434 Mr PHEAR, ON THE GEOLOGY OF SOME PARTS OF SUFFOLK, 



At the bottom of one of these bluffs Fig. (4). 



{say at A, fig. (4)}, just above Bramford 

 paper-mill, is a small chalk-pit, where a thin 

 stratum of London clay seems to rest im- 

 mediately upon the chalk, itself being over- 

 laid by sand and fine laminated clays ; but , 

 this section is too small and obscure to be 

 worth much. What is the constitution of 

 the rising ground to the back I have found no opportunity of ascertaining. 



From Claydon to the opening of the Coddenham valley the sand-cliffs are concealed by 

 the plantations and gardens of Shrubland ; a pit is worked in them for economical purposes, 

 and is said to exhibit a section of at least forty or fifty feet of pure red and white sand resting 

 on the chalk. At this point the tongue between the Gipping and its Coddenham branch is 

 very narrow, and is formed entirely of this sand with its chalk foundation. 



Throughout the whole length of the Coddenham valley until it dies away just beyond 

 Hemingston Hall, the sand-cliffs form a very decided feature, especially on the north side ; 

 they generally shew themselves in the shape of rabbit-warrens or plantations: the hollow 

 running up from Coddenham limekilns to Coddenham Row is a very good and picturesque 

 example of their form. There is but little opportunity for examining their structure, and I 

 have only seen the small section afforded by a pit exactly opposite Hemingston Hall : fig. (5) 

 represents it : pj„ r^\ 



(1) Irregular gravel containing portions of gryphea, laminae of 1 



Inoceramus (?) and other traces of worn drift. '//////*///'///// 



(2) Irregular layers of sand (full of small chalk-stones) and 

 small pebbles. 



(3) Pure white sand, the bottom of which is not seen. 



The surrounding country rises very slowly and almost imperceptibly from the top of these 



cliffs, but at a very short distance from their edge the soil passes into most unmistakeable 

 drift-clay. In the annexed transverse section of the valley the figures refer to the superficial 

 phenomena. J!___ _____ Fjg ( 6) 



(1) Pure white sand. 



» G ""'- 'l/i/7J777mTTTTTTf7F////////i 



(3) Drift-clay. chalk 



In a lateral depression at Hemingston (marked Dunstans on the Ordnance map) is a 

 brickfield worked in a layer of pure grey clay, stratified and full of small chalk pebbles, about 

 five feet thick: this bason is lower than the sand-cliffs, but not so low as the bottom of the 

 valley : the workmen represent its floor to be a coarse chalky clay (probably chalk-rubble), 

 and speak of some " joint-bones" being sometimes found there in groups. 



At Bridge Place, where the Ipswich and Norwich turnpike-road crosses the mouth of the 

 Coddenham valley, on the left ascending Creeting hill, is a large deep chalk-pit, in the side of 

 which towards the valley is an irregular opening of considerable size, stopped up by a mass 



