Page:Quarterly Journal of the Geological Society of London, vol. 26.djvu/731

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1870.]
CODRINGTON—HAMPSHIRE AND ISLE-OF-WIGHT GRAVELS.
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inland to Wimborne, Downton, Bramshaw, Romsey, and Bishopstoke; it also includes the Isle of Wight.

Tertiary formations occupy the whole of the area, with the exceptionof the southern part of the Isle of Wight; and the surface is very generally covered with superficial deposits, which are the immediate subject of this paper.

The rivers Frome, and Trent or Piddle, enter Poole harbour on the west, and the Stour, Avon, Test, Itchen, Hamble, and Titchfield rivers flow through the district. All these rivers, as well as the Medina, Tar, and Brading rivers, in the Isle of Wight, rise in the chalk, or in beds not much below it, and after draining a considerable extent of chalk-country, pass through the Tertiary area to the sea. The Avon water, Boldre, and Exe or Beaulieu river, rise among the Tertiary beds of the New Forest, of which they drain the larger portion.

Among those by whom the superficial deposits of the district have been noticed, are Sir C. Lyell, Messrs. Webster, Prestwich, Trimmer, E. Forbes, Godwin-Austen, Bristow, Evans, &c. Of late years, the discovery of numerous flint implements along the coast between Southampton Water and Gosport, near Bournemouth, and more recently near Southampton, and near Lymington, has given a fresh interest to the gravel from which they are derived; and the publication of the new Ordnance Maps with levels over a large part of the district, has facilitated the construction of many accurate sections of the surface. For the western part of the district, where the new Ordnance Survey is unfinished, levels have been supplied me by permission of Sir H. James, from which, and from other sources, as well as from personal observation, the sections have been extended in that direction.

The sections (figs. 1 to 10, Pl. XXXVII.) are selected from many others constructed; they are drawn to a scale of two miles to an inch horizontal, and 800 feet to an inch vertical. The heights in feet above the mean level of the sea are figured at numerous points, and the position of the lines of section are shown upon the map (Pl. XXXVI.).

II. The mainland of Hampshire.

(a) The physical features of the country, and its superficial deposits, are so closely connected that they must be considered together. The New Forest, and the neighbouring country between Poole and Southampton Water, is characterized by high level plains, very generally covered with gravel or brick-earth. On closer examination, these plains are found to be portions of a tableland with a very gradual southern slope, through which the larger rivers flow in well-defined valleys, and which has been a good deal cut up and over large areas entirely removed by the action of the tributary streams flowing in what arc locally called the " bottoms."

Section No. 1, from Fordingbridge and Breamore to Bramshaw, and No. 2, from Poole to Southampton Water, which are nearly