176 EEY. A. IEYnf& OlS THE STEATIGEAPHT 



The apparently excessive thickness of the Middle Group on this 

 hill- side is explained by a dip towards the Elackwater Valley, of 

 which evidence is given above. 



Beariuood Hills. — In addition to the facts already described (Geol. 

 Mag. dec. iii. vol. iv. pp. Ill et seq.) the following require con- 

 sideration, (a) The flank of the hill is very much obscured by a vast 

 amount of debris (mixture of sand and pebbles) from the higher 

 beds, the phenomena presented at St. Anne's Hill, Chertsey *, being 

 here repeated. There are several old, overgrown gravel-pits, in 

 which these materials have been worked in former years. 



(6) In the latter part of the summer Mr. Walter was good enough 

 to have a second and deeper square pit dug through the pebble-bed. 

 On descending the pit by a ladder, I made the following observations 

 and measurements, while the section was fresh and not obscured by 

 rain-wash. 



Section IJ. Pit on tlieflanh of BarTcham Hill (260' O.D.). 



ft. in. 



a. Drift (coarse sand and flint fragments) 2 



h. Loamysands 3 



c. Pebble-bed in greenish and brown sand 5 



<?. Coarse brown loam 3 



e^. Clay, tough, hard, pale grey, laminated 1 



e.^. Clay, more compact, chocolate-coloured 1-2 6 



63. Clay, tough, hard, drab-coloured, laminated J 



/. Coarse irony sand, with clay-laminre, like e 6 



g. Coarse sand, irony (similar to bed / in Section P, 



without the green sand) 3 6 



Total exposure 16 9 



The excavation was stopped by water, probably thrown out by beds 

 of the horizon of JN'os. 9 and 10, which may include the bed exposed 

 in a pit in the wood 300 yards north-west of this spot. The 

 beds e to g of this section I consider to be the attenuated equivalents 

 of the beds c to g of Section P (Wick Hill) t, on the other side of 

 the Barkham Valley, since in no other section have I met with clays 

 so precisely similar in character to the 2| feet of clay in this Eark- 

 ham section as the clays which in the Wick-Hill section are inti- 



* Quart. Journ. Geol. Soc. vol. xliii. pp. 376, 377. 



_t In reyising this paper for the press (March 5) I append the following note 

 with the specimens from the Wick Hill and Barkham pit sections arranged in 

 parallel faeries on a tray before me, the specimens of both series being equally 

 desiccated : — 



Bed d (Sect. U) lithologically identical with bed jS'o. 5, as exemplified by two 

 specimens from that bed as it is exposed in the railway -cutting at Wellington 

 College and in the adjoining brick-field. 

 Bed e^ (Sect. TJ) lithologically identical with clay-seams of bed c (Sect. P). 

 Bed e., (Sect. U) lithologically identical with bed d (Sect. P). 

 Bed gg (Sect. U) lithologically identical with bed e (Sect. P). 

 Bed d of Section U is seen on the south face of the pit, and thins away to 

 nothing in the transverse pit-face. The position of this bed is, so far as it goes, 

 in favour of assigning the pebble-bed to horizon IS'o. 3. 



