231 
IX. 
Notes on the London Clay and Bagshot Beds at “Oakhill 
Quarry,” Epping Forest. 
By N. F. Bobarts, F.G.S. 
[Read November 25th, 1882.] 
The section exposed of the upper beds of the London Clay 
and Lower Bagshot at “ Oakhill” Quarry and Brick-field on 
the south of the road running from Tlieydon Bois Railway 
Station to the “Wake Arms” public-house, and about one 
mile west of the station, has not, I believe, been yet described. 
Before dwelling upon the few details of this section which 
I have to bring forward, I propose to give a short general 
description of the main geological features of the country 
lying between Hainault Forest and Waltham Cross. In doing 
this I must disclaim making any attempt at originality, my 
only purpose being to arouse some interest in our local 
Geology, and to induce others to study it for themselves. 
The prevailing formation of both hills and valleys in this 
part of Essex is the London Clay, which has almost every¬ 
where been extensively denuded, and in consequence of its 
great thickness forms not only the hills and slopes, but also 
the bottoms of the valleys, although the Clay is sometimes 
covered up and hidden by recent gravels and alluvium. 
The valleys of the rivers Boding and Lea are good examples. 
Chigwell Bow stands about 170 feet above the Biver Boding, 
and is formed almost entirely of London Clay, which rises to 
a still greater height at the Wake Arms and High Beach, 
whilst the eastern slope of the Lea Valley is similar to both 
slopes of the Boding Valley. The thickness of the London 
Clay in places where the Bagshot Beds overlie it—showing 
that in these places no denudation of the Clay has taken 
place since the Bagshot Beds were deposited—is about 300 
to 400 feet. As a lule the upper beds of the Clay are wanting, 
