46 Proceedings. 



and of the North of France ; what evidence we have therefore 

 seems to lead us to two conclusions, /. e., that Coal-measures 

 are likely to occur somewhere along the line of the Thames 

 Valley, or in neighbouring tracts, and that these Coal-mea- 

 sures are likely to yield workable Coal. It is rash to attempt 

 to foretell the future, but it seems to me that the day will 

 come when Coal will be worked in the South-east of 

 England." 



Nearly all the leading geologists are now of opinion that 

 the line of Coal-measures will be found along the North 

 Downs, and that they will be found in detached fields from 

 five to eight miles in width somewhere a few miles south of 

 London, it being found that underneath London rocks older 

 than the Coal-measures are found immediately under the 

 Secondary Eocks, the Coal-measures being missing ; while on 

 the other hand, the lower Secondary Rocks have a tendency to 

 thicken south of the North Downs, as in the boring at 

 Netherfield, where they began in the lowest beds of the 

 Wealden formation, and ended 2000 feet in depth in the 

 Oxford Clay. I may say that I have offered a site for boring 

 on the North Downs, about two miles east of Caterham. 

 Professor Whitaker appears to think that a likely spot, but 

 suggests that a site a few hundred yards more to the north, 

 on the same estate, would be better, as the Secondary Rocks 

 would be thinner, and the Coal, if found, would probably be 

 nearer to the surface. 



As to the condition of the Coal-measures when found, 

 Professor Prestwich writes : — " The division of the Coal- 

 measures into separate basins appears to be their normal con- 

 dition along the great line of disturbance between the French 

 Coalfields and those in Somersetshire and South Wales. The 

 transverse ridges separating the different basins are subor- 

 dinate to the great east and west axis, and are never wide nor 

 long-maintained. The length of those portions of the axis 

 between West Pembroke and Frome, and between Calais and 

 Dortmund, is 472 miles, and in this distance there are eight 

 separate Coalfields of an aggregate length of 350 miles, 

 leaving only 122 miles occupied by intervening tracts of older 



