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Rh to observe the provisions, and the dispute was eventually referred to the arbitration of Louis IX. of France, who formally annulled them on the 23rd of January 1264, but expressly declared that his decision was not to invalidate the privileges, liberties and laudable customs of the realm of England, which had existed before the time of the provisions.

 OXFORDIAN, in geology, the name given to a series of strata in the middle Oolites which occur between the Corallian beds and the Cornbrash; the division is now taken to include the Oxford Clay with the underlying (q.v.). The argillaceous beds were called “Clunch Clay and Shale” by William Smith (1815–1816); in 1818 W. Buckland described them under the unwieldy title “Oxford, Forest or Fen Clay.” The term Oxfordian was introduced by d’Orbigny in 1844. The name is derived from the English county of Oxford, where the beds are well developed, but they crop out almost continuously from Dorsetshire to the coast of Yorkshire, generally forming low, broad valleys. They are well exposed at Weymouth, Oxford, Bedford, Peterborough, and in the cliffs at Scarborough, Red Cliff and Gristhorpe Bay. Rocks of this age are found also in Uig and Skye.

The Oxford Clay is usually bluish or greenish-grey in colour, weathering brown or yellow; in the lower portions it is somewhat more shaly. The beds frequently tend to be calcareous and bituminous, while in places there is a considerable amount of lignite. Septaria of large size are common, they have been cut and polisher at Radipole and Melbury Osmund in Dorsetshire, where they are known as Melbury marble or “turtle-stones”; they were used to form table-tops, &c. In Yorkshire the Oxford Clay is usually a grey sandy shale. In the central and southern English counties the Oxford Clay is divisible as follows:—

The upper zone contains also Gryphaea dilatata (large forms), Serpula vertebral is, Belemnites hastatus, Aspidoceras perarmatum, Cardioceras vertebrate. The lower zone yields Reineckia anreps, Peltoceras athleta, Quenstedtoceras Marine, Cosmoceras Jason, Cerithiiim muricatum, and a small form of Gryphaea dilatata. The remains of fishes and saurian reptiles have been found. The Oxford Clay is dug for brick-making at Weymouth, Trowbridge, Chippenham, Oxford, Bedford, Peterborough and Fletton.

The “Oxfordian” of the continent of Europe is divided according to A. de Lapparent into an upper (Argovian) and a lower (Neuvizyen) substage. In the former he includes part of the English Coralline Oolite and in the latter the lower Calcareous Grit, while a portion of the lower Oxford Clay is placed in the Divesian or upper substage of the Callovian. In north-west Germany the Oxford Clay is represented by the Hersumer beds. Most of the European formations on this horizon are clays and marls with occasional limestone and ironstone beds.

See, ,.

 OXFORDSHIRE (or Oxon), an inland county of England, bounded N.E. by Northamptonshire, N.W. by Warwickshire, W. by Gloucestershire, S.S.W. and S.E. by Berkshire, and E. by Buckinghamshire; area 755.7 sq. m. The county lies almost wholly in the basin of the upper Thames. This river forms its southern boundary for 71 m., from Kelmscot near Lechlade (Gloucestershire) to Remenham below Henley-on-Thames, excepting for very short distances at two points near Oxford. The main stream is the boundary line, but from Oxford upward the river often sends out branches through the flat water meadows. The principal tributaries joining the Thames on the Oxfordshire side do not in any case rise within the county, but have the greater part of their courses through it.

These tributaries are as follows, pursuing the main river downwards, (i) The Windrush, rising in Gloucestershire, follows a narrow and pleasant valley as far as Witney, after which it meanders in several branches through rich flat country, to join the Thames at Newbridge. (2) The Evenlode, also rising in Gloucestershire, forms the western county boundary for a short distance, and follows

a similar but more beautiful valley to the Thames below Eynsham. From the north it receives the Glyme, which joins it on the confines of Blenheim Park, where the woodland scenery is of peculiar richness. (3) The Cherwell, rising in Northamptonshire, forms some 10 m. of the eastern boundary, and with a straight southerly course joins the Thames at Oxford. From the east it receives the Ray, which drains the flat tract of Ot Moor. (4) The Thame, rising in Buckinghamshire, runs south-west and west, forming 6 m. of the eastern boundary, after which it turns south tf) join the Thames near Dorchester. Above the point of junction the Thames is often called the Isis. Lastly, a small part of the north-eastern boundary is formed by the Great Ouse (which discharges into the North Sea), here a very slight stream, some of whose head-feeders rise within Oxfordshire.

The low hills which lie south of the Windrush, and those between it and the Evenlode (which attain a greater height) are foothills of the Cotteswold range, the greater part of which lies in Gloucestershire. Between the Windrush and Evenlode they are clothed with the remaining woods of Wychwood Forest, one of the ancient forests of England, which was a royal preserve from the time of John, and was disafforested in 1862. Its extent was 3735 acres of forest proper. The hills continued north of the Evenlode (but not under the name of Cotteswold) at an average elevation over 500 ft. The range terminates at Edge Hill, just outside the county in Warwickshire. The hills bordering the Cherwell basin on the east are of slight elevation, until, running east from Oxford into Buckinghamshire, a considerable line of heights is found north of the Thame valley, reaching 560 ft. in Shotover hill, overlooking Oxford. Across the south-east of the county stretches the bold line of the Chiltern Hills, running N.E. and S.W. On the western brow, Nettlebed Common, an extensive plateau, reaches a, t some points nearly 700 ft. of altitude. The district was probably once covered with forest, and there are still many fine beeches, oaks and ash trees. William Camden in his survey of the British Isles (1586) mentions forests as a particular feature of Oxfordshire scenery, and there are traces still left of natural woodland in various parts of the lower country.

The Thames flows through a deep gap from about Goring downwards, between the Chilterns and the Berkshire Downs. Here, as above at Nuneham and other points, the sylvan scenery is fine, and Henley and Goring are favourite riverside resorts on the Oxfordshire shore. The western feeders of the Thames and Cherwell have much rich woodland in their narrow valleys, and the sequestered village of Great Tew, on a tributary of the Cherwell river, may be singled out as having a situation of exceptional beauty.

Geology.—The influence of the rocky substratum upon the character of the scenery and soil is clearly marked. It is sufficient to point, on the one hand, to the dry chalky upland of the Chiltern Hills and the oolitic limestone hills in the north-west, or the Cornbrash with its rich, fertile soil; and, on the other hand, to the dreary scenery of the 0, ford Clay land with its cold, unproductive soil. Cretaceous rocks occupy the south-eastern corner of the county; Jurassic rocks prevail over the remainder. The general dip is towards the south-east, and the strike of the strata is S.W.-N.E.; therefore in passing from south to north, beds are traversed which are successively lower and older. The Chiltern Hills, with a strong scarp facing the north-west, are formed of Chalk, the Lower Chalk at the foot and the hard Chalk rock at the summit; from the top of the hills the Upper Chalk-with-Flints descends steadily towards the Thames. Here and there, as at Shiplake and Nettlebed, outliers of Tertiary clays rest upon it. The Upper Greensand forms a low feature at the foot of the Chalk hills; this is succeeded by the Gault, with an outcrop varying from 4 m. to 1 m. wide between Dorchester and Sydenham; it is a pale blue clay, dug for bricks at Culham. The Lower Greensand appears from beneath the Gault at Culham and Nuneham Courtney and in outliers north of Cuddesdon. The Kimmeridge clay, in the grass-covered vales between Sandford and Waterperry, is separated from the Lower Greens and by the Portland limestone and Portland sands and by the thin Purbeck beds; it is dug for bricks at Headington. Both Portland and Purbeck beds may be observed in Shotover hill; the Portland limestone is quarried at Garsington. The Coral Rag, with calcareous grit at the base, is a shelly, coral-bearing limestone, traceable from Sandford to Wheatley; it has been extensively quarried at Headington hill. North-west of the last-named formation a broad outcrop of Oxford Clay crosses the county; while this is mostly under pasture, the next lower formation, the Cornbrash, a brownish rubbly limestone, gives rise to a loose brown soil very suitable for the cultivation of wheat. Exposures of Cornbrash occur at Norton