The ogee arch is frequently used in small arcades and in the heads of windows. The dripstones, or hood moulds, are generally supported by heads and are frequently enriched with crockets and finials. The arcades that ornament the walls and those over the _sedilia_ are characteristic features of the style. Pillars are clustered and arches richly moulded; they often have the hood-moulding over them. Very often they have what is called a stilted base. The capitals are ornamented with beautiful foliage: each leaf is copied from nature and often arranged round the bell of the capital. The ornamental sculptures in the hollow mouldings are numerous, but there are two which require more particular notice; they are nearly as characteristic of the Decorated style as the zigzag is of the Norman, or the tooth-ornament of the Early English. The first is the ball-flower, which is a globular flower half opened, and showing within a small round ball. It is used with the utmost profusion in the mouldings of windows, doorways, canopies, cornices, arches, etc. The other ornament is the four-leaved flower. This has a raised centre, and four petals cut in high relief; it is frequently much varied, but may be distinguished by its being cut distinctly into four petals, and by its boldness: it is sometimes used abundantly, though not quite so profusely as the ball-flower. In some instances the centre is sunk instead of being raised. The battlement, as an ornamental feature in the interior of buildings, is frequently used in this style, although it is more common in the Perpendicular. The foliage in this style is more faithfully copied from nature than in any other: the vine-leaf, the maple and the oak with the acorn, are the most usual. The surface of the wall is often covered with flat foliage, arranged in small squares called diaper-work, which is believed to have originated in an imitation of the rich hangings then in general use, and which bore the same name. The groined roofs or vaults are distinguished from those of the preceding style, chiefly by an additional number of ribs, and by the natural foliage on the bosses. Many fine examples of these remain, as in the Cathedral of Exeter and at York in the chapter-house; at Norwich in the cloisters; at Chester the vault is of wood with stone springers. After culminating in the Decorated style, Gothic Architecture began to decline in the Fifteenth and Sixteenth Centuries. The transition from the Decorated to the Perpendicular took place from 1360 to 1399: