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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



coarse and occasionally pebbly iron-sandstone, in some places fossili- 

 ferous, at other places without fossils, and often closely resembling 

 in mineral character the ironstones on the Downs, it seemed at first 

 sight most natural to suppose those blocks might be remnants of 

 these beds mixed with the drift. 



It might also be a question whether the loamy sands and ironstone 

 were not portions of the Lower Tertiaries in situ, but modified in 

 structure and character in consequence of their being nearer the 

 shore of the Old Tertiary sea than the main mass between Faversham 

 and Canterbury. But against this view I found that in all the out- 

 liers of Lower Tertiary strata, dotted at intervals over the North 

 Downs even to the very edge of the escarpment, the sands and asso- 

 ciated beds retain their clear, undisturbed, more uniform and fresh 

 appearance, and general lighter colour, exhibiting in these isolated 

 masses an exact counterpart in their structure and aspect to the same 

 beds in the central Tertiary mass of the Thames Valley*. I further 

 found that the loamy sands and ironstones formerl outliers, often 

 lower, or on a level with those of the Lower Tertiary strata, between 

 which they seem to run as shown in the following section : — 



Fig. 1. — General Section from the Valley of the Medway to the 

 Valley of the Darent, parallel with and near to the edge of the 

 Chalk Escarpment. 



Shoreham. 



Lower Hailing. 



a—f Loamy yellow sands, i, Lower Tertiary sands and pebble-beds, m, Chalk. 



Above Otford and at Vigo Hillf, the beds consist of fine argillaceous 

 buff-yellow sand. There is a much better exhibition of them at the 

 hamlet of Paddlesworth, about four miles W.N.W. from Folkestone, on 

 the very summit of the Chalk Downs, and at a height of probably about 

 600 feet above the sea. They there form a slightly detached hill, and 

 consist of 30 to 40 feet of ochreous and ferruginous sands,more or 

 less argillaceous, with subordinate fine quartzose grits and broken 

 beds and seams of iron-sandstone, — some of these forming blocks of 

 3 to 4 feet wide by 1 foot thick, or even more. These blocks, which 

 are common in and about the hamlet, sometimes contain flint-pebbles 

 and unrolled flints. The fields in the neighbourhood are strewed 

 over with fragments of ironstone, and in a few of these I found 

 on one occasion some pieces of fossil wood pierced by the Teredo, 

 together with that which appeared to be the cast of a bivalve shell. 

 Yet on the neighbouring shore at Folkestone, which is covered at 



* The Tertiary sands also never present in Kent or Surrey the variable coarse 

 quartzose grits and loamy sands prevailing in the Vigo and Folkestone-hill beds ; 

 whilst the flints found in the former are always much more worn. 



f Ten years since, a good section of these sands was exposed here, but on a 

 recent visit I found only one small opening preserved in a sand-pipe on the side 

 of the lane descending the escarpment. 



