384 



EEV. A. TRVIXG ON THE PHYSICAL HISTORY OF 



is obtained from a fine quartz-sand resting on London Clay. There 

 is no record of a passage-bed. The sharp distinction between the 

 sands and the London Clay (see fig. 4, vol. xli. p. 505) is borne out 

 by excavations on the cutting-slopes, and by my observation of open 

 graves in the churchyard. 



Elevation of Beds due North from Wellington College. 



Section E. Valley | mile North of Wellington College. 



Preferences to numbers in well-section (Quart. Journ. Geol. Soc. 

 vol. xli. p. 494, fig. 1). Corrected altitude 287, O.D. 



ft. 



No. 3. Pebble-bed in stiff loam (about) 2 



No. 4. Coarse loamy ferruginous sand with irony concretions 3 



No. 5. (Wanting.) 



No. 6. Strong loam and clay (brick -material) 6 



Nos. 7, 8. Green earths throwing out springs about the middle and at the \ 



base J 



Nos. 9, 10. Clay-and-sand beds, more sandy in the middle, not distinctly j 0 q 



differentiated, coarse and ferruginous, with irony concretions... J " : - 

 No. 11. Fine sharp quartz-sand, with glassy silica (depth) ? 



There are several exposures of one or more of these beds a little 

 way east and west of the road, and they can be traced to the brook 

 to the west (section B). Nos. 9 and 10 are cut through in the valley, 

 and are exposed on the north side of it by the road ; but further to 

 the east they form a higher feature of the ground, and extend across 

 Nine-mile Bide, on the south of which about 5 ft. are exposed in a 

 brook-section, while on the north side of the road the clays of these 

 beds are worked in the new brick-yards. The same fine quartz-sand 

 is proved here beneath them in several wells and trial-holes. The 

 clay-beds here, with their included irony concretions, are identical 

 in character with those dug at the California brick-kiln (see infra, 

 p. 385) ; and both are identical with bed b (no. 10) in the well 

 (section C, p. 382). On the west side of the New Wokingham Boad 

 beds nos. 9 and 10 form the higher feature of the ground by Heath- 

 lands (base of no. 10 exposed in a sand-hole) and St. Sebastian's 

 Church, where the graves pass through 5 ft. of no. 10 into the fine 1 

 quartz-sand of no. 11. 



The general strike of no. 10, so far as it can be made out, and \ 

 the outcrop of the London Clay (I have verified the mapping) along j 

 the small valley south of Bouse's Farm, Easthampstead, gives less 

 than | mile for the outcrop of the 95 ft. of the sandy beds nos. 11, 12, 

 13, of the well-section ; and this, by ordinary rules of stratigraphy, 

 would give something like 1000 ft. for the thickness of the London j 

 Clay and Beading Beds, as calculated from the outcrop of the Chalk 

 at St. Lawrence- "Waltham, 6 miles due N., if those three beds main- 



