152 ME. W. H. HUDLESTON OlST A SECTION THKOUGH 



remainder of block A, with the exception hereinafter to be men- 

 tioned, is made up of this series overlain by 2 or 3 feet of a " Top 

 Sand," rather flinty in its lower parts. This mixed gravel and clay 

 makes a very wet line hereabouts. At the point n (192 yards from 

 the station) the following section was disclosed : — 



ft. in. 

 Made surface of old path 4 



(y) Top Sand, sometimes with bleached flints towards 



the base 3 



(x') Clay, sand, and pebbles with bleached flints 2 10 



Total 6 2 



The succeeding 50 yards discloses still more of this curious 

 mixture. A.s a whole, its character is strongly argillaceous, but 

 neither on the line nor in the section can a blue clay be discovered. 

 Lumps of brownish clay with pebbles occur in the midst of the 

 sands. Some of these lumps may be in continuity with the London 

 Clay beneath ; but, so far as we can judge from this section, the 

 whole must be regarded as a disturbed series, and classed with the 

 superficial deposits. 



At the point marked o (about 240 yards from the station) the 

 clay and sand with pebbles or "mixed series " is jammed against 

 the end of an included mass of what appears at first sight to be 

 yellow Bagshot Sand. The true nature of this mass of sand, 70 yards 

 in length, fully 12 feet thick at the west end or " corner," and taper- 

 ing to about 2 feet at the east end, is by no means clear. If we 

 examine it where narrowest, it can be regarded as nothing more than 

 a tongue of sand in the " mixed series," since the gravel underlies it 

 as well as overlies it ; but further up, where it gets thicker, nothing 

 can be seen to underlie the mass, of which the lowest visible bed is 

 a wet sandy loam. Where thickest, the yellow sand is much current- 

 bedded with inclination towards the east, but chiefly in the middle 

 and upper portions. The sand of these false-bedded portions is in 

 no respects like the sand of the main mass of the Lower Bagshots, 

 being entirely devoid of ihe laminated character, and also having 

 the grains larger and more unequal. It has more resemblance to 

 the lowest bed of the Lower Bagshots (No. 1) presently to be de- 

 scribed, but is coarser and more unequal in the grain. Both, how- 

 ever, are sharp, clean sands, in comparison with the "soft sand" of 

 the main mass of the Lower Bagshots hereabouts. It is a singular 

 accident that the almost ubiquitous " Top Sand " is absent where 

 this mass comes to the surface. The whole terminates in a most 

 remarkable and sudden manner (see flg. 3, junction of blocks A & B, 

 313 yards from the station) against an equally sharp and sudden 

 rise of London Clay covered by Plateau-gravel. The space between 

 the clay and sand is filled with a mixture of gravel and loose yellow 

 sand, and this gravel passes for some distance underneath the solid 

 mass of yellow sand itself. 



The above remarks are strictly descriptive, but the " mixe^ series " 

 and the sudden termination of the yellow sand cannot fail to provoke 



