Yol. 62.] THE CLAY-WITH-FLINTS. 151 



the tracts of Clay-with-Flints continually descending to lower levels 

 as they are followed southwards. This is the case : in the northern 

 part of the area the Clay-with-Flints is only found on the summit 

 of ridges that rise to 700 or 800 feet, but in passing southwards, and 

 especially from north-west to south-east, we find it descending 

 gradually to about 300 feet. Thus, on Tidcombe Down in the north- 

 west the Clay-with-Flints sets in at a height of about 830 feet, and 

 there are several large tracts of it to the south-east, the boundary- 

 lines of which gradually slope from 700 to less than 400 feet, and 

 east of Andover it occurs on the Marsupites-chBlls. at a level of 

 300 feet. 



In this connection it is especially interesting to find that, in all 

 the larger tracts, Clay-with-Flints is associated with, and often 

 covered by, thick masses of brickearth and sandy mottled clays 

 which have evidently been derived from the destruction of the 

 Beading Beds. Further, in Harewood Forest, east of Andover, 

 patches of clean mottled clay and yellow sand occur, which were 

 originally described as outliers of Eeading Beds l ; but, on the more 

 recent map issued in 1898, they are included in the ' Clay-with- 

 Flints and Loam.' 



From the description given in the memoir above cited, it would 

 seem that masses of little-altered Eeading Beds do occur here at 

 the low level of 300 feet : thus confirming the suggestion above 

 made, that the Andover Chalk lies in a post-Eocene syncline, for 

 these remnants cannot be far removed from the position that they 

 occupied when in situ. It is also stated that some of the adjacent 

 material resting upon the Chalk is a reddish-brown mottled clay 

 containing pebbles, and having a layer of large black-coated flints at 

 its base : the whole being overlain by a gravelly deposit, consisting 

 of rounded and angular flints in a matrix of reddish-brown clay. 

 We seem to have here all the materials for making the mixture 

 usually known as ' Clay-with-Flints', and I cannot help thinking 

 that we are here provided with an illustration of a phase in the 

 making of Clay-with-Flints ; with a case, in fact, in which further 

 developments were arrested, owing to some local conditions which 

 may or may not be discernible by a more complete study of the 

 district. 



Close to the northern edge of the area in Sheet 283, and near 

 "Woodhay Clumps, is a small but instructive outlier of Eeading 

 Beds which touches the contour of 900 feet, and is only about 

 180 feet above the neighbouring outcrop of the Chalk-Eock. Hence, 

 though solution of the Chalk may have caused it to subside or slip 

 considerably below its original level, its position seems to indicate 

 that the thickness of chalk removed from this locality before the 

 time of the Eeading Beds was greater than usual. The Eocene 

 outlier is surrounded by Clay-with-Flints, which extends along 

 the southward prolongation of the ridge, its basal boundary passing 

 gradually from 900 to 650 feet. Other tracts on the south-east 



1 See ' Geology of Parts of Berks & Hants' Expl. of Sheet 12, Mem. Geol. 

 Surv. 1862, p. 28. 



