266 A Geological Description of the Parish of Portishcad, 



being soft, a specimen of their junction is not readily to be removed. In 

 this bay the hjematite crops out in a large vein. 



The pebbles at the eastern end of the bay are sandstone, old and new j 

 a few quartzose and others washed out of the dolomite, and a very few 

 of lias. At the point forming the western extremity of the bay, the new 

 red forms the cliff; and, vvitii the occasional reappearance of the pennant, 

 continues to form both cliff and beach nearly to the battery. 



The new red, or rather the dolomite, for they pass imperceptibly into 

 each other, is here of a light buff colour, in some places so friable as to be 

 scraped for sand, and in others sufficiently compact to form a very excellent 

 building stone. It contains very few fossils ; three connected joints of an 

 encrinite were the only result of a whole day's research. 



A measurement of the face of the cliff, a little to the east of the bath house, 

 gives six feet of supersoil, three of buff-coloured sandstone, six of marly 

 beds, and twenty of yellow sandy dolomite, reposing on the basset edges of the 

 pennant. In some parts a deep red bed comes into view, being the lowest 

 here deposited. The platform upon which the battery has been thrown up 

 is formed of new red sandstone, connected with that just described; it 

 overlies beds of carboniferous limestone, dipping at about 70° N. by E. but 

 in parts singularly contorted. 



In external character these beds more nearly resemble red dolomitic 

 paste, than the regular carboniferous limestone, but they contain vast 

 quantities of crinoidea and producti ; and of the former, the stems of the 

 cyathocrinites are remarkably well seen. 



The inclined beds cease abruptly, and the beach is formed for some 

 distance westward by beds exactly similar, but disposed horizontally 

 or nearly so, with occasional abrupt undulations. They there terminate 

 suddenly in a high shingle bank of old red pebbles, defending a small 

 triangle of alluvial flat from the sea, and continuing topped by the em- 

 bankment for a new rood, until, towards the middle of VVoodhill Bay, the 

 old red appears in situ, dipping 20°, at about S. E. 



The old red continues to appear throughout the north-western part of 

 the district, as the fundamental rock. It forms the cliff at Blacknore 

 point, in which a series of marl beds, twenty feet in thickness, are seen ; 

 and above them a bed of quartz conglomerate, which passes off above by 

 degrees into the regular honogeneous old red. This is an excellent place 

 for specimens of the old red and its conglomerate. 



Further on, the old red forms only the basis of the cliff and the greater 

 part of the beach ; the former being caj)ped by dolomitic conglomerate, 

 blocks of which, some of them apparently in situ, lie scattered along the 

 shore. The pebbles of this conglomerate are generally derived in the 

 greatest proportion from the subjacent rock, and here it is full of quartz 

 and old red pebbles. The cementing paste is white and dense, though 

 abounding in cavities : it presents a very few broken crinoidal stems. 



