SUBTERRANEAN GEOLOGY OF SOUTH-EASTERN ENGLAND. 155
London and its environs, we might easily get Devonian rocks at Meux's
and at Turnford, and Triassic Beds in a synclinal basin between those
places at Kentish Town. And whether the Palaeozoic rocks form many
sharp folds or a few broader and gentler undulations, there is not
sufficient evidence to determine. But we have seen that in the
Department du Pas-de-Calais they maintain the much-contorted
character which they have in the neighbourhood of Namur. All of
economical importance that the deep borings in and near London
have established at present is the fact that it is useless to sink
through the Chalk with the view of tapping the water supplies of
the Lower Greensand. It is therefore extremely unlikely that many
borings for water will in future be made in the immediate neighbour-
hood of London having that object in view.
Additional borings between Kentish Town and Turnford might
do much to show whether any synclinal basin containing Coal-
measures exists between those places; and others north of Ware,
and between Ware and Harwich, might enable us to judge whether
any synclinal basin in which Coal-measures have been preserved exists
between the upper Silurian of the former and the lower Carboniferous
rocks of the latter place. But of course the true nature of this
Palaeozoic ridge may possibly only be ascertainable by means of
borings piercing through thicknesses of Palaeozoic strata so great as
to show whether we have in the London district a great simple
anticlinal ridge, or series of simple anticlinal and synclinal ridges, or
beds so influenced by immense lateral pressure from south to north
that they have been actually reversed, Coal-measures being found
below lower Carboniferous, and the latter below Devonian rocks, as
in the Pas-de-Calais.
If we suppose that no reversal of the Palaeozoic rocks has taken
place in the London district, and that at Turnford, Kentish Town,
Meux's, Richmond, and Crossness the bottom rocks are all Old Red
Sandstone or Devonian —Upper Silurian rising from beneath them
at Ware—then it is evident that there can be no coal-basin of im-
portance at, or due north of, London and south of Ware. And if
we adopt the opinion of Prof. Judd and Mr. Whitaker that at Kentish
Town, Richmond, and Crossness the bottom beds are Triassic, this
belief would tend but little to modify one's general view. For on
either hypothesis it would appear equally probable that Upper
Silurian rocks cropping out—below Cretaceous beds—at Ware, and
Devonians from Turnford to Meux's, Carboniferous rocks might be
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