Page:Transactions of the Geological Society, 1st series, vol. 2.djvu/194

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Mr. Webster on the Strata lying over the Chalk.
fruits and branches still to be observed in it. It sometimes splits into irregular layers in the direction of the bed, and the cross fracture is dull and earthy. It burns with difficulty, and with very little Same, giving out a sulphurous smell.
v, Yellow and white sand, with crimson and grey stripes.
w, Five beds of coal similar to that above-mentioned, each a foot thick.
x, Whitish sand and brownish pipe clay.
y, Whitish sand with stripes of deep yellow.
z, Several layers of large water-worn black flint pebbles, imbedded in deep yellow sand.
B, A stratum of blackish clay, with much green earth and septaria. In this green earth are a prodigious number of fossil shells, but in a very fragile state. They correspond exactly with those of Stubbington and Hordwell.

A stream of water from the adjoining hill has worn a deep channel through the stratum, and affords a path down to the bay.

To the north of this, the strata C consist of yellowish sand; and it is not easy to see what is really the position of those beds which lie immediately next to the blue clay, but they appear to dip about 45° to the north; and the sand D lying on them is nearly horizontal.

The north side of Alum bay is bounded by a hill called Headen, about 400 feet high, considerably loftier than the vertical cliffs, and composed of the same part of that series of horizontal strata of which the north side of the island consists. In this hill only do we distinctly see the alternation, I have mentioned of marine and fresh water deposits. It is in a state of constant ruin, and by its section affords lofty vertical cliffs, where its strata may be examined with the utmost facility.