Page:Quarterly Journal of the Geological Society of London, vol. 27.djvu/401

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described by successive authors is marked by the vertical lines on the right of the following account, except for the irregular cap of gravel, which appears in all but the earliest.

1. Coarse red gravel, mostly of subangular flints, but also with flint pebbles, rather clayey, 10 feet or more.

2. London Clay.

Grey and brown clay, sometimes 10 feet or more, 3 feet. yielding water Fine buff sand, passing into and causing Brown and grey loam, passing into slips. Thinly bedded grey and brown clay, a few feet.

Basement-bed : flint-pebbles of moderate size in clay and ferruginous sand, about a foot.

4. Roughly laminated bluish-grey clay (like London Clay) about 4-1/2 feet (8 feet in Mr. Prestwich's section).

Oyster-bed, rather hard, clayey, a foot to 2 feet or more (5 feet in the earlier account). Shelly clays, 2 feet or more. Grey and brown clay, partly sandy, often with a bed of shells in the middle. 2-1/2 feet? Light-coloured sand, partly pink, with thin layers of clay and traces of vegetable matter, yielding water and causing slips, about 6 feet, passing into Grey laminated clay with a few layers of shells, at one part a thin bed of ironstone with casts of shells, about 8 feet ? Shelly clay, a few feet. Clay, with shells at bottom, about 2 feet, below which there is generally A hard layer, in great part iron-pyrites ? an inch or more. Hard dark sand or clay, a few inches. Thin peaty bed. (These three thin beds vary ; sometimes the hard layer is absent, sometimes the lignite.) 7. Pale grey and brown clay, partly lilac-coloured, and with large pieces of selenite, 6 feet or more. 8. Light-coloured sand, mostly of a pale yellowish- green tint. At one part a bright-red mottled bed near the top. In the middle a brown and apparently harder bed, which projects (not accessible).

9. Bottom bed, green-coated and iron-stained flints in greensand, about 2 feet. It is from this bed (or from a local clayey layer at its base) that the Websterite has come. It rests evenly on

10. Chalk with flints.

The beds seem to vary both in thickness and structure, which accounts for the slight differences in the various descriptions. The top of this small but interesting outlier is crowned by a Bri-

  • Quart. Journ. Geol. Soc. vol. x. p. 83.

† Trans. Geol. Soc. (Ser. i.) vol. iv. p. 296.

‡ The Fossils of the South Downs, or Illustrations of the Geology of Sussex (4to, Lond.), p. 257.

§ The Geology of the South-east of England (8vo, Lond.), p. 54. Merely a shorter reprint of the former as regards this section.

|| Trans. Geol. Soc. (Ser. i.) vol. ii. p. 191.