452 PROCEEDIJTGS OF THE GEOLOGICAL SOCIETY. [MuV 24, 



gTavel was deposited by any " ancient river following the direction of 

 the present streams," because it contains Chalk-flints which are not 

 found in place until we have crossed the high Greensand escarpment, 

 and at a distance of seven miles. It must be recollected, how- 

 ever, that tributaries of the Eden rise at the Chalk near Titsey and 

 Godstone ; and the old gravel found near them is composed, as we 

 are informed by our colleague, Mr. W. Boyd Dawkins, of flints and 

 chert, brought down, no doubt, by the tributary streams. These 

 streams, then, probably furnished the Eden with the flints and Ter- 

 tiary pebbles * which are now found in its old alluvia. Again, 

 the Plaxtole Brook doubtless helped to furnish the flints and Ter- 

 tiary pebbles found in the Hadlow gTavel. On the eastern side of 

 the Medway basin, in the Weald Clay valley, where there are no 

 streams coming in from the Chalk, flints are very rare, and the 

 river-gravel is almost entirely composed of Wealden pebbles. This 

 fact is in favour of the theory that the flints at Hever and Hadlow 

 were brought down by tributaries coming from the Chalk. Mr. W. 

 Boyd Dawkins, who mapped the gravel at the eastern and western 

 ends of the Medway basin, has arrived at the same conclusion t- 



Rivers Beult and Teise. — Deposits of gravel are found along 

 the banks of both these streams, and in the angle formed by the 

 junction of the two streams a considerable spread of gravel is met 

 with. There are four patches of gravel lying at about the same 

 level, (50 or 60 feet above the rivers Beult and Teise), which appear 

 to have been once united, forming a broad plateau. Gravel was no 

 doubt deposited at the junction of the Beult and the Teise when 

 these rivers were at a much higher level and their junction further 

 south-east. As these rivers worked their way to the west and to 

 the north, the spread of gravel increased. The rivers at the same 

 time gradually cut their way down deeper ; their old beds were left 

 high and dry, and were at once attacked by the denuding agencies 

 of the atmosphere. Little valleys, some 20 feet deep, have been 

 cut through the gravel and the underlying clay, and all that remains 

 of the broad plateau are the four above-mentioned patches. 



Sections of the gravel are seen at Marden and at Wantsuch Green. 

 It consists almost entirely of pebbles of Wealden sandstone ; a 

 few quartz-pebbles J also occur, and occasionally a few flints are 

 met Avith. Sir R. I. Murchison, in his paper just alluded to, men- 

 tions the fact that remains of the Mammoth were found in the 

 gravel at Marden §. 



* Eeds of pebbles are found capping the Chalk escarpment near Grodstone, 

 believed by Mr. Prestwich to be unconformable Tertiaries (" On the Thanet 

 Sands," Quart. Journ. Geol. Soc. vol. viii. (1852), p. 256). 



t This is also shown by Mr. Prestwich in the map appended to his Memoir 

 in the Phil. Trans, for 1864. 



I Pebbles of quartz, as big as a hen's egg, are sometimes found on the Weald 

 Clay about Marden and other places, as well as being found in the gravel. 

 Whence these pebbles are derived is somewhat uncertain. 



§ I may add here that I found the pointed end of a flint-implement, of the 

 spear-head shape, in a field at Marden : part of the field was on the river-gravel. 

 I also found an oval-shaped flint hatohet on the surface of a field near Maid- 

 stone, though at some distance from any existing deposit of river-gi-avel. Both 

 implements resemble those that have been foimd in gravel. — C. L. N. F. 



