Proceedings. 43 



The next are the New Eed Sandstones, in three divisions 

 of alternate sands and marls, 1500 feet thick. The town of 

 Leicester lies on this formation. This is the lowest in the 

 series of secondary rocks. 



The next formation is the newest and uppermost of what 

 are called the Old or Primary' Eocks, and is called the 

 Permian system, a series of Magnesian Limestones, 800 feet 

 thick. Underneath this lies the Carboniferous formation, in 

 which alone, in England at all events, the true Coal-measures 

 are found. The distance from the top of the Chalk to the 

 Carboniferous formation is therefore 8,300 feet if all these 

 formations were found in their place, and of their full thick- 

 ness. Some have, however, never been deposited in this 

 part, or, if deposited, have been swept away. 



In May, 1855, Mr. Godwin Austen read a paper before the 

 Geological Society, in which, from a careful study of the 

 geological phenomena of Belgium, and the West of England, 

 he inferred that the axis of the Ardennes in Belgium was the 

 same as our Mendip Hills, and that these two out-cropping 

 parts of a long line of elevation of old rocks were connected 

 by an underground ridge of the same hidden by the mass of 

 overlying and unconformable secondary rocks ; he states that 

 the depression of the Thames Valley represents, and is 

 physically a continuation of, that which, extending from 

 Valenciennes, by Donai, Bethune, Theroanne, and thence to 

 Calais, includes the great Coal trough of these countries, and 

 he infers that at an early time a line of disturbed surface was 

 produced, having a general E. and W. direction, and which, 

 traversing a portion of the area of Coal growths, has placed 

 all the members of that series along its course either at or 

 near its present surface, and that we have strong reasons for 

 supposing that a band of Coal-measures coincides with, and 

 may some day be reached along, the valley of the Thames ; 

 while some of the deeper-seated Coal, as well as certain over- 

 lying and limited basins, may occur along and beneath some 

 of the longitudinal folds of the Wealden denudation. (This 

 hypothesis brings in the whole breadth of Mid- Surrey in this 

 locahty within its sweep.) This theory was afterwards con- 



