176 Mr. Rose's Sketch of the Geology of West Norfolk. 



rious magnitudes, and ferruginous matter cemented into beds 

 of sandstone through the agency of aqueous infiltration, and 

 separated from inferior beds of similar character by a consi- 

 derable mass of loose white sand. In the lower beds exposed 

 at Hunstanton Cliff many of the quartzose pebbles are suffi- 

 ciently large to give the rock the character of a breccia. 

 The loose beds occasionally inclose thin strata of fullers' 

 earth and a tenacious green clay* : its upper portion is inva- 

 riably ferruginous, occurring in thin layers of hard sandstone, 

 or tabular masses containing numerous veins of ironstone. 



Extensive portions of the surface of these sands are ex- 

 tremely sterile, as at Dersingham Heath, Castle Rising, 

 Bawsey, Ashwicken, Blackborough in Middleton, and Should- 

 ham Warren. 



In all parts of the sandstone range occur springs of water 

 with a chalybeate impregnation, but the fame of their medi- 

 cinal virtues has not extended beyond their immediate vici- 

 nity. I cursorily examined the water of Gaywood near Lynn, 

 and ascertained that it resembled the Tunbridge, but did not 

 retain so much free carbonic acid. 



The dip of these beds is about five yards in the mile ; and 

 I consider their entire thickness to be about eighty feet : their 

 surface width averages nearly three miles. 



For a building-material the carstone is invaluable; the noble 

 stables at Houghton Hall are built of it : " our ancestors 

 formed it into querns or corn-millsf." 



As these sands exhibit peculiarities at different localities, 

 I will notice a few that I have met with, beginning with Hun- 

 stanton. In the cliff is exposed a section of this formation 

 between forty and fifty feet in depth : the upper two feet re- 

 semble the consolidated carstone usually found above the 

 more friable and light-coloured bed, which at this spot im- 

 mediately succeeds it to the depth of eight feet, and has a 

 greenish shade of colour ; then follows a breccia, more than 

 thirty feet in thickness, horizontally and vertically divided 

 into tabular masses of considerable magnitude by a loosely 

 aggregated sand : numerous veins of white spathose matter 

 not thicker than wafer-paper run vertically through the breccia 

 at irregular distances from each other. Great numbers of 

 blocks of the breccia are seen upon the beach occupying their 

 original site, the more friable materials of the cliff having 

 been removed by the waves of the ocean. On my visit to the 

 cliff last summer, Mr. Edward Muggridge, of Lynn, satisfac- 

 torily proved to me that these masses retained their original 



* The colouring ingredient is silicate of iron. 

 t Geology of Norfolk, p. 30. 



