Ferruginous flint gravel interstratified with sand—18 feet. Light blue marl in the upper part running into sand—12 feet. Ligneous bed—12 inches. Bluish marl running into shades of light grey, caused by the comminuted shelly matter—15 feet. Ligneous bed—9 inches. Green marl—3 feet 6 inches. Limestone—4 inches. Lignite—1 inch. Green marl—5 feet 4 inches. Grey sand—portion of Dr. Wright’s Crocodile Bed—4 feet. Fossil bed—9 to 13 inches. a, b—Bands of tough brown clay, not continuous. c—Coprolite bed appearing here and there, and always full of organic remains. Sand bed, uncertain—1 foot 8 inches. Light blue marl—4 feet 6 inches. Grey sand—2 feet 5 inches. Leaf bed, which here rises from the beach—18 inches. The present sea-shore.
It is a bed, however, which is seldom open, and can be worked only at particular tides. It may easily be recognized as lying between the Leaf Bed and the well-marked Lignite Bed, which shows the first traces of salt-water, and where, in the lower portion, Neritina concava may be abundantly found. This last bed may be well seen at Beckton Bunny (Section II.). The lignite, however, though it will give a good deal of heat, will not blaze. Locally it is sometimes used for making black paint.
Section II. of Beckton Cliff immediately to the west of the Bunny.
Flint gravel—scarcely more than 3 or 4 feet, with an uncertain band of white sand. Lignite—3 inches. Brown clay—3 inches. Lignite—3 inches. Marl and sand—2 feet 2 inches. Ligneous bed, containing shells much broken—8 inches. Grey sand—2 feet 4 inches. Orange-coloured sand, with very few fossils at this point, though plenty eastward—15 feet 9 inches. Olive bed. Fossils abundant—27 feet 3 inches. The present sea-shore.
Passing on to Beckton Bunny we reach the first true bed of the Lower Marine Formation, which rises a little eastward of that ravine. I have distinguished it as the Olive Bed, from the abundance of specimens of Oliva Branderi, forming the equivalent to number eighteen in Dr. Wright’s arrangement, and which, when worked, emits a strong smell of sulphur.
Immediately under the Olive Bed, as seen in the opposite section (II.), taken immediately on the west side of the Bunny, rises grey sand, seventeen feet and a half in thickness, possessing only a few casts of shells. The next bed, however, composed also of grey sand, rising about three hundred yards farther on, is, perhaps, the richest in the whole of this Marine series, and its shells the best preserved. It may at once be recognized by the profusion of Chama squamosa, from which it has been called the Chama Bed. Specimens of Arca Branderi and Solen gracilis may be found here as perfect as on the day they were deposited.
A little farther on, nearly under the Gangway, rises the Barton clay, encrusted with Crassatella sulcata.[272] And here, on looking at the cliff, we may notice how all the beds, as they rise westward, gradually lose their clayey character, and run into sand, which will account for this part of the cliff foundering so fast. The water percolates through the sand down to the Barton Beds, and the loose mass above is thus launched into the sea.
Below the Barton Coastguard Station rises another bed of green clay, containing sharks’ teeth and the bones of fish. About a mile farther on, the High Cliff Beds emerge rich with Cassis ambigua and Cassidaria nodosa. And below them, seen in the channel of the stream flowing through Chewton Bunny, rises a bed of bright metallic-looking, green clay, the Nummulina Prestwichiana Bed of Mr. Fisher, containing sharks’ teeth and some few shells. Beyond, a little to the west of High Cliff Castle, occurs the well-marked Pebble Bed, the commencement of the Bracklesham Series, containing rolled chalk flints, and casts of shells. Next follow grey sands full of fossil wood and vegetable matter, marked by a course of oxydized ironstone-septaria. Then succeeds another Pebble Bed, and lastly appear the grey Bracklesham Sands.[273]
We have thus gone through the principal beds, both of the Freshwater and Marine Series, as far as they are exposed in this section along the sea-coast. The fluvio-marine beds stretch away eastward as far as Beaulieu and Hythe, but their clays here contain very few shells. On the other hand, the Bracklesham Beds trend away northward towards Stoney-Cross, appearing in the valley, and cropping out again on the other side of the Southampton Water.