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Should the Somersetshire coalfield be repeated to the east, 
which is by no means improbable, we should then expect to find 
that extension under the great plain of Salisbury and the Kennet 
Valley, by Hungerford and Newbury, thus meeting the Belgian 
prolongation from the east 25 miles due north of Marlborough. 
The Burford trial has proved an extension of either the Forest 
of Dean or the Bristol coalfield, or both, at (as before stated) 
1,184 feet in depth ; and it is 35 miles east of the two coalfields 
named, and thus much nearer the areas predicted by Mr. Godwin- 
Austen. 
Professor Prestwich, in evidence before the Royal Commis- 
sion,* favoured the view of this easterly extension from the 
present boundary of the Bristol coalfield, and knew no reason 
why a coalfield may not be entirely covered up east of Bath, 
or Radstock, &c. Again we refer to the Burford boring as tending 
to confirm Professor Prestwich’s views. 
The axis of Artois, which plays so important a part in the 
physical structure of the region through which it passes is 
traceable from the Mendip Hills to the old county of Artois 
in France; and the singular unconformable relation of the 
Oolitic beds of Frome, &c., to the Carboniferous masses of the 
Mendip and its anticlinal, are the same as those of the Oolites 
of the Boulonnais. We now partly know what thickness the 
Jurassic rocks attain below the Wealden beds, in the Wealden 
area, where 1,990 feet have been passed through, 800 of which 
were Portland, Kimmeridge, and Oxford clay. So that the 
mooted point in Mr. Austen’s paper ( loc . cit.), to what extent 
the Oolitic group may exist below the Wealden and Cretaceous 
groups of Kent, Sussex, and Surrey, has been partly set at rest, 
but not decided either as to complete sequence, presence, or 
thickness, for nothing below the Oxford clay is yet known, and 
therefore the Palaeozoic rocks or their age can only be inferred. 
Sub-Wealden Area and its Exploration. 
In April 1872, at the meeting of the British Association at 
Brighton, it was arranged that a trial should be made in the 
Wealden area, for the purpose of testing the presence of and 
depth to the Palaeozoic rocks beneath the secondary strata of 
the Wealden. This undertaking had a twofold bearing ; the 
first being, as before stated, to test the thickness of the over- 
lying secondary rocks, and the age of those older series that 
may be beneath them. The second had special reference to the 
solution of the problem propounded by Mr. R. Godwin-Austen, 
relative to the existence and extension of the coal measures or 
* Report of the Commissioners appointed to inquire into the several matters 
relating to coal in the United Kingdom. Minutes of Evidence, pp. 146-418. 
