224 Mr. G. J. Hinde’s Notes on the 
wide opening underlaid by gravel. At the cross-roads at Foxley 
Hatch a pit was lately opened to a depth of 6 ft. in a coarse 
flint gravel, in which were several boulders of conglomerate 
similar to those already mentioned from Whiteleaf. ‘Two of 
these measured 30 x 24 x 17 in. and 23 x 17 x 12 im. respec- - 
tively. In all probability these have been brought down the 
Caterham valley, for none has been observed in the main valley 
south of the junction, whilst they are not uncommon lower 
down the valley nearer Croydon. 
We now come to the best known of the dry chalk valleys in 
our area,—that along which the main road and the railway to 
Merstham and Brighton are carried. It may properly be named 
the Hooley valley, from the village of this name situated in it. 
The head of this valley is a pass or gap. 439 ft. above O:D., at 
Harpsoak Cottage, a short distance north of Merstham in the 
Gault valley below, which is here at a level of 264 ft., or 175 ft. 
below the head of the Hooley valley. The summit of the chalk 
plateau on the east side of the gap is 624:ft. above O.D., and it- 
is here capped by clay-with-flints, containing, besides the usual - 
flints and pebbles, numerous pieces of iron sandstone, and-in 
some places, at slightly lower levels of 560-580 ft., many 
fragments of Lower Greensand chert. 
The only gravelly materials now exposed in the upper portions 
of the Hooley valley are those of the railway-cuttings between 
Hooley House (330 ft.) and the north end of the tunnel (413 ft.). 
A close examination of the beds is only practicable in a few 
places; they are from 5 to 15 ft. in thickness, and even more 
where pockets or pipes of gravel are let down into the chalk. 
The gravels rest on a very uneven surface of chalk, and appear 
to consist of a red clay containing the same flinty materials and 
fragments of iron sandstone, and, rarely, pieces of chert, as 
those in the clay-with-flints of the plateau above. In some of 
the pocket-like depressions there are lenticular beds of loam or 
sandy loam. 
The late Sir J. Prestwich * has referred to the ironstone and 
the chert in the gravel of this valley as a proof that the valley 
itself formerly extended more to the south, to the Lower Green- 
sand area, from which these materials have been derived, but: 
the occurrence of these same materials on the summit of the 
plateau directly bordering the valley shows that they must have 
been brought into our drainage area before this valley was 
formed, and that probably they have found their way into the 
gravels from the erosion of the plateau clay-with-flints, and not 
direct from the Lower Greensand rocks to the south. 
The length of the Hooley valley from the summit pass at 
* «Quart. Journ. Geol. Soe.,’ vol. xlvi., 1890, p. 171. 
