490 KEi'oiix— 1873. 



Appendix added hy the Committee, 2nd March, 1874. 



The Committee are of opinion that the problem of the Influence of Forests 

 on the Rainfall cannot be directly attacked, but must be preceded by a pre- 

 liminary inquiry into the temperature and humidity of the air of the forest 

 itself, as compared with the temperature and humidity of the air outside 

 the forest. The observations referred to above wiU supply these data. The 

 Committee also contemplate the placing of underground thermometers and 

 evaporometers at Stations Nos. I. and II., and the examination of the tem- 

 perature of the trees by means of thermometers permanently fixed in them, 

 in the manner adopted at the forest-stations of Bavaria. 



Report of Sub-Wealden Exploration Committee, appointed at the 

 Brighton Meeting, 1873, consisting of Henry Willett, R. A. 

 Godwin-Austen, F.R.S., W. Topley, F.G.S., T. Davidson, lUl.S., 

 J. Pkestwich, F.R.S., W. Boyd Uawkins, F.R.S., and Henry 

 Woodward, F.R.S. Drawn up by Henry AVillett and W. 



TOPLEY. 



The x'>i'opo.sal to commemorate the visit of the Association to Brighton bj' 

 some practical effort to extend the bounds of scientific knowledge was 

 received with unexpected favour, and the support given to the Sub-Wealdeu 

 Exploration has justified its selection as the most eligible unsolved scientific 

 problem in the south-east of England. This Report may bo considered a 

 summary of the transactions more fully detailed in the four quarterly reports 

 of the Honorary Secretary. 



The original project was for a bore of 6-1- inches ; but this was overruled 

 by the Committee in London, and the adoption of a diameter of 9 inches was 

 decided on. The opinion of Prench engineers of eminence was adduced by 

 Joseph Prest\vich, Esq., F.R.S., F.G.S., in favour of this increase, and pro- 

 bable success to the iiltimate depth required was considered more important 

 than the increased cost. The bore-hole has reached (at the full diameter of 

 9 inches) a depth of 300 feet, and the engineer has contracted to increase 

 it to the depth of 418 feet at the cost only of £1 per foot. The diameter of 

 9 inches may be considered merely the foundation of the work, and, like 

 all foundations, it makes but a small show for the money expended. 



The shedding, machinery, tools, and rods for a depth of nearly 1000 feet 

 have been purchased, but much time and money must be expended before 

 2000 feet or palasozoic strata are reached. 



300 feet of strata have already been examined : 70 feet are supposed to 

 represent the known Eounden-Wood beds ; 230 feet are new to science, of 

 which 50 feet consist of valuable beds of gypsum. 



Professor Eamsay states " no such beds of gypsum have hitherto been 

 found in Europe;" and Mr. Etheridge considers "that it is the most 

 important geological discovery made in England for the last twenty years." 



The cores exhibited prove, bj^ their horizontal bedding, that hitherto the 

 crest of the anticlinal axis has been undisturbed, fully justifying the 

 selection of the site. Mr. Topley explains more fuUy (in his accompanying 

 Report) the general geological features. 



