W. WHITAKER OK SOME BORINGS IIT KENT. 39 



section, which gives a thickness of only 9| feet more than the lowest 

 of the above figures (192). 



So far, therefore, nothing occurs to cause any surprise ; but when 

 we reach the Lower Greensand we are faced by new facts, though 

 at first these are not particularly startHng, as in sands one expects 

 some irregularity. At the same time one would not have expected 

 that the Folkestone Beds (the sands that form the uppermost divi- 

 sion of the Lower Greensand) would have thinned away to 30 feet 

 from the 100 feet at their outcrop to the south, the nearest point of 

 which is less than seven miles ofi^. jS'o surprise would have been 

 felt, however, if the more clayey Sandgate Beds, always thin and 

 often inconstant, had been absent (as they are practically over the 

 outcrop of the Lower Greensand to the S.W.) ; but they seem to be 

 well represented by 11 feet of sandy clay, a thickness that compares 

 fairly with that at the outcrop on the south. 



After this, however, every previously known formation of the 

 county of Kent is absent, and we are confronted by the total disap- 

 pearance underground of beds that are well developed at their outcrop 

 near by to the south, where, indeed, some of them occur in their 

 greatest force. 



Taking the absentees in downward order, we have firstly the 

 Hythe Beds, with a thickness of 70 or 80 feet near Maidstone, the 

 head quarters of the Kentish Rag (the most characteristic state of 

 this division of the Lower Greensand). Their nearest point to the 

 boring is but just over 7 miles, and they are thicker to tlie west. 



Then of the thin clay that has been classed as Atherfield Clay, 

 and which is some 15 feet thick in the Maidstone district, there is 

 no trace. 



The next formation wanting is the "Weald Clay, the nearest 

 outcrop of which is at the inlier at Maidstone, some nine miles away, 

 where too it has proved to be 600 feet thick, in a boring. In the 

 light of our new facts, however, one may perhaps question whether 

 this 600 feet is really all Weald Clay, although that thickness 

 seems not too great for the main outcrop a few miles to the south. 

 The record is an old one, and probably specimens do not now exist ; 

 so we must be content to leave this question, and to accept the old 

 reading. 



Having now got rid of some 700 feet of beds, which crop out at 

 no great distance from Chatham, we are prepared to lose the rest of 

 the Wealdenbeds, which occur further off'; and, indeed, one would be 

 surprised if, in the absence of the lower part of the Lower Greensand 

 and of the Weald Clay, any members of the Hastings Beds were 

 represented. These increase our deficiency as foUows : — The Tun- 

 bridge- Wells Sand by about 160 feet, the Wadhurst Clay by about 

 the same, and the Ashdown Beds, the base of which is rarely seen 

 in the AVeald (and then in Sussex), by probably at least 400 more. 



To continue, we have no trace of the Purbeck Beds, which, near 

 Battle, underlie the last, with a thickness of over 300 feet ; so that 

 more than 1000 feet is added to the 700 above mentioned, and to 

 this respectable total of over 1700 feet, nearly as much can be 



