192 ME. J. A. BROW]^ ON THE THAMES- VALLEY 



15. The Thames-valley Sueface-deposits of the Ealing District 

 and their Associated Paleolithic Eloors. By John Allen 

 Beown, Esq., E.E.G.S. (Eead Jan. 27, 1886.) 



[Communicated by A. Eamsay, Esq., F.G.S.] 



[Abridged.] 



This paper, which is but a brief epitome of my investigations, may 

 be coDsidered as a supplement to the valuable one by Col. Lane 

 Eox " On the Palaeolithic Implements in Association with EJephas 

 lirimigenms in the Thames Yalley at Acton " *, so far as it relates 

 to much higher bench-deposits than those described by him. 



Mr. Whitaker has described the highest of the three terraces 

 into which he has divided the valley-deposits, as occupying the levels 

 between 50 and 100 ft. above 0. D.f, and extending up the shoulders 

 of the hills which, to the north of the river, divide the inner valley 

 from its wider extension of, generally speaking, low-lying Eocene 

 deposits, now bounded by the chalk hills of Herts and Bucks. I 

 shall now show that the high bench-deposits reach far above the 

 100-foot level ; this fact is, however, one which Mr. Whitaker is 

 evidently prepared for. 



The high-valley gravels proper in the neighbourhood of Ealing 

 flank the sides and, in some cases, reach nearly to the top of the 

 hills which form the inner-valley ridge. They extend from East 

 Acton (where the mid terrace runs up as a deposit which differs 

 altogether in structure from the higher one, and which appears to be 

 a redeposit of the older bed) to beyond Hayes, forming a continuous 

 tract to the north, which reaches much beyond the Great "Western 

 Eailway. 



The highest ground of the inner-valley ridge above mentioned is at 

 the Mount and Hanger Hill ; the former, which rises to 204 ft. above 

 0. D., is tbe site of the large reservoir made by the Grand Junction 

 Water Company. During the excavation, I found that the summit 

 of the hill was occupied by thick beds of gravel of a totally different 

 character, and formed under other conditions than a fluviatile or 

 estuarine gravel, and that patches occur here and there in such a 

 way as to render it probable that these gravels once extended right 

 along the ridge and over Hanger Hill. The results of my obser- 

 vations are given in a paper, which I read to the Geologists' Asso- 

 ciation X. The excavation disclosed long furrows filled with flint- 

 gravel and fragments of foreign rock, which were also spread over 

 the adjoining fields ; the underlying stratified beds of white sand 

 and loam (believed to be Bagshot) were always distinctly pressed 

 out of the line of deposit where the jagged furrows occurred ; it was 

 noticeable that the stratified beds became again horizontal at a 

 lower depth, thus showing that the formation was not due to the 



* Quart. Journ. Geol. Soc, vol. xxviii. p. 449. 



t Mem. Geol. Survey on sheet 7. 



:|: '■ Probable Glacial Deposits at Ealing," Proc. Geol. Assoc, vol. viii. no. 3. 



