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ox A SECTION AT WALTON COMMON EXPOSING LONDON CLAY ETC. 1-17 



11. Oil a recent Section through Walton Common exposinrj the 

 London Clay, Bagshot Beds, and Plateau- gravel. By 

 W. H. Hudleston, Esq., M.A., F.E.S., Sec. G.S. (Read January 

 13, 18S6.) 



Introduction. 



During the past autumn the London and South- Western Railway 

 Company has been engaged in widening the line between AYalton 

 and Weybridge stations, and consequently there has been an excellent 

 exposure of the beds composing the Walton-Oatlands plateau. The 

 communication now made to the Society relates only to such portion 

 of the railway-cutting as extends from Walton station in a west- 

 south-west direction to the boundary of Oatlands Park, and more 

 particularly to that portion of it known as "America." The total 

 length, as measured on the 6-in. Ordnance map, is 1070 yards. 

 This distance is divided unequally by the railway bridge on Walton 

 Common known as " Sir Richard's." The distance between Walton 

 station and the centre of this bridge is 710 yards, whilst the distance 

 from this point to the boundary of Oatlands Park is 360 yards, or 

 thereabouts. 



For the purposes of description and convenience of reference, the 

 entire section may be divided into four blocks. 



Block A extends from Walton station to where the unaltered 

 London Clay in seen to occur in situ — a distance of 313 yards. 



Block B extends from this to the point where the Bagshot Beds 

 are first seen in situ — a distance of 345 yards. 



Block C extends from the above to the point where the Bagshots 

 are first cut through to the level of the line, and the hoUow filled 

 up with Plateau-gravel — a distance of 165 yards. 



Block D exhibits the relations of the Bagshots to the Plateau- 

 gravel, where the latter is most fully developed — a distance of 247 

 yards. 



The above divisions are shown on the generalized section (fig. 1), 

 which may be regarded as a summary, on a small scale, of the 

 sections presently to be detailed. It must be borne in mind that, 

 owing to the exaggeration of the vertical scale, a certain amount 

 of distortion is inevitable. 



A few remarks on the topography of the district, and on the 

 formations composing it, together with a brief notice of the litera- 

 ture, may be of use in the first instance. 



Walton station is 17 miles from Waterloo ; it is situated about 

 midway between the 50-feet and the 100-feet contours (see fig. 2), 

 arid lies within the drainage of the river Mole. The line is 68 feet 

 above 0. D. at this point. The 100 feet contour is reached at the 

 bridge, where the cutting is estimated to have a depth of 24 feet. 

 At Weybridge station the surface of the ground is marked as 120 

 feet above 0. 1). Hence the plateau traversed by the railway, which 

 we may call the Walton-Oatlands plateau, ranges from a little 

 under to a little over the 100-fcet line, forming a low massif or 



Q. J. G. S. No. 166. M 



