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 Hssex, 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 Hast 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 
