902 J. PKESTWICH OX THE RANGE OF THE LOWEK 



52. On the Section of Messes. Metjx & Co.'s Artesian Well in the 

 Tottenham-Court Road, ivith Notices of the Well at Cross- 

 ness, and of another at Shoreham, Kent ; and on the probable 

 Range of the Lower Greensand and Palaeozoic Rocks under 

 London. By Professor J. Prestwich, M.A., F.R.S., F.G.S., &c. 



In 1851* I expressed an opinion that, as the Upper and Lower 

 Greensands, with the intermediate Gault, cropped out from beneath 

 the Chalk both on the north and south of London, the same strata, 

 in all probability, passed beneath the chalk-basin without break, and 

 that the Lower Greensand might be found available as an additional 

 source of water supply to London. The boring made shortly after- 

 wards at Kentish Townf by MM. Degousee and Laurent, of Paris, 

 showed, on the contrary, that while the Upper Greensand and the 

 Gault were prolonged as expected, the Lower Greensand was absent, 

 and was replaced, at a depth of 1114 feet, by strata of hard mica- 

 ceous red and variegated fine-grained sandstones and clays. These 

 were traversed for a thickness of 188 feet, when the work was 

 abandoned. 



In the absence of fossils, and the confusion produced by the intro- 

 duction from above of debris and extraneous fossils from the Gault 

 and Upper Greensand, much uncertainty prevailed for a time with 

 regard to the age of these sandstones, which were considered by 

 some as modified forms of the Lower Greensand or the Wealden, 

 and were referred by others to Permian or Triassic strata. Prom a 

 subsequent examination of the Old Red Sandstone in the neighbour- 

 hood of Prome, I came to the conclusion that they belonged to strata 

 of that age J, as I found the Kentish-Town specimens agreed closely 

 with the Mendip beds in lithological characters, whereas there was, 

 on the whole, a want of agreement with the Permian or Triassic 

 series. I was confirmed in this view after seeing the Red Sand- 

 stones and Marls, belonging to the Devonian series, which crop out 

 from beneath the Coal-measures in the neighbourhood of Mons in 

 Belgium. 



Still, owing to the absence of fossils, an uncertainty existed on 

 the subject, which has now been effectually removed by the recent 

 boring at Messrs. Meux & Co.'s brewery. This well-known brewery 

 is situated at the south end of the Tottenham Court Road, at its 

 junction with Oxford Street. The original well was sunk many 

 years ago, and carried into the Chalk to a depth of 365 feet. In 



* See ' The Water-bearing Strata around London,' by the author. Van Voorst, 

 1851. 



t Quart. Journ. Geol, Soc. vol. xii. p. 6, 1856. 



X Eeport of Royal Coal Commission of 1869, vol. i. p. 161 ; Anniversary 

 Address to the Geological Society for 1872 ; and Min. of Proc. Civil Engineers, 

 vol. xxxvii. p. 14 (1874). 



