132 



PROF. J. PRESTWICH ON THE RELATION OF THE 



Fig. 7. — North end of the Raihuay Section hetween 

 Chaijl a 7 M J J / (1849). 





feet 



b. Bluish-grey Boulder-clay 12 



b'. Coai'se ferruginous gravel 2 



c. Stratified sands and shingle, yellow and bright ferruginous ochreous 



(Westleton) 6 



/. London Clay. 



No fossils were found in any of the sections, except in some 

 Post-Glacial Beds at Sudbury and Lamarsh. 



Similar sands and shingle have apparently a considerable develop- 

 ment in North Essex ; but they are generally hidden by Boulder- 

 clay, or masked by Glacial gravel, which, when fine and stratified, 

 they resemble in general appearance, and sometimes assimilate to it 

 in composition, owing to an admixture of the two beds. On a hill 

 1| mile north of Coggleshall there was a section showing 4 feet of 

 Glacial gravel overlying 6 feet of bright yellow and ochreous sand 

 with flint- and white quartz-pebbles (Westleton). 



The Witham and Braintree branch line likewise exhibited some 

 very illustrative sections of the Glacial and Westleton Beds (figs. 8, 9). 



Fig. 8. — Section on the Hailwai/, one mile north of Witham. 



h 1 



/ 



a. Brick-earth. 1 -r, , ^, . , 

 a\ Flint-gravel. \ P«st-Glacial. 



b. Chalky Boulder-clay. 



c. White sand with shingle at base (Westleton). 

 /. London Clay. 



The shingle consisted of — 



per cent. 



1. Flint-pebbles 32 



2. White quartz-pebbles 24 



3. Subangular fragments of flint 35 



4. Subangular fragments of chert and ragstone 9 



100 



