718 REPORT— 1892. 



SAT VB DAY, AUGUST 6. 



The following Papers and Reports were read : — 



1. On the Physical Oeology of Arabia Petrcea and Palestine. 

 Btj Professor Edwaed Hull, LL.T)., F.P.S., F.G.8. 



The author in this paper stated the results of the ohservations made during the 

 expedition sent out hy the Committee of the Palestine Exploration Fund in 

 1883-84, including the observations of previous travellers. 



After describing the physical features of the region traversed, the author 

 described the Archtean rocks of the Sinaitic and Edomite Mountains, succeeded 

 by the Lower Carboniferous sandstone and limestone of Wady Nasb ; succeeded by 

 the Nubian sandstone (Neocomian or Cenomanian), the Cretaceous and Nummulite 

 limestones, which form the table-land of Palestine and of Arabia Deserta. 



The relations of the Pliocene terraces along the coast, and those of the Jordan- 

 Arabah Valley, to the older formations were also discussed. 



The author concluded by describing the line of the great fault or system of 

 faults along the line of the Jordan-Arabah Vallev, and showed how this great 

 depression had (probably during the Pluvial period) been the basin of a lake, about 

 200 miles in length, during the period of highest level, and had extended from the 

 Wady-el-Arabah to the Lake of Merom. Conclusions regarding the climatic 

 conditions of the Pluvial period and the extent of aqueous erosion were stated. 



2. On Two Tunnel Sections in the Cambrian of Carnarvonshire. 

 By J. P. Blake, M.A., F.G.8. 



A section in the Penrhpi Slate Quarries, lately made, shows felsite, like that 

 of Llyn Padarn, in the midst of purple and other slates ; a position consistent with 

 intrusion or contemporaneity, but not with a pre-Cambrian age of the felsite, 

 except by the aid of hypothetical faults. 



The already described adit in Moel Tryfaen had been examined, and a conglo- 

 merate, similar to that of the summit, but only thirtv inches thick, had been found 

 between the purple and banded slates. This is considered to be probably different 

 from the more massive and wider spread mass on the summit, though no proof of this 

 is as yet offered. The conglomerate, however, is not at the base of the series in 

 any case, but is followed below by a long series of banded slates, Bangor breccia, 

 coarse grits, and a lower smaller breccia conglomerate. Amongst the grits are two 

 bands of felsite, possibly intrusive, but certainly not earlier than the grits, so 

 that the hill has, on the whole, very little felsite in it at all. 



3. Report of the Committee on the Volcanic Phenomena of Vesuvius. 



See Reports, p. 338. 



4. Report of the Committee on Elbolton Cave. — See Reports, p. 266. 



5. Interim Report of the Committee on the Excavations at Oldhury Hill. 



