326 Superficial Gravels and Clays. fjuly, 
neighbourhood of London interested in the matter can 
observe them for himself. 
The sections I have given, however, are all along an east 
and west line, with the surface of the ground a little over 
the 100-feet contour-line, and it will be well to describe the 
deposits at lower levels. 
At Ealing to the south of the line of railway, the nume- 
rous sections shown in the small gravel-pits, dug when 
houses were building, all showed the same divisions. At 
about 90 feet above the Ordnance datum-line the brick clay 
is very thin, and sometimes absent through denudation ; but 
below this line it again thickens. That it was originally 
present over the whole district is shown by the fadt that 
Railway-cutting, Ealing Station. 
s. Surface soil. _ a, 1. Unstratified brown clay. a, 2. Irregular patches of small 
pebbly gravel in clay. a, 3. Yellowish brown, rather sandy clay, a little strati- 
fied towards base. b. Sand passing downwards into sandy subangular gravel. 
patches of it are preserved all over the denuded areas in 
hollows or irregularities of the beds below. Thus in a long 
excavation that was made for a main sewer at Beaconsfield 
Villas, the trench ran north and south, and crossed two 
channels cut into the gravels. These channels were filled 
with the clay a, i. I have represented one of these filled-up 
channels in Fig. 13. The other was about 80 yards to the 
north, and was deeper than that figured. The filled-up 
channels ran east and west. 
South of this the gravels continue down the slope, and at 
about 70 feet above the Ordnance datum-line are covered 
continuously with the clay down to near the 50-feet contour- 
line. At Ealing Cemetery, which is just above the 50-feet 
line, the gravel occurs in patches only, in hollows in the 
surface of the London Clay, and the brick-clay is thin, 
though still present. Below the 50-feet line the surface 
dips more rapidly, and on the steeper part of the slope the 
