ITS VARIOUS FORMS 21 



dents of its deposition. At one time it appears as a 

 superficial mass of unstratified rubble or breccia in 

 hollows or on slopes, at another as a breccia in fissures, 

 and, thirdly, as a fine light-coloured loam or loess. 

 But in all cases the organic remains for each district 

 are of the same order and in the same condition. 



The Surface Rubble and Head. In the south of 

 England this Drift commonly assumes the form of a 

 bed, varying in thickness from a few inches to a 

 few feet, of angular fragments of rock with loam, 

 derived from adjacent higher ground, and lying on 

 the slopes of the hills and at the bottom of the 

 valleys. It is frequently altogether absent, but where 

 there have been hollows in the original surface of the 

 underlying solid rocks this Drift has lodged there 

 in greater quantities, and occasionally attains a thick- 

 ness of 20 to 80 ft. or more. 



Previous to the deposition of this rubble the land 

 in this area stood several feet lower than at present, 

 and had been worn back by the sea so as to form a 

 Jine of old beach and cliffs (see Fig. 1, p. 22), which, 

 now that the land has been raised, stand 10 to 30 ft. 

 above the existing sea level, and in places extend 

 inland. 1 In the trough formed by the ledge of the 

 Raised Beach and the face of the old cliff, 2 the 

 rubble has often lodged in such large quantity as 

 to completely mask the old cliff, which would not be 



1 Quart. Journ. Geol. Soc. for 1892, map plate viii., and 

 Geology Chemical, Physical, and Stratigraj>hical, vol. ii. pp. 

 013, 614. 



2 On the Raised Beaches of the south of England, Quart. 

 Journ. Gkol Soc. for 1892, pp. 264-343. 



