390 PROCEEDINGS OF TIIE GEOLOGICAL SOCIETY. [May 6, 



materials were identical in substance and colour with those of the old 

 glacial gravel, but that it was wholly unstratified; whereas that gravel, 

 when in situ, is notably bedded. I had, therefore, a pit dug following' 

 the face of this talus until stopped by water. I found that the base- 

 ment gravel of the newer deposits runs underneath the talus, while a 

 sandy layer resting upon it, but markedly distinct, has the end of the 

 talus intercalated with it. All the beds above this rest against the 

 face of the talus, and have their ends slightly bent upwards against it. 

 A few pebbles lie upon the face of the talus, as if they had rolled down 

 it while the upper beds which abut upon it were being deposited. 



Passing upwards from the denuded surface of the peat, we next 

 meet with a deposit of sandy brown brick-earth (d), about 9 feet 

 thick. It differs entirely from all the beds below it, and was evi- 

 dently deposited by a comparatively quiet action against the face of 

 the old talus, which is wholly undisturbed by it, while its lines of 

 stratification bend upwards where they abut upon it. In this brick- 

 earth are a few very thin beds of pebbles. There are also, as already 

 noticed, a few pebbles where it joins the talus. In the former 

 position was found a singular red stone, which seems to have been 

 baked in fire *. In character the brick-earth seems like a silt 

 derived from the weathered surface of London Clay, abundant in the 

 neighbourhood. A similar bed of brick-earth occurs in some pits 

 near the Colchester railway-station, where it is nearly 20 feet 

 thick. I have obtained from it the teeth of Deer. 



The next deposit in ascending order is the capping of soil, or 

 " heading," passing upwards into the vegetable mould. Of this deposit 

 I believe less is known than of almost any other, while its import- 

 ance as containing the records of the latest geological changes ex- 

 ceeds perhaps that of many of the older strata. In the present 

 locality there seems to be sufficient evidence that it is a drift. Its 

 line of junction with the brick-earth is, as usual, extremely irregular ; 

 and its lower portion is here, as elsewhere, studded with small sub- 

 angular flints. Small flints occur only sparingly in the brick-earth 

 on which it rests. There is at present to be seen, intercalated in 

 the deposit, a thin wedge-shaped drift of sandy gravel, evidently 

 washed down from the old gravel forming the hillside above. At 

 the brick-pit near the Colchester station this drift in patches has 

 almost the character of a gravel, while the brick-earth on which it 

 rests is nearly devoid of pebbles. It seems impossible that the one 

 can have been derived by any subaerial action from the other. 



There is also at Lexden a section of a natural bank, beneath which 

 the surface of the brick-earth is seen to follow the form of the super- 

 ficial surface, with this overlying drift wrapping round it. 



Mode of Formation of the Strata. — In endeavouring to understand 

 the causes which have led to the phenomena just described, I have 

 been much assisted by noticing the present condition of the locality, 

 and have little doubt that the state of things during the period when 

 the Elephant lived here was only an older edition of the present. 



* Deposited in the Society's Museum. Mr. Prestwich has indicated Lexden as 

 a probable locality for " Flint Implements," Phil. Trans. I860, part 2, p. 308. 



