NATURAL HISTORY NOTES 
55 
forming the highest ground in the district really represents the lower levels at the 
time of the deposition of the bed ; they thus speak for that antiquity which so 
vastly antedates the lower gravels of the valleys. _ 
Point No. 2 : This again is a question the answer to which is curtaded by 
space, but the materials found in the plateau beds offer some evidence as to the 
physical geography to which they owe their being. Mixed with the flints are 
pieces of greensand which must have come from the greensand outcrop to the 
south of the Downs before the present valleys were excavated. The same remark 
also applies to the fragmentary gault fossils found by my friends, Messrs. Harrison 
and Kennard, on the North Downs at an altitude of 760 feet above sea level. 
send a section of the North Downs showing the dip of the Secondary rocks, 
and it will, I think, be of use in illustrating the first position of the greensand 
fragments before they were detached from their beds and swept down the slope 
to the places they now occupy. This, then, constitutes one point of the evidence 
for the former physical geography which the writer asks for. 
As to point No. 3, its answer is foreshadowed by the foregoing remarks. 
There are, it is true, some stones marked with scratches which have been adduced 
as argument against the pre-glacial date of the deposit, but at the same time all 
the flints show signs of roiling not distinguishable in effect from the low level 
gravels. That the worked flints have been subjected to rolling after the period 
of their artificial shaping does not admit of doubt. The flints showing strife bear 
only a small proportion to the number contained in the beds, a point of some 
importance when it is remarked that nearly all of them, both worked and 
unworked, show imperfect conchoidal fractures. If the surface of an Eolith is 
carefully examined with a glass the more exposed portions will be seen to bear 
these characteristic marks of water action. Again an implement from the low 
level gravels shows a surface in some cases entirely covered with the fractures, 
and a further illustration may be made from the flinty shore pebbles, where the 
fractures are so numerous that they conceal the structure of the pebbles. It is 
therefore fairly evident that the agency which caused the fractures on the shore 
pebbles also produced those on the low level and plateau gravels, namely, the 
action of running or agitated water. The smaller fractures on the Eoliths seem to 
suggest less velocity, and therefore less transporting power in the stream which 
deposited the material, and this is quite in accordance with the composition of the 
clay matrix in which Eoliths are found. Patches of clay are not often seen in 
the valley gravels, the greater velocity of the stream, as evidenced by the larger 
fractures on the flints, probably being sufficient to account for the absence of 
such material. It had not, however, sufficient transporting power to still hold in 
suspension the innumerable small flints packed between the larger stones. 
I may perhaps be allowed to disclose a desire to know what is meant by your 
