Page:Transactions of the Geological Society, 1st series, vol. 4.djvu/305

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on the chalk. This chalk rises suddenly to a lofty cliff on the east side of the flat ground that lies between Newhaven and Seaford, dividing the beds of the plastic clay formation at Newhaven from their outlying fragment at Chimting, with which they probably were connected before the excavation of the valley of the Ouse.

The upper surface of the chalk at Chimting, as seen in the cliffs, dips at an angle of about 20° to the west. The dip of the incumbent beds of breccia and sand is conformable with it. These last beds are soon lost in ascending the hill eastward from the Castle; first the sand ceases, and afterwards the breccia having formed a thin cap on the chalk for a short distance disappears a little below the Signal House about one mile east of Seaford. Hence the chalk extends forming a cliff to Cuckmere Haven, where on the heights composed of it on the west of the Cuckmere river, we sought in vain for the stratified sand and breccia, finding nothing but an alluvial cap of sand and gravel; and as far as the eye could judge, looking eastward from this point, there was no appearance of superior beds on any summits of the chalk which forms the entire substance of those magnificent cliffs that extend from Cuckmere Haven to Beachy Head.

At Newhaven, in the lowest part of the Castle Hill close to the mouth of the Ouse on the west side, we again found the breccia that has been described at Chimting Castle, nearly of the same thickness and in the same state and relative position between the upper surface of the chalk and the incumbent beds of sand; it differs from it only in being less firmly cemented, and appears equally identical with the oyster bed at Reading. The greater number of its flints are not much rolled.

The state of the tide, and their elevated position, prevented us from examining the hollows on the surface of the chalk in which