COAL MEASURES BENEATH ESSEX. I4I 



of aU the borings in the London Basin (using the term in its wider 

 sense) in which Palaeozoic rocks have been reached. They are ten 

 in number, as follows : Culford (Suffolk), Ware, Cheshunt, Kentish 

 Town, Meux's Brewery (London), Crossness (Kent), Streatham 

 (Surrey), Harwich, Dover. Richmond. Not much new light after 

 all is thrown upon the question under consideration, since the 

 results of all these borings were generally known to geologists. A 

 gleam of light perhaps is gained from a consideration of the limited 

 distribution of the Jurassic strata under the London Basin. So 

 far as these borings can tell us anything, we can infer that (making 

 all allowance for a certain amount of denudation) the arm of the 

 Jurassic sea was co-incident with a line of synclinal flexure lying to 

 the north of the westward extension of the Ardennes axis through 

 the area of the Weald, as indicated in my article, and that in this 

 trough the coal measures of Dover had been let down, since it is 

 precisely along such a belt of country that the Jurassic strata are 

 found immediately overlying the Palaeozoic rocks at Richmond, 

 Streatham, New Oxford Street, and Dover. 



" As we advance northwards, however, we lose touch of the 

 Jurassic series altogether, and, so far as the borings can tell us, 

 enter upon a region of Palaeozoic strata, which in all probability was 

 a land-surface during the long period of time represented by the 

 Triassic and Jurassic formations. This is a simple inference from 

 the fact, that in the borings at Kentish Town, Cheshunt, Ware, 

 Harwich, and Culford, we pass at once from the Cretaceous strata 

 into those of the Palieozoic series. Earth-movements in this area, 

 about the beginning of the Cretaceous period, led to the submergence 

 of the land-area indicated above, so that the Cretaceous sea spread 

 over the whole of the south-east of England ; just as earth-move- 

 ments on a grander scale led to the submergence of the Bohemian 

 area, and the deposition of strata of Cretaceous age upon the older 

 Palaeozoic and Archaean rocks of that region. All this lends 

 emphasis to what was said in my article as to the significance of the 

 absence of Triassic and Jurassic rocks in all the East Anglian 

 borings. That the region of elevation in the East Anglian area 

 during Triassic and Jurassic time was of the nature of an axis 

 trending approximately to the north-east, is a hypothesis (as I before 

 pointed out) favoured by the penetration of crystalline rocks beneath 

 the Jurassic at Bletchley, and of the Carboniferous, at Northampton, 

 beneath the Trias. The paper just published contains information 

 which tends to strengthen that view, as ' further north, at Yarmouth, 

 Norwich, Holkham, and Lynn, such (Palaeozoic) rocks have not 

 been reached by borings taken to a deeper level than that at 

 Culford.' This would lead us to suppose that the axis of elevation 

 of the older rocks trends more to the east than was suggested in my 

 article above. 



" The few additional facts here indicated make the probability 

 of the existence of Coal-measures beneath north-western Essex 



