AND ASSOCIATED PERMIAN BOCKS OF DURHAM. 223 



concretions and the marl, or the hard and soft portions, are ana- 

 lysed separately. 



ANALYSIS. 



38. 39. 



SOFT PART. HARD CONCRETIONS. 



Carbonate of lime 62-94 89' 10 



magnesia 33-73 8-74 



Sand, clay, oxide of iron, &c. . . 1-93 1-53 



Water, &c 1-40 0-63 



100-00 100-00 



No. 40. Locality— FULWELL QUARRY. 



(MARL OF " DUN STONE.") 



Litliological Characters. — Light yellow, very soft and friable — 

 falling to powder on exposure to the weather, with greyish con- 

 cretions and druses of calc spar ; unfossiliferous. 



ANALYSIS. 



Carbonate of lime 54-89 



magnesia 39-85 



Sand, clay, oxide of iron, &c 2-66 



Water, &c . . 2-60 



100-00 



No. 41. Locality— FUL WELL QUARRY. 



CONCRETIONS IN MARL OF " DUN STONE." 



Litliological Characters. — Greyish yellow, crystalline, with a 

 sharp flinty fracture, and druses of calc spar. 



ANALYSIS. 



Carbonate of lime 80-01 



magnesia . . . . , 9-93 



Sand, clay, oxide of iron, &c 2-06 



Water, &c 800 



100-00 

 No. 42. Locality— FULWELL QUARRY, 



GREAT MARL BED, TOP. 



Litliological Characters. — Light yellow, very soft and friable, 

 falling to powder on exposure to the atmosphere, with irregular 



