Architectural Elements of Churches, Prothyron

Descoeudres, G. Die Pastophorien im syro-byzantinischen Osten. Wiesbaden, 1983. Graf, G. Verzeichnis arabischer kirchlicher Termini, p. 89. Louvain, 1954. PETER GROSSMANN Prothyron A prothyron is an open porch supported by two columns in front of the outer doors of a church or other building. It is thus a diminutive propylaeum or a portico reduced to a single bay (see "porch," above). The roof, which is fixed to the building wall, may be a small dome or a saddleback, and the columns are connected to each other and the wall by architraves or arches. The prothyron is generally raised at least one step from the ground. The prothyron was often used in classical times (Vitruvius 6.7) but was more commonly used in Byzantine churches. Examples in Egypt are rare and occur almost solely along the coast, especially in the vicinity of Alexandria. The Great Basilica at Abu Mina has prothyra placed inside (Schläger, 1965, ill. 1), but these lead to side rooms and chapels that can only be entered from the church. The prothyron also found its way into Islamic architecture and occurs repeatedly, in particular in the buildings of the sixteenth-century Turkish architect Mi’mar Sinan (Egli, 1976). In modern Coptic architecture the porch corresponds to it. BIBLIOGRAPHY Egli, E. Sinan, der Baumeister osmanischer Glanzzeit. Stuttgart, 1976. Kaufmann, C. M. Handbuch der christlichen Archäologie, p. 183. Paderborn, 1913. Schläger, H. "Abu Mena Zweiter Vorläufiger Bericut." Mitteilungen des Deutschen Archäologischen Instituts—Abteilung Kairo (1965):122-25. PETER GROSSMANN Return aisle A return aisle is a passage at the western end of a church that is a unique feature of the early Christian basilica in Egypt. It is spatially related to the nave in the same way that the long north and south aisles are (although its width may vary) and is connected to them without restriction by lateral buttresses or engaged pillars and columns. It is therefore fundamentally different from the internal narthex, which faces the inside of the church and is usually separated from the nave area by lateral buttresses. The return aisle probably owes its origin to the need to find room for a bridge passage to connect the galleries over the long aisles. In this regard, a single staircase was sufficient. Thus, the return aisle is first of all an element in churches with galleries. Typologically, however, it seems to have been anticipated in some subterranean tomb complexes by an ambulatory, deriving from pagan times. In Egyptian church building it became a requirement in the first half of the fifth century at the latest, for from this period on, it can be found even in churches that certainly never had a gallery. In the medieval Egyptian basilica it gradually fell out of use, but it is still found in several eighth-century churches. BIBLIOGRAPHY Grossmann, P. "Zur christlichen Baukunst in Ägypten." Enchoria Suppl. 8 (1978):89f. Monneret de Villard, U. Les Couvents près de Sohâg, Vol. 2, p. 95. Milan, 1926. ______. "La basilica cristiana in Egitto." In Atti del IV congresso internazionale di archeologia cristiana, Vol. 1, p. 313. Vatican City, 1940. PETER GROSSMANN Roof A roof is the top covering of a building and its supporting frame. It may be flat, saddleback (pitched), or vaulted. In Egypt since earliest times, the flat roof was preferred. Probably from the Hellenistic period, saddleback roofs were used only for buildings that had an unusually wide span, such as classical temple complexes, market buildings, and especially churches. Stone vaults were rare and were used only in areas where wood for roof beams and frames was not available. Even the earliest sepulchers, however, were built of lasting materials. Churches from the Fatimid period on used vaulting because it was less liable to be damaged by worms or fire, a change specifically mentioned in the sources. The construction of a flat roof was essentially that of a ceiling (see above). It required additional precautions, however, to ensure the trouble-free draining of rainfall. The surface was strengthened with a layer of stones or bricks that were then completely covered by a coat of plaster, in order to seal all openings. To make it more solid, the plaster was often enriched with chips of burnt brick, producing a weatherproof mortar akin to opus signium developed in the Roman period. Roof tiles were not known in Egypt. Since the upper edges of a building can be easily damaged by wind and rain, the edges of the roof were always provided with at least a low wall. Higher buildings required a parapet. The surface of the roof was given either a slope or separate water channels, which let rain water flow into gutters at the edge of the roof. Two drainage systems were in use in the pharaonic period. In large, high buildings, waterspouts projecting clear of the wall surfaces were employed, as at Dayr Anba Shinudah, which prevented the wind from splashing the water against the walls. In smaller buildings, including such pharaonic temples as that of