AND ASSOCIATED PERMIAN ROCKS OP DURHAM. 227 



ANALYSIS. 



Carbonate of lime 73*75 



magnesia 19 -53 



Sand, clay, oxide of iron 2-06 



Water, &c 4-66 



100-00 

 No. 50. Locality— BYERS' QUARRY, 



COAST, FOUR MILES N. OF SUNDERLAND. 



Lithological Characters. — Smoke-grey, compact, sub -crystal- 

 line, thin-bedded, surface planes irregular and thinly coated on 

 upper side with softer yellow limestone, which generally contains 

 numerous minute fossils {Entomostraca and Foraminiferd), and 

 broken or perfect specimens of shells (Axini and Ifyalini, §fc). 

 Fifteen feet thick, with one or two beds of highly crystalline and 

 concretionary limestone associated. 



ANALYSIS. 



Carbonate of lime 96 - 94 



magnesia 1-66 



Sand, clay, oxide of iron, &c 0-60 



Water, &c 0-80 



100-00 



This limestone was formerly worked and shipped to the Tyne 

 for economical purposes (for a flux in iron works, &c.) ; and 

 from its analysis, it would undoubtedly form a good tillage lime. 



No. 51. Locality— ROKER CLIFFS, 



SUNDERLAND. 



Lithological Characters. — Light yellow, soft, oolitic and vesi- 

 cular, thin-bedded; unfossiliferous. From the uppermost beds 

 of the Upper Limestone, which are nearly one hundred feet thick 



at this locality. 



ANALYSIS. 



Carbonate of lime 59 - 81 



magnesia 26-06 



Sand, clay, oxide of iron, &c 0-53 



Water, &c 13-60 



100-00 



