344 Mr. Parkinson on the Strata^ 



also frequently turned up with the plough in that neighbourhood. 

 They. have likewise been found at Dartford, at Bexley, and at Brom- 

 ley, to the southward. 



Mr. Thorpe also relates that in the parish of Stone, there was a large 

 mass of stone, of some hundreds weight, full of shells, which was 

 brought from a field, and used as a bridge or stepway over a drain 

 in the f\rm-yard. (Custumak Roffense^ p. 255.) 



In several spots in the neighbourhood of Bromley, stone is found 

 near the surface, formed of oyster-shells, still adhering to the pebbles 

 to which they were attached, and which are similar to those which 

 have been just described, as occurring at Plumstead and at Charlton : 

 the whole being formed by a calcareous cement into a coarse shelly 

 limestone containing numerous pebbles. The only quarry of this 

 stone wliich has been yet worked is in the grounds of Claude Scott, 

 Esq. The opening hitherto made is but small ; it is however suffi- 

 cient to shew that the stratum here worked has suffered some degree 

 of displacement, as it dips with an angle of about forty-five degrees. 



At Feversham, over the chalk, Mr. Francis Crow has discovered 

 a bed of dark brown sand, slightly agglutinated by a siliceous cement, 

 and intermixed with a small portion of clay. In this stratum, which 

 has been hitherto but little explored, he has found in a siliceous 

 state, specimens of Strombus pes pelicani and a species of Cucullaa^ 

 nearly resembling those which are met with in the Black-down whet- 

 stone pits. 



Patches of plastic clay are frequently found over the chalk : some of 

 these are yellow, and employed for the common sorts of pottery ; but 

 others are white, or greyish white, and are used for finer purposes. 

 The coarser clay is very frequently met with, nor are the finer kinds 

 of very rare occurrence. In the Isle of Wight two species of plastic 

 white clay are worked for the purpose of making tobacco-pipes. 



