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tertiiuy beds cut through by the Loudon, Chatliam, aucl Dover 

 ]{ailwuy at the New Road, Canterbury, and also describes a borin" 

 made by him at Stourmouth extending to a depth of 163 feet in- 

 cluding 20 feet of the underlying chalk. The fossils of the Thanet 

 sands, Mr. Whitaker states, are those indicative of a temperate 

 cliinale. They are principally bivalve shells such as the Cyprina, 

 Cythcrca, Pholadoraya, &c. At Pogwcll Bay the lower portion of 

 these sands are exposed to view, and at Reculvers the upper. At 

 both p'aros beds of sandstone occur. It has been remarked by the 

 same geologist tliat where the chalk has a thick covering of those 

 beds the sand-pipes are not so frc(}uent as wliere it is but slight. 

 Several sand pits have been opened in this and the next formation 

 known as the Woolwich bt'ds from which it is sometimes difficult to 

 distinguish it. The Thanet sands are however generally finer 

 grained and more evenly bedded than the "Woolwich. Pits occur 

 at St. Stephen's, Fordwich, and Boughton. The Woolwich beds 

 though sandy in this district, in others to the west, consist of 

 mottled clays, which caused it to be called the Plastic clay forma- 

 tion by the older geologists. The fossils are partly fresh-water and 

 partly marine ; the latter predominating towards the east, shows 

 that the direction of the river that deposited the fresh-water shells 

 must have been from west to east or in the same direction as the 

 Thames. (See Lyell's Elements, page 294.) It is supposed by 

 Prestwich that this river drained the Wealden area like the Med- 

 way, and so might have flowed in the direction indicated by the 

 fossils, through the lower and seaward portion of its channel. 

 Beds ot lignite and shingle also occur, but the most striking 

 accumulation of the latter is on the succeeding Old Haven beds. 

 These are rounded flint pebbles remarkably of the same size and 

 colour, their longer diameter being about an inch, and are evidentlv 

 the result of the waves of a stormy sea, which must have rolled 

 and re-rolled the large flints of the chalk until they were reduced 

 by these spherical pebbles and must have separated out, tlie large 

 from the small, on an evenly sloping beach, in a manner similar to 

 that in which shot is sorted in its manufticture by being allowed to 

 run down an inclined plane. The pebbles in some districts are re- 

 placed by ironstone notably between Selling and Boughton which 

 is also fossiliferous. There are masses of this ironstone at the Can- 

 terbury entrance to the Whitstable railway tunnel, and a curious 

 ferruginoiis conglomerate mentioned in a previous paper. An 

 attempt was made some years ago to work this ironstone, some 

 small mines having been at that time opened near 

 the " Sugar loaf " hill on the road leading from 

 Selling to Boughton, the object being to provido 

 ships with a remunerative return freight instead of 

 going back in ballast. The yield of iron was however not 

 great, only amounting in some specimens I analysed to 28 per 



