Siirreif Wrlls and their Te/ichifUfs. 57 



Maiden. — Mosthi (/ Mo.<;jier) Farm, Mr. Blake's. 1865. 



Sunk aud communicated by Messrs. S. F. Baker & Sons. 

 Water within i feet of the ground. 



Clay (? Bhio clay 228 feet, then plastic clay) 304 



Sand (full of water) 6 



Coloured [mottled plastic] clay, not bottomed 4 



Merton. — Sewerage Works {Croydon Rural Sanitary Authority), 

 north of Wandlebank House. ? 1879. 



Communicated by Mr. W. S. Crimp. 



36 feet above Ordnance Datum. 



Bored throughout (6 inches diameter). 



Water overflows at the rate of about 40,000 gallons a day 

 (recorded as over 52,000 in Proc. Assoc. Municipal and Sanitary 

 Engineers for 1879, p. 21), at a temperature of about 54°. 



Alluvium 10 



Ballast [River Gravel] 1^ 



London Clay 51 



'Shells 1 



Brown sand 5 



Blue clay and shells 7 



SheUs U 



Dark clay 8 



Blue clay 3 



[Woolwich and Black clay 3 



Reading Beds, -I Yellow clay 3 



62.Jft.-l Piu-ple clay 3 



Red clay 4 



Brown and green sand 1^ 



Brown sand 9^ 



Brown clay 5 



Pebbles U 



.Green sand 6^ 



Grey [Thanet Sand] 39^ 



To Chalk 184^ 



Mitcham, — CoUiersivood. 



Communicated by Mr. W. S. Crimp. 

 52i feet above Ordnance Datum. 



* I am in doubt as to referring the whole of this to this series. In the 

 abstract account in the Proc. Assoc. Municipal Engineers (and ' Iron,' vol. xv., 

 no. 36G, p. 44, 1880) the thickness of the formations differ, London Clay being 

 given as SO feet, Woolwich Beds as 40, and Thanet Sand as 47, the depth 

 to theChalk being 17'J, and in Chalk 51. 



