FOUR-PART. A four-part vault is a groined vault formed by the intersection of two barrel vaults. Its diagonal edges or _groins_ divide it into four sections, triangular in plan, each called a _compartment_. GIGANTOMACHIA, a group or composition representing the mythical combat between the gods and the giants. HALF-TIMBERED, constructed with a timber framework showing externally, and filled in with masonry or brickwork. IMAUM, imâm, a Mohammedan priest. KAABAH, the sacred shrine at Meccah, a nearly cubical structure hung with black cloth. KARAFAH, a region in Cairo containing the so-called tombs of the Khalifs. LACONICUM, the sweat-room in a Roman bath; usually of domical design in the larger thermæ. MEZZANINE, a low, intermediate story. MUEDDIN, a Mohammedan mosque-official who calls to prayer. NARTHEX, a porch or vestibule running across the front of a basilica or church. NEO-GOTHIC, NEO-MEDIÆVAL, in a style which seeks to revive and adapt or apply to modern uses the forms of the Middle Ages. OCULUS, a circular opening, especially in the crown of a dome. OGEE ARCH, one composed of two juxtaposed S-shaped or wavy curves, meeting in a point at the top. PALÆSTRA, an establishment among the ancient Greeks for physical training. PAVILION (Fr. _pavillon_), ordinarily a light open structure of ornate design. As applied to architectural composition, a projecting section of a façade, usually rectangular in plan, and having its own distinct mass of roof. QUARRY ORNAMENT, any ornament covering a surface with two series of reticulated lines enclosing approximately quadrangular spaces or meshes. QUATREFOIL, with four leaves or _foils_; composed of four arcs of circles meeting in cusps pointing inward. QUOINS, slightly projecting blocks of stone, alternately long and short, decorating or strengthening a corner or angle of a façade. REVETMENT, a veneering or sheathing. RUSTICATION, treatment of the masonry with blocks having roughly broken faces, or with deeply grooved or bevelled joints. SOFFIT, the under-side of an architrave, beam, arch, or corona. SPANDRIL, the triangular wall-space between two contiguous arches. SQUINCH, a bit of conical vaulting filling in the angles of a square so as to provide an octagonal or circular base for a dome or lantern. STOA, an open colonnade for public resort. TEPIDARIUM, the hot-water hall or chamber of a Roman bath. TYMPANUM, the flat space comprised between the horizontal and raking cornices of a pediment, or between a lintel and the arch over it. VOUSSOIR, any one of the radial stones composing an arch. INDEX OF ARCHITECTS. The _surname_ is in all cases followed by a comma. Abadie, 373 Adams, Robert 234 Agnolo, Baccio d’ 291 Agnolo, Gabriele d’ 287 Alberti, Leo Battista 277, 280 Alessi, Galeazzo 299, 302 Ammanati, Bartolomeo 300 Anselm, Prior 219 Anthemius of Tralles, 127 Antonio, Master 259 Arnold, Master 243 Arnolfo di Cambio, 162, 265