29 



between Duxford Grange and Ickleton, which is not more than 

 200 feet above sea-level, while the scarp two miles to the south- 

 ward must be nearly 450 feet high. The spur which runs east- 

 ward by Littlebury Green descends considerably towards the 

 valley of the Cam, and farther south the Boulder Clay runs 

 down quite into the valley by Wenden and Ne^\^^ort. It is thus 

 shown that the chalk escarpment and the Cam valley were 

 both in existence before the deposition of the Upper Glacial 

 Clay. 



The river Cam, rising among the drift-covered slopes 

 between Quendon and Thaxted, runs at first south-westward, 

 but turning northward by the former village, has cut for itself a 

 valley of some depth through the hills by New^Dort and Wenden; 

 in this valley several good sections of the Glacial beds may 

 be seen. 



Gravel and Sand underlying Boulder Clay and consequently 

 taken to be Middle Drift, may be seen in a pit just South of 

 London Wood opposite Quendon, and that village itself is pro- 

 bably built upon deposits of the same age. 



A section about three quarters of a mile E. of Newport 

 showed 16 feet of gravel and sand overlaid by 18 feet of Boulder 

 Clay, the latter rolling over the gravel towards the valley. 



At Wicken Bennett, 1| miles W. of Newport and situated 

 in a tribvitary valley, there is a large pit near the Church ; this 

 exhibits about 30 feet of coarse gravel wdth occasional inter- 

 bedded seams of fine sand and loam. The gravel is almost 

 entirely composed of flints, mostly unworn, some of them 

 being large nodular lumps as perfect as those in a chalk pit, 

 only stained brown with iron ^ large lumps of Hertfordshire con- 

 glomerate also appeared to be common, and the material would 

 seem to have been almost entirely derived from the destruction 

 of Chalk and Tertiaries. The hill above is capped with Boulder 

 Clay which rests on chalk both eastward and westward of the 

 village, so that the gravel is only a lenticular mass at the bottom 

 of the clay, and exposed in the valley. 



The gravels which flank the river near Newport and Wenden 

 are probably river deposits, though being to a large extent 

 derived from the Glacial Gravels, they greatly simulate them in 

 appearance : there is nothing in this neighbourhood which can 



