It is in this accumulation of calcareous strata that numerous bones and teeth of the Mammoth, or fossil Elephant, have been discovered; I have therefore designated it, the Elephant-bed, to distinguish it from other loose calcareous deposits.
As seen immediately beyond Kemptown ([Lign. 267]), the cliffs appear to be entirely composed of the materials above described; but farther on, the face of the ancient chalk-cliff is exposed (see [Lign. 268]); and if we extend our walk to Rottingdean, we find in many places the Chalk alone forming the present cliff; the Elephant-bed and its associated shingle and sand having been swept away. A like destruction awaits the remainder of these interesting deposits at no very distant period.[791]
[791] See Foss. South D. p. 277, pl. iv.; and Geol. S. E. p. 30; Wond. p. 113.
After collecting specimens of the Elephant-bed, both of the friable varieties, and of the coombe-rock, and a few of the pebbles of granite, porphyry, &c. from the ancient beach, and also some of the sand beneath the shingle, to examine microscopically on our return home, let us sit down on this mass of fallen chalk, and consider the nature of those changes in the relative position of the land and sea, which the phenomena before us appear to indicate.
We have seen that these cliffs are composed of the following deposits:—1. The Elephant-bed ([Lign. 267] and 268, a); a series of calcareous strata, with bones and teeth of Elephants, Horses, Deer, and Oxen. 2. An ancient sea-beach (b), with pebbles and boulders of plutonic rocks, and bones of mammalia; and a bed of sand beneath, in which cetacea and mollusca (apparently of existing species) have been found. 3. Lastly, the regular Chalk-strata ([Lign. 268], c, c), extending far out to sea.
These appearances demonstrate the following sequence of physical changes, namely—
1stly. The Chalk terrace (c, c), on which the ancient shingle-bed (b) rests, was on a level with the sea for a long period; for this beach must have been formed, like the modern, by the action of the waves on the then existing chalk cliffs (see [Lign. 268], Chalk). But there must have been some cause in operation, by which pebbles and boulders of granite, porphyry, and other rocks, foreign to our shores, and bones of Elephants, &c. were thrown up on the strand, and imbedded in the beach then in the progress of formation. These transported materials may have been floated to the Sussex coast by icebergs; an agency by which the delicate bones and teeth might be deposited without injury, although surrounded by the water-worn detritus (see p. 43).
2dly. The whole line of coast, with the ancient shingle, must have subsided to such a depth, as to have allowed of the deposition of the calcareous strata, forming the Elephant-bed. And from the absence of gravel and beach, and the circumstance of the chalk-rubble, of which they are largely composed, often presenting angular fragments, it would appear that this deposition took place in some tranquil bay or inland sea.
Lastly. The land was elevated to its present level; and at this period the formation of the existing sea-beach and line of cliffs commenced.
The reader must not conclude, from our remarks being restricted to the cliffs before us, that the phenomena here contemplated were limited to this district; on the contrary, if our space would permit, it might be shown that they are referable to extensive geological changes, which took place in the period immediately antecedent to the present. In all the valleys of the South-east and East of England that open into the sea, traces, more or less extensive and important, of similar deposits exist. The level plain, called the Steyne, at Brighton, is entirely formed of the Elephant-bed, which extends up the valley to Preston and Patcham; in the latter place bones and teeth of Elephants have been found. At Southbourn, the plain at the foot of the Chalk hills, called "The Wish," containing remains of the Elephant, Rhinoceros, and Hippopotamus, evidently belongs to the same epoch. At Folkstone, Mr. H. Carr has discovered large blocks of Coombe-rock, and Mr. S. J. Mackie abundance of bones; and at Dover, above the Chalk, similar masses occur. On the opposite coast of Franco there are also indications of these deposits. All these phenomena are no doubt connected with the occurrence of immense quantities of mammalian remains in the superficial loam, &c. on the eastern coasts of England, and are referable to the same geological epoch.