THE ESSEX FIELD CLUB.
145
in which were given many interesting topographical details, and a report was
also printed in the Proceedings of the Geologists' Association, Vol. X., p. 489.
The party arrived at Laindon about 3.30, and the objects of the meeting
being mainly geological, it was almost wholly under the expert guidance of Dr.
Salter, who had made a special survey of the district. The following report is
almost entirely his.
At the station he referred to the boring mentioned in the accounts of the last
excursion in 1888, when 342 feet of London Clay were passed through before
reaching the Lower London Tertiaries. The station is about 148 feet O.D.
At Mr. C, T. Johnson's brickyard, about 300 feet O.D., some redistributed
London Clay was seen, and a well pointed out, which had been dug for 27 feet
chiefly in London Clay. A good supply of water was obtained after passing a
bed of Septaria. The outcrop of the Bagshot sands being quite close, it is
probable that the occurrence of water in such a position is due to slipping,
similar to that seen later on at One Tree Hill. The Septaria, which had been
preserved by Mr. Johnson, yielded a good deal of teredo-bored wood. A small
stream near by issuing from a spring had formed a small well-marked valley.
Other springs along the junction of the Bagshot Sands and London Clay were
pointed out, and Dr. Thresh's Report on the water supply of this district
referred to.1
The party then proceeded to a section showing about 15 feet of Bagshot
Sands situated on the right of the road leading to Lee Chapel. The sands are
capped by one or two feet of hill-wash.
Dr. Salter stated that the sands were micaceous, and pointed to some clay
'bands on the west side, such as are characteristic of Bagshot deposits, and ate
well seen at Hampstead. He invited the members to search for fossils, as he
understood none had yet been found. Messrs. J. Francis and H. A. Rigg were
soon fortunate enough to find two casts of Lamellibranch shells hardened by
oxide of iron, and others of the party found more or less determinable fragments
of casts of shells. A detailed and prolonged examination of this pit would no
doubt lead to good results. This was the second occasion that members of the
Geologists' Association have detected fossils in the Bagshot Beds of Essex (cf.
Proc Geol. Ass., Vol. xi., p. 13. and Vol. xix., page 319.) The specimens were
very kindly handed to Mr. Cole for preservation in the Essex Museum.
At the top of the hill (385 feet O.D.), near the Crown, the tine view northward
was much appreciated, the hills about Brentwood, Billericay, Beggar Hill, and
Danbury pointed out, and the gravel formation on the higher parts referred to.
The party then proceeded to a small gravel section near the Crown. Dr. Salter
pointed out that the gravel was composed of Tertiary flint pebbles, subangular flints
and small angular and rounded pieces of Lower Greensand Chert, He regarded it
as the deposit of an old stream having connection with the Wealden area, and
that the hill on which they were standing owed its existence as such to the
strata below having been preserved by the gravel, while all around the strata not
so covered has been denuded away.
Another sandpit on the left of the road to Dry Street and Vange was then
visited. The clayey bands at the top were well shown, but no fossils were
found. The Director pointed out that the beds were lying flat, thus differing
from those seen in the next pit.
After walking about a mile, the road on the right to Stanford-le-Hope was
1 See Essex Water Supply, by J. C. Thresh, D.Sc., page 70.