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Rh him precedence next to the dukes. He was declared of legitimate birth, and in 1455 the royal favour found him a wife in the Lady Margaret, daughter of John Beaufort, duke of Somerset. But he died the next year, and his only child, afterwards Henry VII., was born on the 28th of January 1456/7, three months after his death.

Edmund's younger brother, Jasper Tudor, survived him many years. Jasper was knighted in 1449 and, about the date of Edmund's patent, was created earl of Pembroke. He bore the royal arms of France and England, differences with a blue border charged with the royal martlets of the Confessor's fabulous shield, and the same was formerly to be seen upon his Garter stall-plate of 1459. He fought at St Albans in 1455 for the king who had advanced him, and two years later we find him strengthening the defences of Tenby. In 1460 he seized and took Denbigh, where the queen joined him after Northampton. He shared the defeat in 1461 at Mortimer's Cross, where his father the Welsh squire was taken and beheaded, and left the country in 1462. In 1465 he made a last descent upon Wales, to be driven off by William Herbert, who was rewarded with his earldom of Pembroke, already forfeited by attainder. But he was an obstinate and loyal partisan. He came back again with Warwick in 1470 and was hurrying to join the queen when Tewkesbury was fought and lost. After many adventures he carried off his young nephew Richmond to Brittany. The two came back together in 1485. After Bosworth, Jasper was created duke of Bedford and restored to his earldom, the earl-marshalship being given him in 1492. He lived to fight at Stoke in 1487 against Lincoln and Simnel his puppet and to be one of the leaders of the host that landed in France in 1492. He died in 1495 leaving no issue by his wife Catherine, the widow of the second duke of Buckingham and a daughter of Richard Widvile, Earl Rivers. But his bastard daughter Ellen is said to have been mother of Stephen Gardiner, bishop of Winchester.

TUDOR FLOWER, or, an architectural ornament much used in the Tudor period on the tops of the cornices of screen work, &c., instead of battlements. It consists generally of a flat, upright leaf standing on stems.

TUDOR PERIOD, in architecture, the later development of medieval architecture which followed the Perpendicular and, although superseded by the Elizabethan and the Renaissance styles, still retained its hold on English taste, portions of the additions to the various colleges of Oxford and Cambridge being still carried out in the Tudor style down to the middle of the 18th century. In church architecture the principal examples are Henry VII.'s Chapel at Westminster (1503), King's College Chapel, Cambridge, and St George's Chapel, Windsor; and the old schools at Oxford; and in domestic work, Eltham Palace, Kent; Oxburgh Hall, Norfolk; King's College, Aberdeen; Layer Marney Hall, Essex; the manor house at East Barsham, Norfolk; and Ford's Hospital, Coventry. It was a further debasement of the Perpendicular style, and the four-centred arch was its principal feature; some of the most remarkable examples of the bow-window belong to this period; the mouldings are more spread out and the foliage becomes more natural.

 TUFF (Ital. tufo), a rock consisting of volcanic ashes, the ejectamenta of craters in a state of eruption. The products of a volcanic eruption may be classified into three groups: (a) steam and other gases, (b) lavas, (c) ashes. The ashes have not been burnt in any way though they resemble cinders in appearance: they are merely porous, slaggy pieces of lava which have been tossed into the air by outbursts of steam and have become vesicular by the expansion of the gases within them while they were still plastic.

Among the loose beds of ash which cover the slopes of many volcanoes, three classes of materials are represented. In addition to true ashes (a) of the kind above described, there are lumps of the old lavas and tuffs (b) forming the walls of the crater, &c., and which have been torn away by the violent outbursts of steam, pieces of sedimentary rocks (c) from the deeper parts of the volcano, which were dislodged by the rising lava, and are often intensely baked and recrystallized by the heat to which they have been subjected. In some great volcanic explosions nothing but materials of the second kind were emitted, as at Bandaisan in Japan in 1888. There have been many eruptions also at which the quantity of broken sedimentary rocks mingled with the ashes is very great; as instances we may cite the volcanoes of the Eifel and the Devonian tuffs, known as “ Schalsteins," in Germany. In the Scotch coalfields some old volcanoes are plugged with masses consisting entirely of sedimentary débris: in such a case we must suppose that no lava was ejected, but the cause of the eruption was the sudden liberation and expansion of a large quantity of steam. These accessory or adventitious materials, however, as distinguished from the true ashes, tend to occur in angular fragments; and when they form a large part of the mass the rock is more properly a “ volcanic breccia ” than a tuff. The ashes vary in size from large blocks twenty feet or more in diameter to the minutest impalpable dust. The large masses are called “ bombs ”; they have mostly a rounded, elliptical or pear-shaped form, owing to rotation in the air while they were still viscous. Many of them have ribbed or nodular surfaces, and sometimes (at Volcano and Mont Pelé) they have a crust intersected by many cracks like the surface of a loaf of bread. Any ash in which they are very abundant is called an agglomerate (q.v.).

In those layers and beds of tuff which have been spread out over considerable tracts of country and which are most frequently encountered among the sedimentary rocks, smaller fragments preponderate greatly and bombs more than a few inches in diameter may be absent altogether. A tuff of recent origin is generally loose and incoherent, but the older tuffs have been, in most cases, cemented together by pressure and the action of infiltrating water, making rocks which, while not very hard, are strong enough to be extensively used for building purposes (e.g. in the neighbourhood of Rome). If they have accumulated sub aerially, like the ash beds found on Etna or Vesuvius at the present day, tuffs consist almost wholly of volcanic materials of different degrees of fineness with pieces of wood and vegetable matter, land shells, &c. But many volcanoes stand near the sea, and the ashes cast out by them are mingled with the sediments that are gathering at the bottom of the waters. In this way ashy muds or sands or even in some cases ashy limestones are being formed. As a matter of fact most of the tuffs found in the older formations contain admixtures of clay, sand, and sometimes fossil shells, which prove that they were beds spread out under water. During some volcanic eruptions a layer of ashes several feet in thickness is deposited over a considerable district, but such beds thin out rapidly as the distance from the crater increases, and ash deposits covering many square miles are usually very thin. The showers of ashes often follow one another after longer or shorter intervals, and hence thick masses of tuff, whether of subaerial or of marine origin, have mostly a stratified character. The coarsest materials or agglomerates show this least distinctly; in the fine beds it is often developed in great perfection.

Apart from adventitious material, such as fragments of the older rocks, pieces of trees, &c., the contents of an ash deposit may be described as consisting of more or less crystalline igneous rocks. If the lava within the crater has been at such a temperature that solidification has commenced, crystals are usually present. They may be of considerable size like the grey, rounded leucite crystals found on the sides of Vesuvius. Many of these are very perfect and rich in faces, because they grew in a medium which was liquid and not very viscous. Good crystals of augite and olivine are also to be obtained in the ash beds of Vesuvius and of many other volcanoes, ancient and modern. Blocks of these crystalline minerals (anorthite, olivine, augite and hornblende) are common objects in the tuffs of many of the West Indian volcanoes. Where crystals are very abundant the ashes are called “ crystal tuffs.” In St Vincent and Martinique in 1902 much of the dust was composed of minute crystals enclosed in thin films of glass, because the lava at the moment of eruption had very nearly solidified as a crystalline mass. Some basaltic volcanoes, on the other hand, have ejected great quantities of