W. WHITAKER ON SOME BOEINGS IN KENT. 27 



and it is to the second boring that this paper chiefly refers, because 

 of the unforeseen result. 



One would have thought that Chatham was favourably placed for 

 getting a large supply of water from the Lower Greensand, which 

 formation has a broad outcrop only a few miles to the south. It 

 was therefore with some surprise that one heard that, after passing 

 through only 41 feet of sandy beds (below the Gault), a mass of clay 

 was reached at the depth of 943 feet. 



At first this clay was naturally taken to bs either a very clayey 

 development of the Sandgate Beds (an idea soon abandoned), or 

 Atherfield Clay, or Weald Clay, this last seeming to be the most 

 likely, as it crops out from beneath the Lower Greensand in strong 

 force to the south *. The specimens of the clay, however, were not 

 quite like what would be expected from Weald Clay ; but no little 

 astonishment was felt when such of the small fossils in it as could 

 be made out were determined to belong to Oxford-Clay species. 



This was first suggested by Mr. J. P. Creswick, to whom the 

 Geological Survey is indebted for information and assistance in this 

 subject, and who had washed some of the clay at the Admiralty 

 Office of Works. It was fuUy made out by Mr. G. Sharman in 

 August 1884, when he recognized a s])eeiTa.eTL of Ammonites crenatus, 

 from a depth of 958 feet. Other specimens of Oxford-Clay species 

 have since been found higher up, to 925 feet from the surface, and 

 therefore we may safely include the whole of the clay (beneath the 

 Lower Greensand) as belonging to that formation, especially as it is 

 of much the same character throughout. 



Since this paper was written (February 1885), Prof. Judd has 

 referred to the subject f, remarking that the fossils prove that we 

 have to do with the middle part of the Oxfordian, the zone of Am- 

 monites Lamherti. 



The question of the advisability of continuing the boring having 

 been referred to me by Mr. Bristow, I reported thereon (29th ]S"o- 

 vember, 1884), concluding as follows : — " As a question of scientific 

 interest, and one, probably, of great practical importance (in view 

 of the possibility of the occurrence of Coal Measures), the continu- 

 ance of the boring is highly to be desired ; but as a question of 

 getting water, it can hardly be recommended. One would expect the 

 underground ridge of older rocks (that has been proved under 

 London &c.) to be met with, and, perhaps, at no great further depth 

 .... but what formation .... would be found seems be3'ond con- 

 jecture." In a later communication, again (after having been in- 

 structed to prepare a paper on the subject), I ventured to say that 

 my own personal opinion was that the boring should be carried on, 

 as an experimental boring (apart from the question of water-supply), 

 and, at the same time, I suggested that if a large amount of the 

 cores from the boring had been kept at Chatham, and were to be 



* See Topley, in the discussion on Prof. Judd's paper, Quart. Joum. Geol. 

 See. vol. xl. p. 763 (1884). His opinion, howeyer, was based only on some very 

 * small specimens. 



t Quart. Joum. Geol. Soc. vol. xH. pp. 526, 527. 



