30 Mr. W. Whitaker on some Surrey Wells. 
149.—Some Surrey Wetts. (Third Paper.) 
By W. Wurraxer, B.A., F.R.S., V.-P.G.S., Assoc. Inst. C.E., 
F. San. Inst., Pres. Geol. Assoc. 
(Read December 18th, 1900.) 
My second paper, in our Transactions for 1894, 5, brought 
the total number of recorded well-sections in our county up to 
257. Now 45 are added, bringing the total to 302. Besides 
these, however, there are records of depth, water-level, &c., of 
many other wells, in papers by Mr. Latham, Mr. Lucas, and 
others, which would have to be noticed in any systematic account 
of the water-supply of Surrey. I have noticed only wells with 
some geologic bearing, and, owing to the length of this paper, 
some in distant parts of tlhe county are kept back. 
The wells now to be noticed are, with few exceptions, divisible 
into two groups: those in which the Lower Greensand is the 
source of supply aimed at (5), and the much greater number (38) 
in which the Chalk is the object. Besides these, there is one 
well in Tertiary beds, and one in gravel. 
Of these wells, only one, at Kingston, is more than 500 feet 
deep (615 feet). Only one, on the other hand, is under 100 feet. 
As regards the thickness of the geologic formations passed 
through, the greatest amount of the Drift, with other superficial 
beds, is only 84 feet, at Southwark. The London Clay is 
nowhere passed through, from top to bottom; but 300 feet of it 
has been found in one case, at Raynes Park, Merton. The 
thickness of the Lower London Tertiaries, where proved from top 
to bottom, varies from 57 feet at Streatham to 119 at Croydon ; 
and of the three members of the Series, the uppermost (Black- 
heath and Oldhaven Beds) is rarely found, the middle (Woolwich 
and Reading Beds, in one condition or another) and the lowest 
(Thanet Sand) are always present. The greatest depth in Chalk 
recorded is 858 feet (much less than the total thickness). Of 
the Upper Greensand we learn absolutely, and of the Gault 
practically, nothing. Of the Lower Greensand, a thickness. of 
250 feet has been proved at Oxted; but the uppermost division 
(Folkestone Beds) has nowhere been pierced from top to bottom: 
the next underlying division (Sandgate Beds) is 38 feet thick at 
Godstone, decreasing to 30 at Oxted, and 11 at Limpsfield: of 
the Hythe Beds, a thickness of 152 feet has been recorded at 
Oxted. 
Where not otherwise stated, the figures stand for feet. Words 
in square brackets have been added by the writer. 
