THE ESSEX FIELD CLUB.
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Chelmsford Club, stating his satisfaction at coming into personal relations
with the expert botanists of the Essex Field Club.
After adieux had been exchanged with the local contingent the char-a-
banc was "manned" at 7 o'clock, and after a long pleasant drive into
"the eye of the sunset," Stratford was regained just before 9 o'clock,
and so another delightful outing brought to an end.
FIELD MEETING AT HARLOW (614TH MEETING)
SATURDAY, 18TH SEPTEMBER, 1926.
A party of over forty members foregathered at Harlow station at
12.30 o'clock, some having travelled down by road, others (less fortunate)
having been victims of the usual inconveniences and delays which seem
the inevitable accompaniments of a slight mishap, however remote, on the
railway which "serves" our county.
The object of the meeting was a geological one, combined with visits
to various buildings of interest in the neighbourhood. Mr. S. W. Wool-
dridge, M.Sc., F.G.S., and the Hon. Secretary, acted as conductors.
A visit was first paid to a large pit to the east of the road leading to
Sawbridgeworth, where the section showed Chalky Boulder Clay of highly
calcareous nature, almost a chalk marl, full of chalk pebbles, and much
piped ; underlying the Boulder Clay, a series of current-bedded sands and
fine gravels exhibiting occasional minor faults, and with thin intercalated
seams of lignite. A number of derived Jurassic fossils occurs, and speci-
mens of Gryphaea incurva from the Lias, G. dilatata from the Oxford Clay,
and fragments of Belemnites, were found by various members of the
party. The erratic rocks found included small pebbles of Red Chalk from
the Norfolk coast, lignite of unknown provenance, a very few Bunter
quartzites, and a much decayed pebble of coarse whitish granite, whose
origin it is impossible to guess. Several good examples of marcasite
nodules occurred in the Boulder Clay, these evidently derived from a
not-distant Chalk outcrop. Many of the flint and chalk pebbles exhibited
minute black dendrites of oxide of manganese on their surfaces.
After lunch had been disposed of Mr. Wooldridge gave to the re-
assembled party a brief account of the geological features of the district ;
he visualised the enormous ice-sheet which in Glacial times covered
the face of the country and which he considered must have been 400 feet
in thickness : this ice came into our district from the north-west by way
of the Hitchin gap through the Chiltern Hills, and thence spread out over
the counties of Herts, Middlesex and Essex, as far south as the Thames
valley. Mr. Wooldridge emphasized the fact that the chief Essex river-
valleys were in existence before the arrival of the ice, which filled them up.
The Stort valley, for instance, in which the visitors stood, was known
by borings to be a deep pre-Glacial gorge buried beneath the Boulder
Clay and probably in part deepened by the erosion of the ice which over-
whelmed it.
From this fascinating demonstration of bygone climatic extremes
the party was hurried off to view the charming little Norman Chapel,
now desecrated for use as a granary, in the grounds of Harlowbury,