Br. Nils Olof Hoist — The Ice Age in England. 437 



outside the periphery of the inland ice, and which, as will be shown 

 later, must have been laid down in a large deep basin formed by the 

 depression of Southern England. This depression was greater 

 towards the north and the east, less towards the south and west, and 

 may have reached as much as 200 feet below the present level. 



This loam must therefore have had, and indeed still has, a wide 

 distribution in Southern England, away from the northern boundary 

 of Essex into the valley of the Thames, and along the southern coast 

 right down to the Scilly Isles, where its presence has lately been 

 proved by Gr. Barrow. We also find its equivalent in the large 

 continuous loam tract in Belgium and in Northern France, of which 

 more later on. 



Concerning the loam in the Thames Valley, Mr. H. B. Woodward 

 quite correctly says that this "appears to have been deposited for the 

 most part in tranquil waters and has' been described as an inundation- 

 mud". It varies, he says, in thickness "from a few feet to 20 feet 

 or more "- 1 A characteristic of it is that it lies without any passage 

 on the older gravel, also that it is not to any noteworthy extent 

 washed out on the surface; whence it may be concluded that the water 

 from the loam basin was emptied out with considerable rapidity, an 

 important circumstance to which there will be occasion to refer later 

 on. In one locality, Green Lane brickyard, at Acton, London, W., 

 I have seen horizontal layers of sand and clay beautifully alternating 

 through the lower part of the loam, here 12 feet thick, but often the 

 fine clay goes right down to the bottom, to the gravel, 



While the gravel in the last-mentioned brickyard, as Mr. F. Sadler 

 kindly informs me, yields Chellean implements but never Mousterian, 

 the loam, on the other hand, contains only late Mousterian imple- 

 ments, that is to say, precisely the type which belongs to the 

 maximum of glaciation. 



Exactly the same situation as the loam of the Thames Valley is 

 occupied, just outside the moraine district, by the great tract of 

 loam which in North- West Essex extends over the peninsula between 

 the Eivers Stour and Colne. 2 Here too the lower beds may be sandy. 

 The highest points of this clay tract lie between 161 and 187 feet, 

 pointing to a corresponding depression during the deposition of the 

 loam, or more correctly a somewhat greater depression, since the 

 pure loam as a deep-water formation was never deposited on 

 the shore-line itself. This seems to have been the greatest depression 

 that affected Southern England during the stage in question. 



On the southern coast of England there have been proved still 

 older stages of depression than that during which the loam was 

 deposited, but before considering these a few words may be devoted 

 to the course of the depression taken as a whole. 



The fact has already been recalled that England, like the whole of 

 Northern Europe, during an earlier pre-glacial stage lay considerably 



1 H. B. Woodward, 1909. The Geology of the London District (Mem. Geol. 

 Surv. England and Wales), see p. 74. 



2 See the Geological Survey drift maps and memoirs, to which reference 

 may also be made for the following account of the Pleistocene deposits in 

 Southern England. 



