GEOLOGY locality of the royal residence. These sands, according to Mr. Lamplugh, may possibly be of an estuarine character ; they are current-bedded, and they contain fragmentary plant-remains and pyritous nodules with wood. They occur at Downham Market, and may be seen in pits on Grimston Common, on Sandringham Warren, and in the railway-cutting at Wolferton. The overlying clayey beds, termed by Mr. Lamplugh the Snettisham Beds, have been worked for brick-making at Dersingham, Snettisham and Heacham. They form a belt of moist ground, the clays throwing out springs from the overlying sandy division. Northward from Heacham the Snettisham Beds have been traced to the foreshore beneath the Carstone at Hunstanton, where the clays seen at low tide were formerly thought to be Kimeridge Clay. South of Dersingham this clayey division thins out, and its place is taken by an irregular band of gritty ironstone containing obscure casts of marine fossils. This ironstone, or ragstone, caps the Sandringham Sands on Sandringham Warren and for some distance southwards. The division is regarded by Mr. Lamplugh as a marine clav which was formed somewhat rapidly. Among the fossils, which occur in nodules of iron- stone and clay-stone, are Pecten cinctus, P. orbicularis, and species of Cardium, Pleuromya, Trigonia, Crioceras and Belemnites, which suggest correlation with the Tealby Limestone of Lincolnshire. Leaves of plants also occur. Above this clayey division, or its equivalent ironstone, is the Carstone. It is the chief building-stone of Norfolk : a brown friable rock known as ' Gingerbread Stone,' which is largely quarried and hewn into shape at Snettisham, and was formerly worked at Middleton and other places. Small pebbles of lydite or chert are conspicuous in the rock at Hunstanton, and stone of this character was in old times fashioned into querns. At Hunstanton, there are found in the base of the division phosphatic nodules and also concretionary masses of hard grit yielding Ammonites deshayesi, Perna mulleti, and other fossils suggestive of the Atherfield Clay of southern counties. Black phosphatic nodules and fossils have also been found between the top of the formation and the base of the Gault at West Dereham, where formerly they were dug. The fossils resemble those of the base of the Folkestone Gault. In mass the Carstone may represent the Hythe, Sandgate, and Folkestone Beds of the south-east of England.' It was probably deposited in a somewhat deeper sea than the Snettisham Beds, as indicated by its wide extent and uniformity. The Lower Greensand where exposed at the surface forms dry heathy commons and warrens, with occasional tracts of woodland, and the land rises to about 120 feet. The soil is deep and sandy, and sometimes crimson or purplish in colour. That of the lower sands can hardly be called fertile, but a better soil is furnished by the Carstone. It is a water-bearing formation, but it has yielded several ferruginous or chalybeate springs, one of which, formerly of local repute, occurs at Gaywood, near Lynn. Ochre has been worked at this locality, and
- G. W. Lamplugh, notes in Geology of the Borden of the Waih, pp. 16-25.
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