S. V. Wood,jun. — American and British Surf ace- Geolog y. 547 
In one part of the South of England, the gravels which in my 
view represent the Upper Glacial ränge also to elevations between 
600 and 700 feet, as at Cassar’s Camp, near Aldershott, and other 
detached hill-summits N.N.W. of it, but elsewhere, as at Headon 
in the Isle of Wight, 1 at St. George’s Down in the same island, 
at Chilworth Tower, Stony Crop, and Bramshaw Telegraph in 
Hampshire, 2 and at Swanscombe Hill in Kent, the limit of their 
elevation ranges from 300 to 420 feet. Such of these sunnnit 
gravels as lie north of the Chalk district that divides the Hampshire 
from the London Basin may be all continued by numerous other 
gravel-topped eminences of less altitude across the counties of Berks, 
Buckingham, and Hertford in the one direction, and across the 
Thames Valley in another, into contiguity with the unwashed 
moraine which the chalky clay represents. 
The elevation attained by the gravels in the Cotteswolds probably 
affords a measure of the extent of the submergence in that direction, 
as these are remote from the theatre of submarine disturbances 
which have so elevated the gravels of the South of England. From 
the description given by Mr. H. B. Wood ward of the Devonshire 
gravels, this submergence does not appear to have diminished for a 
long distance further south-west. The elevation of the gravels 
over the South of England (Surrey, Hampshire, etc.), however, 
affords, in my view, no measure of the depth of the sea in that 
direction, because these gravels attain greater and greater elevations 
as they approach the points where the highly inclined position of 
the chalk shows the region to have undergone great elevation rela- 
tively to the rest of the gravel-sheet before so much of it was de- 
stroyed hy the denudation resulting from the disturbances producing 
this exceptional elevation. A study of the position of these gravels 
in Hampshire, Surrey, Berks, and Kent has convinced me that the 
sea under which they accumulated was not deep ; and that though 
it covered in a general sense the whole of the South of England, 
there were many islands over that part of Britain formed by such of 
the higher hills as had come into existence before the Glacial period, 
and were not, as were the Hogsback ridge and the Purbeck and 
Wight anticlinals, produced by the disturbances of this period. 3 It 
1 Geol. Surrey Memoir on the Isle of "Wight. 
2 Codrington, Quart. Journ. Geol. Soc. vol. xxvi. p. 528. 
3 I have in various papers during twelve years past, and particularly in one on the 
Weald Valley denudation in Quart. Journ. Geol. Soc. for 1871, urged that the dis- 
turbances in which the rectilinear upcasts of the Isles of Wight and Purbeck, as 
well as those of the Hogsback and Portsdown Hills, originated, took place at this 
time ; viz. the close of the Glacial period and beginning of what we in England 
have been accustomed to call the post-Glacial; and it is interesting to me to find that 
Mr. Prestwich, in a paper read in the year 1874 (Q. J. G. S. vol. xxxi. p. 29), makes 
out that during the Glacial period that portion of the Purbeck and Wight anticlinal 
which is continued north of Portland Isle was submerged, and then upheaved and 
suhjected to excessive deundation, though he does not admit the general submergence 
of the South of England. 
The section given in the Geological Surrey Memoir of the Isle of Wight through 
Headon Hill, with that in the Memoir on the London Basin through Caesar’s Camp 
(vol. iv. p. 376), are, it seems to me, not reconcilable with anything less than this 
general submergence ; and show to my mind clearly the excessive denudation which 
