1825.] Mr. Webster's Tleply to Dr. Fitton. 43 



I shall begin by stating, that a bed of ferruginous sand 

 appears at Hunstanton, in Norfolk ; and passing under the 

 marshes of Ely, reappears in Huntingdonshire; is seen in Bed- 

 fordshire under the name of the Woburn and Leighton Beau- 

 desert sands, and extends into Oxfordshire. This bed has been 

 called by all English geologists, to the present day, the ferrugi- 

 nous sand; and is so represented in all the geological maps. It 

 is the third in succession below the chalk, being separated from 

 it by one of firestone (the green sand of Smith), and another 

 of blue clay or marl. 



In the wealds of Kent and Surrey, a bed extends from Folk- 

 stone through Coxheath, Leith Hill, Nutfield, Wolmer Forest, 

 Hindhead, &c. but sinks below the sea at Beachy Head. In 

 the greater part of its course, this bed is highly ferruginous ; 

 but in some places, and remarkably from Folkstone to Maid- 

 stone, it has in it beds and nodules of hard limestone with dark 

 green and ferruginous grains. The fossils are much fewer, and 

 do not appear to be the same as those in the bed above it 

 which I have called green sand. 



In the Isle of Wight, also, a bed of highly ferruginous sand 

 lies in the same situation with respect to the chalk, at Red 

 Cliff in Sandown Bay ; and it may be traced along the 

 south side of the island by Shanklin, Dunnose, Blackgang, 

 Atherfield, and Compton; and also over a great part of the inte- 

 rior of the island. This sand, which varies much in its character, 

 contains in many parts abundance of granular hematitic iron 

 ore, and sometimes green earth. It also has, in some places, 

 though not generally, nodulesof limestone with fossils and green 

 particles which resemble the rock of Folkstone. 



Although the Car stone and Woburn sands have been 

 regarded by Mr. Conybeare as identical with the Hastings beds, 

 and not with the Nutlield range, yet he has not favoured us with 

 his reasons for this opinion ; and no sections have been published 

 that prove it. On the contrary, when we examine the succes- 

 sion of beds as described by Mr. Smith and others on the west 

 of the chalk in England, we find that it resembles exactly the 

 structure of Kent and Surrey, the succession being green sand, 

 blue mail, ferruginous sand. 1 may add, that on examining 

 hand specimens from the bed below the gault in Cambridge, they 

 appear to me to resemble exactly those from Red Chff'^ Isle of 

 Wight, which'is allov.xd by Dr. Fitton to be the same as the 

 Nutfield range. 



In all the above-mentioned places, this bed is separated from 

 the last (the green sand of Smith and Townsend) by one of blue 

 day or n.arl, which in Cambridgeshire is called gault, at Folk- 

 s'.one the Folkstone blue marl, and in the Isle of Wight, by 

 myself, the blue marl. This bed is generally characterised by 

 peculiar fossils, although these are very unequally distributed. 



