Ixxxii PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [Juiie I912,. 



It will be most convenient to treat these questions in pairs, 

 taking the first pair together, and following that up with a 

 consideration of the second pair. 



(h) Buried and Detached Coalfields. 



We may approach the first two questions on a pinori grounds. 

 There can be no doubt that the existing coal-basins are but the 

 relics of a once widely extended area of practically continuous 

 coal formation. This covered the greater part of England and 

 considerable areas in AYales, Scotland, Ireland, and the neigh- 

 bouring Continental countries. Some parts of the other countries 

 were certainly so situated that, whatever other deposits were or 

 were not forming there, the conditions were not suitable for the 

 growth of coal. But in England, when we except Devon and the 

 extreme south of the country, with some parts of the Midlands 

 and possibly the Lalte District, there is no direct evidence that 

 any large tract lay outside the area of deposition of workable coal. 

 The occurrence of coal in the Pas de Calais and in the Eranco- 

 Belgian Eields seems to indicate that the area favourable for coal 

 formation was very extensive. There is, then, the probability that 

 under the cloak of Neozoic rocks a number of Coal-measure synclines 

 may be preserved, corresponding to those known and worked 

 where the Palaeozoic outcrop has not been hidden beneath newer 

 rocks, and, if so, that thej may bear supplies of workable coal. 

 The extension of the worked coal-basins under the cover was part 

 of the result which was confidently anticipated from the application 

 of this course of reasoning. A further consequence is the likelihood 

 of a similar occurrence of other basins, not necessarily connected 

 with those at present known to us, but isolated from the known* 

 coal-basins and perhaps from each other. Godwin-Austen's pre- 

 diction of the occurrence of Coal-measures in South-Eastern 

 England was founded on his grasp of the consequences flowing from 

 a particular type of underground structure, and the verification 

 of his prediction by the discovery of coal at Dover and elsewhere 

 is a triumphant vindication of this class of reasoning. At the- 

 same time, it gives some sujDport to the expectation of other 

 concealed and isolated coalfields, and this expectation appears 

 to be justified by the results of borings in other parts of the 

 country. 



N'cw, the collective extent of England and Wales (roughly 58,000 

 square miles) is divided geologically into two portions. The line 

 dividing the two parts is approximately that which may be drawn 



