liv PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



western) borders of this somewhat semicircular indentation (open 

 apparently to the north) that the great coal-formation had its origin. 

 In other words, the Rhenish and Belgian coal-fields, together with 

 the midland and northern Coal-measures of England, are the remains 

 of a succession of fringing bands of dense vegetation occupying a 

 continuous tract of coast-line. At this period the central gneissic 

 plateau of France was a terrestrial area with lakes and rivers, and 

 supported a rich coal-producing vegetation, the remains of which are 

 preserved in the original depressions in which they were accumulated. 

 The author then pointed out other extensions of ancient land in va- 

 rious parts of Europe, and described the different physical conditions 

 with which they were connected. He showed that the Boulonnais 

 coal belonged to the Mountain Limestone series below the geological 

 horizon of the Franco-Belgian coal. This latter probably underlies 

 the oolitic rocks in the neighbourhood of the Marquise district. 



The author concluded his statement by deducing the following 

 inferences : — 1st. that the physical configuration of Western Europe 

 at the period of the upper or true Coal-measure period indicates the 

 probable continuity of a band of coal-growth from the midland and 

 south-west of England to the south of Belgium ; 2nd. that there 

 may also exist a lower stage of coal-deposits, extending somewhat 

 west of the Boulonnais and of equal value ; 3rd. that the influence 

 of the old axis of flexure on the distribution of the oolitic and 

 cretaceous groups, favours the presumption that there is no great 

 thickness of overlying strata interposed between the Coal-measure 

 series and the present surface; 4th. that the upper Coal-measures may 

 be regarded as occupying a line on the north of the Weald denudation, 

 or conforming generally to the direction of the Valley of the Thames, 

 whilst the lower series may occur on a line coincident with the chalk 

 escarpment of that denudation. 



However startling these views may at first sight appear to those 

 who expect to find all the intervening strata between the Carboniferous 

 and Cretaceous series, regularly deposited, it has nevertheless appeared 

 to many practical men as not at all exceeding the bounds of pro- 

 bability ; and when we recollect how many instances occur of different 

 strata being deficient in various localities, or so thinning out as not to 

 offer any practical difficulty to the solution of the question, the 

 apparent primd facie improbability is greatly diminished. More- 

 over, when we reflect on the vast practical results which would 

 accompany such a discovery as that of coal in the south-eastern 

 district of England, the truth of which might be tested by judicious 

 borings on a comparatively small scale, we can hardly refrain from 

 expressing a desire that such an experiment should be made. The 

 existence of granite masses stated to have been found in or below the 

 chalk formations of Kent, if indeed they are not transported boulders, 

 would appear to indicate that the crystalline basis of the stratified 

 rocks is, in some places at least, not at so great a distance from the 

 surface as might otherwise have been expected, had all the different 

 stratified formations been deposited in their normal or typical condi- 

 tion, and of the same thickness as they occur in other parts of 



