Mr. Rose's Sketch of the Geology of West Not folk. 1 77 



situation, by pointing out the parallelism of the vertical lines 

 of spathose matter in them and in the present cliff. It has not 

 been determined to what depth the breccia extends, but it has 

 been stated that the clay beneath is exposed at low water. 



At Dersingham the lower portion of the sand exposed is 

 colourless, nearly pure silica, sufficiently so for the use of the 

 glass manufacturer, and is shipped in large quantities for the 

 glass furnaces in the north. 



Between the castle and the water-mill at Castle Rising, I 

 observed large blocks of sandstone lying by the road-side, ap- 

 parently removed from the loose sand dug for domestic pur- 

 poses: they varied in colour from light ash to nearly a black. 



At Middleton, to the left of the road leading from East 

 Winch to Setch, a large quarry is worked for building-stone, 

 called the Blackborough Car-pit ; it is opened to the depth of 

 twenty feet, and the stone is highly ferruginous, overlying the 

 loose variegated sand which comes to the surface at the base 

 of the hill towards the west. At this locality the carstone is 

 intersected by innumerable veins of ironstone from one eighth 

 to an inch in thickness ; they run horizontally and vertically, 

 forming grotesque lines, all tending to a concentric arrange- 

 ment : the veins have a dark-brown surface ; the fracture is 

 granular, probably from an intermixture of sand, and has a 

 semi-metallic lustre. The carstone is very friable when first 

 raised, but hardens by exposure, and becomes an imperishable 

 building-stone. 



At West Bilney, carstone of a similar quality to the last 

 mentioned is quarried in a pit adjoining the garden of Bilney 

 Lodge. 



Section of the Pit. 



Vegetable soil and loam, varying from 2 to 4 feet. 



Rubble car 2 



Regular car of very loose texture 5 



Ironstone irregularly distributed, but hori-"l . . 



.11 /l to Z 111CS. 



zontally J 



Friable sand, upper portion ferruginous, lower""! 

 portion green, containing thin tabular car- | 

 stone and blocks of the same ; also geodes ^ 4t feet, 

 and hollow cylinders of ironstone filled with I 

 sand J 



Car with thin veins of ironstone containing! _. , 



a little clay J 



Hard carstone 6 feet. 



The hard carstone appears to be divided into layers, or 

 strata, varying in thickness from nine inches to thirty, some 

 separated by very thin layers of sandy clay, and other divi- 



Third Series. Vol. 7. No. S9. Sept.lSSS. 2 A 



