1867.] WOOD SOUTH-EAST OF ENGLAND. 411 



the iluviatile beds of the underlying brick-earth (^4'), or of the 

 newer (or x 5) series succeeding the principal or inlet gravel, that 

 the moLluscan and mammalian remains brought to notice from time 

 to time have been obtained. 



It would carry me beyond the compass of this paper to examine 

 the way in which the beds of the series cv 5 have been followed by 

 the denudation of the Weald ; but all will, I think, admit that, if it 

 be evident that both the marine (or x 4) portion and the iluviatile 

 (cc 5) portion of the Thames gravel had no connexion with the present 

 river Thames, or with what is now the North Sea, but was dis- 

 charged towards the Chalk country, then the excavation of the Weald 

 vaUey, and the formation of the beds within it, must be of posterior 

 date. In proof of that sequence I invite those who are sceptical 

 upon the point to study the structure and position of the gravel 

 relatively to the trough containing it, and to submit the mapping and 

 structure of it shown in my memoir and survey to a rigorous and 

 exhaustive examination, and to point out in what way the struc- 

 ture and position of the gravel can have any connexion with the 

 river Thames or with its valley as it opens to the North Sea. 



A section (fig. 14) drawn across the eastern embouchure of the 

 Thames-gravel channel, the embouchure of the channel of the East 

 Essex sheet, and that of the channel of the Canterbury -heights gravel, 

 as the three originally opened to the sea of the south, together with 

 the same section, as it now appears from the break-up and denuda- 

 tion, may assist in rendering the views discussed more intelligible*. 



In the memoir I have endeavoured, by pursuing the denudation 

 from stage to stage, and by connecting with it the various detached 

 beds of Postglacial gravel occurring in the area, to trace the man- 

 ner in which it has progressed subsequently to the break-up of the 

 Thames gravel ; and in doing so I have been led to the conclusion 

 that the gravels in which the flint implements have, up to this time, 

 been found, belong to a stage at least as much newer than the 

 Thames beds as these are newer than the Glacial clay f, notwith- 

 standing that these gravels, in Bedfordshire and west Norfolk, hap- 

 pen to occur in troughs cut down from the Glacial beds, and that to 

 a smaU depth only, when compared with the trough containing the 

 Thames beds. In the south of England, as, for instance, at Salisbury, 

 these implement-gravels occupy that position which, in following 

 the denudation from its commencement in the Upper Glacial clay 

 through the Thames-gravel series into the Chalk country, indicates 

 that they are divided from the latest part of the Glacial period by the 

 interval occupied in the denudation of the Tertiary beds and the 

 Chalk do^.vn to the Lower Cretaceous formations ; for, although these 



* I am indebted to Mr. Whitaker, of the Geological Survey (who has mapped 

 the part of sheet 3 in which the eastern portion of this section occurs), for de^ 

 tails made use of in that portion of it. 



t Of course, I only refer to the implement-gravels yet made known ; hereafter 

 it may be discovered that man was coeval with some earlier gravel-period ; bvit 

 at present none of the beds belonging to the earlier part of the Postglacial period 

 have yielded flint implements. 



VOL. XXIII. PART I. 2 E 



