266 



J. E. Marr — Glacial Deposits. 



(Fig. 3). The pit here is mainly cut in the ferruginous sands of the- 

 Crag, which show a total thickness of 30 feet here, without any 

 signs of approaching the base. The beds are quite like those of the 

 Crag ridge in Mr. Green's pit, save that they are here markedly 

 false-bedded. The surface is perfectly even except in one place, 

 where a rounded ridge rises up five feet above the surface of the 

 surrounding sand (C^ Fig. 3). The Crag is succeeded here by 

 Boulder-clay, which is at the top an ordinary blue laminated 

 Boulder-clay, with the usual scratched chalk boulders, as well as 

 others of flint, oolitic limestones, sandstones, etc., and below this 

 two feet of a sandy laminated Boulder-clay, of a reddish colour, the 

 sand being evidently derived from the underlying Crag. 

 Fig. 3.— Pit on Balingdon Hill. 



C. False-bedded sands, ferruginous above, bleached at base, 25 feet seen \ Eed 

 C". Ditto bleached, projecting into drift, 5 ft. J Crag. 



1. Sandy laminated Boulder-clay, 2 ft. 

 1'. Blue laminated Boulder-clay, to 10 ft. 



The last section I shall notice is in Mr. Allen's pit, close to the 



river-side, and about half a mile south-east of the last-mentioned 



exposure. This appears to be the pit described by Mr. Whitaker as 



the ' Grove.' It is of interest as showing two Boulder-clays (cf. 



Fig. 4.— S. end of Mr. Allen's Pit, Sudbury. 



1. Lower Boulder-clay, 20 ft. seen. 3. Loam, to 15 ft. 



2. Sand and gravel, 10-12 ft. 4. Upper Boulder-clay, to 16 ft. 



Fig. 4). The lower one is a leaden-blue clay, often very dark, 

 laminated, and with many chalk boulders, twenty feet being seen, 

 and Mr. Allen informed me that below it a hard sandy rock occurred 

 with a band of round pebbles below, almost immediately underlain 

 by the Chalk. The hard sandy rock and pebble bed are most 

 probably the beds of the Crag which are seen at the bottom of the 

 ridge in Mr. Green's pit. It will be noticed that the base of the 

 drift is here about 150 feet below its position on Balingdon Hill. 



The Lower Boulder-clay is succeeded by sand and gravel, altogether 

 like that of Mr. Green's pit, so that description is unnecessary. 

 The same may be said of the succeeding loam, which is here rather 

 more sandy than on the left bank of the Stour. 



