166 EEY. A. lEVrSTG OK THE STEATIGKAPHT 



Section IE. Brick-pit in Hagthorn Hill, Ascot *. 



feet. 



a. Clayey drift-material of the hill-slope 2 



h. Latninated clay-and-saud bed -with irony concre- 

 tions (No. 5) 7 



c. Laminated purplish clay with subordinated 



layers of greensand (No. 7) 1^- 



[On the east side of the pit c thickens to 4 feet and becomes 

 a normal green earthy sand.] 



d^. Laminated layers of purplish clay with very 

 little sand 1 



dr,. Gvey and green sand with subordinated layers 

 of purplish clay 1 



[(Zj and d.^ apparently = No. 8.] 



e. Hard chocolate-coloured shale, strongly laminated 

 with glauconitic greensand in patches and 

 small layers (^No. 9) 4 seen 



(/. Portion not exposed, representing No. 10) 6 



g. Fine quartz sand (No. 11) exposed to 4 



Total of section 26| 



[Bottom of this section about 250' O.D.] 



A slight dip to the south-east is observed in the beds in sections at 

 right angles in this pit ; a similar dip is observed in the railway- 

 cutting t nearl}' half a mile to the south-east of the pit ; and the 

 lower levels of the beds of the Middle Group at Windlesham point 

 to its continuation as far as that place. The dip is also percej)tible in 

 the railway-cuttings at Sunninghill. It gives us the pebble-bed 

 (1^0. 3), 2 feet thick, on the northern nose of the hill, about 

 290' O.D. 



Section jS". Cutting on tJie South-iuestern Railway^ Tialfway 

 hetween Ascot and Sunningclale Stations. 



feet. 

 ■a. Clay (=No. 5) 5 



b. Glauconitic green earths (Nos. 7 and 8) 14 



c. Strongly laminated light purplish and grey clay 



(-=No. 9) 6 



(No. 10 apparently wanting.) 



d. White and yellow fine quartz sand (No. 11), exposed 



to the level of the line 4 



Total exposure 29 



[The level of the line here is about 200' O.D.] 



Comparing the altitudes given in the foregoing sections for the 

 top and base of the Middle Group, there seems to arise a necessity 

 for inferring the existence of a slight anticlinal (seen to be very 

 slight indeed when drawn to true scale), with an axis running 

 nearly through BrackneU, Swinley Park, and Windlesham, and 

 inclining to the S.E. or thereabouts. This agrees with the general 

 rise of the base of the Middle Group as it recurs passing eastwards 



* Cf. Mem. Geol. Survey, vol. iv. p. 332. 

 t Quart. Journ. Geol. Soc. vol. xxxix. p. 349. 



