94 THE EEV. H. G. HAXL, F.S.A., 



or -1875 of an inch ha^-ing been accumulated at a low estimate 

 in the eleven years which have elapsed since the board had been 

 placed in position, we arrive at a rate of annual deposition of 

 •017 of an inch. Tlien the five feet for the outside thickness of 

 the stalagmitic floor of Kent's Hole or Cavern would have been 

 formed in tlu-ee thousand five huncbed and twenty years at this 

 particular rate ; and the lower floor would be represented by 

 eight thousand four hundi-ed and forty-eight years for its maxi- 

 mum thickness of twelve feet. Eut this goes on the improbable 

 supposition of a uniformity in the rate of formation of the deposit, 

 and would give under twelve thousand years for the entire depo- 

 sition instead of Mr. 'Wallace's three liuiuli'cd and fifty thousand.* 



The well-known Jockey Cap stalagmite in the beautiful Ingle- 

 borough Cave, Yorkshire, has become, in the able hands of Mr. 

 Farrer, and the late Professor Phillips, a kind of gauge of the 

 rate of such accumulation. Here the annual deposit fi-om 1845 

 to 1873 was not less than -2946 of an inch. And that which 

 Prof. Boyd Dawkins has remarked of the great stalagmite of the 

 Ingloborough Cave seems generally true of all similar calcareous 

 deposits. The diip containing the carbonate of lime may be in- 

 termittent, not continuous. In 1845 Professor Phillips estimated 

 its age at two hundred and fifty-nine years, on the supposition 

 that all or nearly all of the carbonate of lime in each pint was 

 deposited. According to its present rate of gi'owth, however, 

 one huntli'ed years woukl be amply sufficient, and at the same 

 rate we need not go further back than the time of Edward III. 

 for tlie date of all the stalagmites and stalactites in that beau- 

 tiful cavern. 



On the need of the avoidance of any such hasty generalizations 

 a8 those of Mr. Wallace, I may cite some weighty cautions of 

 one who has most thorouglily studied the subject in connection 

 with this last example wliich I have adduced. ** It is evident,! 

 from this instance of rapid accumulation, that the value of a layer 



* Reckoninf; tlic deponit Kh a quarter of an inch on the lower boards the times required 

 would >)•■ two thouvnnd nix l>uivlre«l nnd forty, and six tlionsnnd three hundred and thlrty- 

 %\x yeari renpcctlvoly, or nearly nine thoutund yeart* in all. 



f Cjivc-IIuntinj.', ("hap. II. p.p. -li» .iiul II. 



