A HISTORY OF ESSEX 



fringe the marshes near Burnham. Again, in the western portion of 

 the county, near Loughton, on Buckhurst Hill and north of Chigwell, 

 there are gravels which it is exceedingly difficult to distinguish from 

 neighbouring gravels on a slightly lower level which seem to form part 

 of the true valley gravels. Some of these deposits may indeed represent 

 stages in the denudation of the country which followed the recession of 

 the ice-sheet. 



While the action of land-ice was partly to efface the old scenery by 

 thick accumulations of Drift, it tended also to degrade and soften the 

 bolder features ; but these to some extent have reappeared through the 

 influence of subsequent denudation. 



The passing away of icy conditions, the melting away of the land- 

 ice which enveloped so much of the ground, must have been attended 

 by the formation of torrential streams which initiated the present lines 

 of drainage. Along the Stour, Colne and Blackwater, and along the 

 Lea and Thames, we find evidence of later Pleistocene gravels and brick- 

 earths, to which attention must now be directed. Along the Crouch 

 however we find no such ancient deposits. Rising in the hills of Lang- 

 don and Billericay, it drains an area of London Clay comparatively free 

 from the Glacial gravels, which in other valleys afforded material ready- 

 made for the accumulations of valley gravel. The Crouch may indeed 

 have existed in Pleistocene times, and have simply eroded without depo- 

 siting much material along its course : but there is no evidence to show 

 that this was the case. 



VALLEY GRAVEL AND BRICKEARTH 



The deposits of valley gravel and brickearth are old accumulations 

 of the 'rivers and their tributaries, and they occupy grounds higher than 

 the Alluvium, but often extend beneath it. 



The more important tracts of valley gravel and brickearth are those 

 which occupy the Thames valley. They occur from Leyton and Strat- 

 ford to Barking, Romford and South Ockendon, in a belt which in 

 places is four or five miles broad, and rises 100 feet above the river. 

 These deposits belong to the earliest system of drainage along the pre- 

 sent valleys, and to a period when palaeolithic man co-existed with a 

 fauna many of the members of which are either extinct or no longer 

 inhabitants of this country. 



The mammalian remains have been met with in notable abundance 

 at Ilford and Grays, not because these were exceptionally favoured places 

 of entombment, but because the brickearth at Ilford and the Chalk below 

 the brickearth at Grays have been very extensively worked, and for many 

 years the remains were carefully looked after by the late Sir Antonio 

 Brady at Ilford and by Richard Meeson at Grays. 



Sir A. Brady observed that the bones near Ilford were mostly found 

 in the sands and gravels and in a very decayed condition, but they were 

 better preserved in the brickearth. The chief locality was the Uphall 



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