File:The Quarterly journal of the Geological Society of London (13889776637).jpg

BOULDEE- CLAYS OF LINCOLNSHIRE.
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(if not a cliff) of chalk at this place, and probably all along the line
of rise from the lower plain to the Wold hills.
At the same time it is clear that the Boulder-clay overrode
this cliff-line, and buried a considerable portion of the Wold land
to the westward. A thin outlier caps the high ridge between
Hawerby and Wold Newton, the summit of which is 382 feet above
datum-level ; and the same Boulder-clay occupies the valley-bottom
which runs northward from Wold Newton to E-avendale.
Fig. 2. — Plan of the country near Hatcliffe. (Scale 1 inch to a mile.
The ground occupied by Drift is indicated by diagonal shading.)
Kear East Eavendale there is direct continuity between the clay
in this valley and that outside the chalk ridge ; and the mapping
east of Hatcliffe (fig. 2) suggests the existence of a cliff-line breached
by the battering of ice before or during the deposition of the Boulder-
clay. From this locality the brown clays are traceable northward
by Laceby and Brocklesby to Barrow and Barton-on-Humber.
Westerly Extension. — From Hessle, on the north side of the
Humber, the so-called Hessle Clay sweeps westwards to North
Ferriby, and as it is also found on the south side of the river at
Barton and near South Ferriby, Mr. Searles Wood justly concluded
that it had once filled the great gap in the Wolds through which
the Humber flows. But if the Boulder-clay extended through this
gap, we should certainly expect to find it on the western side of the
Wolds, both north and south of the Humber, at similar low levels.
Mr. Searles Wood could not find it, and he suggests some elaborate
hypotheses to account for its supposed absence. These, however,
are fortunately rendered unnecessary by the simple fact that it is
not absent, but present in some force, both to the southward and
"westward of South Ferriby. It may be seen near Horkstow Bridge,