and on the Drift of the Eastern Counties. 195 



a close survey of the area would afford the means of testing how 

 far their horizons accord; the grouping, however, of the Drift 

 sands and gravels which, as I have to show in the case of Suffolk 

 and Essex, succeeded the Red Crag, goes to prove that there was 

 a gradual and continuous recession of the coast-line during the 

 period succeeding the Red Crag ; so that, by the incoming of the 

 great northern Clay Drift, that coast had reached the western 

 side of those counties. This and other circumstances not within 

 the compass of this paper lead me to a belief that some of the 

 deposits of the north-east of Norfolk belong to an horizon at 

 least as old as the lowest beach stage of the Red Crag. The 

 view that I take of the direction of the coast-line prevailing 

 during the Red-Crag period is indicated by the easternmost 

 dotted line on the small map annexed to this paper. 



The formation into which the Chillesford beds pass, and 

 which overlies in common those beds, the fifth stage, and the 

 beach stages of Red Crag, is one occupying a large area; and in 

 that respect, and in the thickness of its beds, it occupies a far 

 more important position than do any of the beds I have been 

 discussing. From its distinct character, both in the material 

 composing it and in the limited and definitely marked spread of 

 the deposit, as well as in the entirely different geographical 

 conditions under which it was formed, it appears desirable to 

 distinguish this deposit from the great overlying Clay drift 

 which has already received the designation of the Boulder or 

 Northern Clay Drift. I propose therefore to call it the Lower 

 Drift of the Eastern Counties. This formation is composed, 

 over the Red-Crag district, almost exclusively of sands which at 

 the bottom are loamy and rich and highly ferruginous, but 

 gradually become more siliceous in their upper parts. Although 

 where the valleys cut through the deposit down to its lower beds 

 and the Red Crag rich lands occur, yet the upper or siliceous 

 beds exposed as tablelands over large tracts form the barren 

 heaths or sheep-walks of Eastern Suffolk. These beds distinctly 

 pass under the Boulder-clay wherever the denudation has not 

 removed the latter : every river-valley of East Suffolk and 

 North-east Essex affords the means of testing this, as the whole 

 of the more seaward extremities of these valleys have been cut 

 through this formation, leaving the upper or Clay Drift as 

 cappings on the higher grounds, the mixed soils of these coun- 

 ties being formed by the overlying clays where denuded down 

 to a crust thin enough to mix with the underlying sands. 

 These sands gradually change to gravels as the formation extends 

 southwards, while they, after passing under the Clay or upper 

 Drift, reappear on the western sides of Suffolk and Norfolk, 

 forming the very extensive sand-tracts around Brandon. There 



