300 Florence J. Relf—Some Wealden Sands. 
position, and not from any intermediate sandstone. The only sand- 
stone which need be considered in this connexion is the Trias of the 
West and Midlands; but according to Dr. Thomas’ the quartz grains 
in this formation are more rounded than those of the Wealden Sands, 
not less so, as must have been the case if the Wealden material had 
been carried from the Trias areas. Further, it is probable that, at 
that time, the Trias rocks were covered by Jurassic deposits which 
have since been denuded. Any river flowing eastward from the 
western land would naturally flow over these Jurassic rocks, and would 
carry away some of their material. That so little of it is now found 
in the sands would be explained by its generally calcareous nature. 
Some interesting specimens were found, however, in the Ashdown 
Sand from the neighbourhood of Lindfield, whose nature seems to 
indicate a derivation from Jurassic rock. In a sandpit north-east of 
Lindfield, east of Paxhill (the most westerly area considered in the 
Wealden district), is a layer in which the size of the fragments reaches 
i_1", They are, in fact, small pebbles firmly cemented to form 
a conglomerate. The pebbles in this conglomerate have been 
examined in microscope slides, as well as in the hand-specimen, and 
are found to consist mainly of quartz, some being vein quartz. But, 
in addition to these, are certain small lumps of white earthy-looking 
material. These are evidently the fragments to which Topley refers 
as ‘‘white chalky-looking stuff’.? Some of it breaks easily in 
a powdery fashion, but it is not soluble in HCl, and when the 
hardness of some of the less powdery pieces was tested it was found 
impossible to scratch them with a penknife. ‘The white material is 
evidently not calcium carbonate. In some pieces the powdery 
character is confined to the outside, the inside appearing chalcedonic. 
Under the microscope the white crumbly stuff was found. to have 
a great resemblance to decomposing chert, and a gradation seemed. 
traceable from this to a normal chert pebble. This discovery led to 
a comparison with several slides* of Jurassic chert from the Vale of 
Wardour and the Isle of Portland, and the comparison confirmed this 
opinion and showed that the Lindfield fragments closely resemble 
the Isle of Portland chert. Further search with a lens, in the hand- 
specimens, and with microscope revealed small pebbles with the 
oolitic structure and decided cherty appearance common in these 
Jurassic rocks. (Pl. XII, Fig. 6.) The presence of this material 
therefore strengthens the view that the water bearing the Ashdown 
Sands came from a westerly direction. 
It may be noted here that at Lindfield there are found a greater 
proportion of heavy minerals, larger fragments, and more variety 
of material—especially among the heavy minerals—than there are 
elsewhere in the Weald. This points to the probability that here we 
are near the middle of the old Wealden Channel. 
The west to east extension of the Wealden beds gives additional 
1 Dr. H. H. Thomas, ‘‘ Petrography of the New Red Sandstone’’: Q.J.G.S., 
1909. 
2 W. E. Topley, The Weald (Survey Memoir), p. 84. 
* These slides were kindly placed at my disposal by Dr. C. A. Raisin at 
Bedford College. 
