ON UNDERGROUND TEMPERATURE. 29 



posed that man placed them -where they were found under the foregohig con- 

 ditions ; for the bottom of the valley being then far above the low-level 

 entrance, the passages into which it immediately opens were probably inac- 

 cessible, and certainly not available for human resort. On the other hand, 

 the hypothesis that the flints were washed there from the upper chambers 

 appears to be entirely negatived by the fact that, though lodged in a deposit 

 largely charged with stones, they are entirely unrolled and retain their keen 

 edges. It may be added that very few, if any, of the bones found with them 

 show any marks of abrasion, that the implements are more numerous at and 

 near its external entrance than elsewhere in the Sally-port, and that no such 

 phenomenon presented itselt at or near the end of the other Sally-port, which 

 has no external moiith. 



May not the following be the solution of the problem ? The implements 

 and animal-remains found at the new entrance and in the passages connected 

 with it were deposited after it had been laid bare, and are chronologically 

 separated from those in the high-level chambers by an amount of time suffi- 

 cient to deepen the valley to the extent of 20 feet, but not sufficient to make 

 any change in the fauna of the district, or in the character of the implements 

 which its human dwellers employed. 



Mr. Ayshford Sanford has continued his identification of the fossils during 

 the past twelve months, and has examined a large number of them. Tlie 

 present state of his health has unfortunately prevented his sending in a 

 Keport. 



Third Report of the Cmnmittee for the purpose of investigating the rate 

 of Increase of Underground Temperature downwards in various 

 Localities of Dry Land and under Water. Drawn up by Professor 

 Everett, at the request of the Committee, consisting of ^\v William 

 Thomson, F.ii.S^., Sir Charles Lyell, F.R.S., J. Clerk Maxwell, 

 F.R.S., Prof. Phillips, F.R.S., G. J. Symons, F.M.S., Dr. Balfour 

 Stewart, F.R.S., Prof. Ramsay, F.R.S., A. Gteikie, F.R.S, James 

 Glaisher, F.R.S. , Rev. Dr. Graham, E. W, Binney, F.R.S. , 

 George Maw, F.G.S., W. Pengelly, F.R.S., S. J. Mackie, F.G.S., 

 and Professor Everett, D.C.L. (Secretary). 



Me. G. J. Stmons, whose observations, extending to a depth of 1100 feet 

 in a weU at Kentish Town, were reported at last Meeting, has since repeated 

 his observations at several depths. 



The first 210 feet of the well (which is 8 feet in diameter to the depth of 

 540 feet) are occupied by air ; and in this portion of the well the second series 

 of observations give temperatures exceeding those observed in the first series 

 by from 2° to 5° F., the excess diminishing as the depth increases. The second 

 series were taken in July and August, whereas the first series were taken in 

 January. It is evident that in this portion of the well, in spite of the pre- 

 cautions taken to exclude atmospheric influences, by boarding over the well 

 and erecting a hut over it, the temperature varies with the seasons, the 

 variations being in the same direction as in the external air, but smaller, and 

 diminishing as the depth increases, but still amounting to 2°-2 at the depth 

 of 200 feet. 



