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terminating* westwards of Ware against the Silurian series, the 
physical geography aspect of which at the time of the coal 
growth must have been much the same as the present, could the 
80 miles area be re-elevated from 800 to 1,000 feet. 
Another boring is being carried down by the New River Com- 
pany at Turnford or Wormley, six miles south of Ware, the reve- 
lations from which are more than anxiously looked for. This 
piece of engineering skill it is intended to complete as far as 
passing through the Lower Greensand. The Turnford boring is 
now 980 feet deep, and still in the Gault ; it is therefore 200 
feet lower than the bottom of the Ware rocks. This increased 
depth is owing to a depression, or perhaps valley, in the Paleo- 
zoic land below, which seems more than probable, when we know 
that the same thickness of Gault occurs over the northern area 
generally. It is 160 feet thick at Ware, Turnford, Loughton, 
Kentish Town, and Tottenham Court Road ; at Crossness, 140 feet. 
In most cases, when bored through, this Gault has a floor composed 
of Palaeozoic rocks ; at Kentish Town a red micaceous sandstone ; 
at Tottenham Court Road the Lower Greensand rests upon a true 
Upper Devonian ; at Ware on the Wenlock rocks of the Upper 
Silurian, and at Crossness on red sandstone (age ?). We are 
thus justified in stating that the space between Messrs. Meux’s, 
at Tottenham Court Road, and Ware — a distance of 24 miles— 
is occupied by the Upper Silurian, and probably the Lower, 
Middle, and Upper Devonian rocks, which may be rolled and 
folded on their dip. To what distance rocks of older date 
may occur north of Ware, further experiment only will decide. 
Harwich — which lies ten miles further north, and probably on 
the strike — has revealed them at a depth of over 1,000 feet. 
Few, perhaps, are aware of the difference that exists in the 
thickness of rocks of the same age in different, yet not very 
remote localities. In Britain the Cambrian and Lower Silurian 
deposits are from 20,000 to 30,000 feet in thickness ; whilst in 
Sweden and Russia the deposits which are the equivalents and 
representatives of these epochs rarely, if ever, exceed 1,000 
feet. This difference is due to the form and nature of the pre- 
Cambrian land on which the newer series, Cambrian and Silurian, 
are placed ; for there cannot be any doubt that such pre-Cam- 
brian land did exist, and extended over the present known Euro- 
pean area, with probably a great expansion westwards of the 
British Islands and the Spanish coast. The old plateau before- 
named is part of this extension. I believe also that the crystal- 
line rocks of Scandinavia to the north constituted a part of this 
pre-Cambrian stage, and also parts of North Wales, and the north- 
west of Ireland. The Hebrides and St. David’s are remnants of 
this epoch of the highest antiquity. This old land must have 
been slowly submerged and denuded to receive the so-called 
