, 

 must have flowed over the limestone beneath, before the hmestone above was 

 deposited. Mr. Ravis, of Bristol, tells me there is a similar bed of trap in th« 

 limeijtone near Sandpoint, to the north of Weston. 



