File:The Quarterly journal of the Geological Society of London (13365159755).jpg

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PROCEEDINGS OF THE GEOLOGICAL SOCIETY. .DcC. 5,
Section of Railway Cutting at Brentford.
1. Vegetable mould ; 1 foot.
2. Brickearth, a fine bro'RTiish loam ; 4 feet.
3. Fine sand, mostly stratified and obliquely la-
minated, with occasional wavy and irregular
veins of small gravel ; 6 feet.
4. Sand, with light- coloured clay and irregular
gravel, containing bones ; 6 to 8 inches.
5. Ferruginous gravel and sand, with patches of
clay ; 1 foot.
6. Clayey sand and sandy gravel, with occasional
large flintstones, partly ferruginous at the
upper part, containing bones and shells; 1
to 2 feet.
7. Ferruginous sand and gravel ; about 6 inches.
8. Light clayey sand and ferruginous gravel, with
boulders of quartz, granite, rock with am-
monites, &c., also bones, &c. of ox, deer,
&c. ; 6 to 7 feet.
London clay.
third of a mile, and presented great variations in the order and rela-
tive thickness of the sands and gravel, which pass into one another
in a very irregular manner.
No remains were, I believe, found in the brick earth and sand
(2 and 3) ; the sand (3) throughout its whole extent was stratified
and obliquely laminated, some of the layers being more ferruginous
than the others, and occasionally interstratified with veins of small
gravel ; the ferruginous gravel (5) is of less regular thickness, the
upper surface being sometimes eroded and the hollows subsequently
filled with a coarse greyish sand and light clay (4), containing bones ;
the clayey sand (6), also containing bones, is the chief depositary of
the shells, which were generally in a perfect state of preservation, the
Anodons retaining their usual brown epidermal covering.
The chief mass of the ferruginous gravel (7) consisted of rounded
and angular chalk-flints of various sizes ; but occasionally intermixed
with them were a few pebbles and small boulders of other rocks, as
London clay septaria with Teredince, indurated greensand, sand rock
with ammonites, fragments of pyritical ammonites (Oxford clay?),
coarse reddish sandstone, white quartz, granite, &c.
The bones, although occurring in all the layers below No. 3, were
most abundant in the lowest stratum ; on one side of the railway, a
vein of sand, containing shells, was observed, intercalated with this
gravel bed. Below the gravel bed is the London clay upon which
the whole deposit rests, but the depth of the clay was variable and