, 2nd millennium BC ,
Broadway Tower, England Corbelling, where rows of corbels gradually build a wall out from the vertical, has long been used as a simple kind of
vaulting, for example in many Neolithic
chambered cairns, where walls are gradually corbelled in until the opening can be spanned by a slab. Corbelled vaults are very common in early architecture around the world. Different types may be called the
beehive house (ancient Britain and elsewhere), the Irish
clochán, the pre-Roman
nuraghe of
Sardinia, and the
tholos tombs (or "beehive tombs") of Late
Bronze Age Greece and other parts of the Mediterranean. In
medieval architecture, the technique was used to support upper storeys or a parapet projecting forward from the wall plane, often to form
machicolations (openings between corbels could be used to drop things onto attackers). This later became a decorative feature, without the openings. Corbelling supporting upper stories and particularly supporting projecting corner
turrets subsequently became a characteristic of the
Scottish baronial style. Medieval timber-framed buildings often employ
jettying, where upper stories are
cantilevered out on projecting wooden beams in a similar manner to corbelling. ==Gallery==