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DE. C. T. TBECHMAXX OX IXTEEOLACTAL [vol. lxXV > 



and of course in the concretions rises considerably in quantity. 

 The magnesia is rather high, and may have been partly derived 

 from some of the local Magnesian Limestones, but in the Bonn 

 sample I also found it to be relatively high. Alkalies were- 

 determined in two samples and found to be rather high, probably 

 owing to the quantity of mica in the material. 



Fig. 1. — Loess concretions, Warren -House Gill 

 (one-half of the natural size). 



Compared with water-deposited and Glacial clays from this 

 district which I have analysed, the Durham loess is noticeable in 

 physical characters by its absence of plasticity, its porosity and 

 light colour, and in chemical composition by its richness in silica 

 and calcium carbonate and its poverty in alumina. 



IV. Notes ox the Scaxdixavi.vx Boulder-Clay at 

 \Yaeeex-Holse Gill. 



During the winter of 1917-1S the Scandinavian Drift was well 

 exposed for several weeks on the foreshore between tide-marks along 

 nearly the whole quarter of a mile of the section, and on the occasion 

 of one particularly high tide the base of the cliff-section was washed 

 perfectly clean for almost the whole extent, when the undulating 

 line of junction of the Scandinavian with the overlying Cheviot 

 Drift could be very well seen. A few days later, however, heavy 

 rain washed the slipped clay from the cliffs above over it again, 

 and the section became more obscure than it was before. 



In the cliff-section the contortions of the upper layers of the 

 Scandinavian clay and of the redeposited lcess-like material, caused 



