450 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [May 24, 



The top of the terrace is rather more than 40 feet above the level 

 of the Medway. The gravel-pit a little north-east of Aylesford 

 Church will be known to many geologists, as it has yielded such an 

 abundant harvest of Mammalian remains. 



The gravel here is from 18 to 20 feet thick, and rests on the top- 

 most part of the Lower Greensand (Folkestone Beds). It consists 

 of angular and subangular bits of flint, Tertiary pebbles, pieces of 

 chert and Kentish Rag, and pebbles of Wealden sandstone, and large 

 lumps of sandstone resembling " Greywethers." It is interstrati- 

 fied in places with beds of coarse sand, and beds of loam are occa- 

 sionally met with. 



Bones or teeth of the following Mammals have been found in the 

 Aylesford gravel : — 



Elephas primigenius, Equus. 



Ehinoceros, 



The teeth of the Elephant are very common ; and occasionally 

 very fine tusks are found. 



The next well-marked terrace on this bank of the Medway occurs 

 on the top of the hill half a mile north-west of Maidstone Gaol, at 

 a height of 200 feet above the river. Its position is shown in fig. 2, 

 p. 451. It consists of angular and subangular bits of flint and 

 chert, with Tertiary pebbles and pebbles of Wealden sandstone : it is 

 distinctly stratified. On the left bank of the Medway, near Maidstone, 

 there is a good deal of gravel, occurring in three or more terraces 

 up to the level of 300 feet above the river*. The gravel exactly 

 resembles that found on the opposite bank, and we need only notice 

 that which occurs at the higher levels. About half a mile east of 

 East Mailing Heath, gravel is found at a height of 300 feet above 

 the Medway ; it contains pebbles of Wealden sandstone, flints, 

 chert, and Tertiary pebbles, and resembles undoubted river-gravel. 

 At East Mailing Heath, at a height of 275 feet above the Medway, 

 there are some beds of brick-earth with a little gravel, which have 

 been proved to be 36 feet thick in places. One of the pits shows 

 a beautifully stratified deposit, which few persons would deny to be 

 of true river origin. This brick-earth probably lies in a " pipe," 

 like those to be described hereafter. 



b. Tributaries of the Mechvay : River Eden. — The first tributaiy 

 of any importance is the River Eden. Sir R. I. Murchison, in his 

 paper "On the Flint Drift of the South-east of England "f, has 

 described some gravel at Hever Lodge, on the left bank of the Eden, 

 and gives a section showing its position. The gravel resembles that 

 of Aylesford, and in appearance and lie seems to be a true river- 

 gravel. Sir Roderick, however, in his paper, will not admit that this 



* These terraces, except the highest (of which little now remains), appear, in 

 tracing them down the valley, to fall to a lower relative level as compared with 

 the river beneath. The cause of this is not at all clear. Mr. Prestwich (Phil. 

 Trans. 1864, p. 252) has noticed the same fact in the valley of the Waveney. 

 Mr. Bristow informs me he has also observed it in the terraces of gravel in the 

 Thames valley. — W. T. 



t Quart. Joiirn. Geol. Soc. vol. vii. (18.'>1) p. 381. 



