452 PROCEEDINGS OF THE GEOLOGICAL SOCIETY. [June 19, 



mid-terrace gravel below. These strips of London Clay are seen 

 at Hanwell, at Acton, and for upwards of three miles from Ken- 

 sington to Temple Bar, always at an average level of 50 feet*. 

 Along the sides of all the tributary streams, the Brent, the Acton 

 stream, and the Serpentine, this strip of the London Clay is also 

 found at about the same general level of 50 feet, dividing the high- 

 terrace gravel into patches. The lower margin of the mid-terrace 

 gravel runs from the river at Kew, by Chiswick House to Chiswick, 

 where it again joins the river ; all below this line, in the bend of the 

 river, is the thii-d, or low-terrace. In the next bend of the river to 

 the eastward, the margin of the mid-terrace is not so well defined ; 

 but Mr. Whitaker has traced it along the river below Hammer- 

 smith to Fulham Church, and thence to Sandy End and Walham 

 Green, and to the river at Cremorne. South of the river we have 

 low-terrace at Ham, Petersham, Richmond, Kew, East Sheen, Barnes, 

 Putney, "Wandsworth, and Battersea. The mid-terrace is wanting, 

 except between Barnes and Putney, to the north of the Barnes stream. 

 A line of high-terrace gravel runs from Eichmond Hill to East Sheen, 

 commencing at the height of 50 feet. At Roehampton and Putney 

 Heath, the high-terrace, if it be high-terrace, runs no lower than 

 the 100-feet line, and rises to the height of 170 feet on Putney 

 Heath. On Wandsworth and Clapham Commons the gravel rises to 

 the height of 100 feet ; this Clapham and Wandsworth gravel Mr. 

 Prestwich formerly regarded as high-level, and considered it to form 

 the same plain with that of Putney Heath. But both Mr. Prestwich 

 and Mr. Whitaker, I beheve, now consider the Wandsworth and 

 Clapham to be high-terrace gravel, whilst that of Putney Heath and 

 Wimbledon Common may be high-level gravel or a higher terrace of 

 the river-gravel ; certainly, if the level is to be taken as the criterion 

 of classification, the Clapham and Wandsworth gravels would appear 

 to correspond with the high-terrace gravel on the north side of the 

 river, and to be somewhat lower than that of Wimbledon Common. 

 As on the north, so on the south side of the river, the high-terrace 

 gravels are divided from the mid- or low-terrace gravels by strips of 

 the London Clay throughout nearly the whole of this district. Above 

 Ham and Petersham the strip rises to a considerable height in Rich- 

 mond Park. From Richmond to East Sheen, the upper margin of 

 the strip, and the commencement of the high-terrace gravel, judging 

 by Mr. Mylne's map, appears to be on the 50-feet line, whilst the 

 mid-terrace gravel ends in about the 30-feet line. On the Roe- 

 hampton and Putney-Heath hills the mid-terrace rises to the 60 -feet 

 Hne, while the upper-terrace gravel commences at about 100 feet, 

 leaving the space between the 50- and 100-feet lines occupied by the 

 strip of the London Clayf. 



It seems to be doubtful whether or not this strip of clay runs along 



* It is very probable that this strip will eventually he found to run further 

 south along the valley of the Brent, and along the 50-feet line by Little Ealing, 

 to join the strip at Acton ; but this cannot now be determined. — A. L. F. 



t This description is taken from Mr. Mylne's Map, which I have not had an 

 opportunity of verifying in this place. 



