154 



PROCEEDINGS OF THE GEOLOGICAL SOCIETY. 



recently afforded a section of part of the beds beneath the London 

 clay at that place. 



Trial bore at Chelmsford. 



(Specification paper.) 



Feet. 



TDark mould 3 



T)rirA YeUowclay 1 



^^Vi--\ Gravel 15 



tSand (dark) 51 



London \ b. \jonAon c\&y 100 



Clay. \a. Loudon clay and silver sand 50 



f Dark sand 12J- 



Clay-slate (?) 0| 



Clay and sand 4 



^ Clay-slate (?) 0^ 



Dark sand, with fine clay at intervals 9^ 



Clay, sand, and shells 2^ 



Clay and shells 0^ 



Pebbles H 



Sand (spring) 4-^ 



256 



As I have not had the opportunity of seeing the specimens, I am 

 unable to say positively to what part of the Lovper Tertiaries these 

 beds may belong : it is probable, however, that those beneath the 

 London Clay down to the " Pebbles " inclusive may belong to the 

 "Woolwich series, and that the " Sand (spring) " may be the top of 

 the Thanet Sands. The beds called "clay-slate" are, I presume, 

 hard laminated clay or shale. 



I have also recently been furnished by Mr, A. C. Veley of Bram- 

 tree with the followina; section of a well at Halsted. 



Woolwich 



and 

 Reading 



Well-section, White Hart, Halsted. 



(Letter from the Rev. W. Clements.) i' 



Feet. 



A layer of sand and gravel 7 



A bed of yellowish clay 8 



The London clay 89 



II. Woolwich I A layer of yellow sand passing into brovni clay ... 7 



and Read- \ A bed of plastic clay 19 



big Series. J A greenish sand 15 



III. Thanet J Several layers of sand gradually passing from a 



Sands. \ light colour to nearly a black, about 25 



Chalk 30 



About 200 



The Rev. W. B. Clarke also gives sections of two wells at Harwich, 

 in which the mottled clays appear, but no fossils. (Trans. Geol. Soc. 

 2ud ser. vol. v. pp. 369, 370.) 



