The construction methods used by the Franks combined Western techniques brought to the East by the new settlers with techniques which they encountered in the East. The manner in which they applied Western or Eastern methods depended on the type of building they were constructing. In churches the Franks followed Western traditions with only limited use of Eastern building practices, such as the use of flat rather than gabled roofs and pointed arches. In urban domestic architecture, although Eastern layout was commonly adopted, there was restricted use of local construction methods and decorative elements such as interlocked or joggled voussoirs in arches and ablaq (alternating use of dark and light-coloured stone which is occasionally found in Frankish buildings but became popular in Mamluk architecture). In newly founded villages there is little that can be said to be local or Eastern. The masonry of all types of buildings was carried out by the methods in use in western Europe: fine diagonal tooling together with widespread use of masons’ marks (Plates 8.1 and 8.2). The combination of fieldstone construction with drafted quoins, window frames and door frames is another technique not found in local architecture prior to the twelfth century.
Mortar and plaster
The mortar used in Frankish buildings varies in quality, from the coarse mud mortar used for the core of rubble-filled walls of domestic buildings to the hard white mortar found in fine masonry and the extremely hard mortar used in fortifications. The latter is so hard that in sandstone construction such as the walls of Ascalon and Caesarea it remains solid long after the ashlar facings have worn away, and at Vadum Jacob, where the ashlars have been robbed, the core still stands to a height of six or seven metres.
Plaster was made from lime and sand mixed with water with occasional carbonized organic material. Potsherds were added to hydraulic plaster that lined cisterns. Plaster was generally applied in at least two layers, the uppermost one being smoother and finer. ‘Fish scale’ or ‘herringbone’ trowel incisions were often applied to give the surfaces a better grip. Plaster was occasionally used in a decorative manner by moulding, incision, painting or a combination of these. Church walls and ceilings were sometimes decorated with frescos, but in general
Plaster was used in a purely functional manner and the remarkable use of stucco ornamentation found in Islamic buildings is unknown.
Wood
Apart from the scaffolding used in the construction of vaults, there was only limited use of wood in Frankish buildings. Evidence of scaffolding for barrel vaults can be seen in the presence of putlog holes. These are holes in the side walls, at the base or spring of the vault, into which the wooden frame was placed. Window frames and shutters and door panels were certainly made of wood but have not survived. Staircases were occasionally wooden; at Chastel Rouge a wooden staircase originally led to the first-floor doorway. In a Frankish building at Akhziv (Chastel Imbert) a wooden staircase gave access to an opening high in one of the walls, from where a stone staircase continued inside the thickness of the wall. In castles and city gates there were wooden drawbridges, and towers had wooden hoardings, but only the stone supports have survived.
Stone
Whereas in the northern principalities there was a reasonably good supply of timber for construction, in the kingdom of Jerusalem there were few forests and the native trees were small and of little use in construction. Building stone, however, was plentiful throughout the Latin East and was in any case better suited to the climate, retaining the cool night temperatures well into the heat of the day. Various types of stone were available in different regions. In the hilly interior there were different qualities of limestone, including a soft and inferior building stone known locally as nari as well as harder lime-stone. In the eastern highlands volcanic basalt was available. A hard stone to work, it was generally used for fieldstone construction and was occasionally combined with limestone to achieve a decorative quality perhaps best seen at Margat Castle. The Levantine coast is lined with a double ridge of cross-bedded, wind-laid calcareous sandstone known locally as kurkar (eolianite), which is formed from deposits of Nile sands. Kurkar has always served as the principal building material in the coastal cities.
Stone was generally quarried on or very near to the construction site. In some buildings a finer-quality stone was brought in from more distant quarries for use in decorative elements. In many sites marble or granite spolia from ancient buildings were available and these were used for both decorative and functional construction. The Frankish adage that a castle destroyed is a castle half built finds testimony in many of their buildings. In the Land Castle at Sidon the ancient vomitoria of the Roman theatre formed the base of the castle, at Beit She’an and Beit Govrin amphitheatre seats were reused in the castle walls, and a Roman sarcophagus was built into the walls of the tower at Saffuriya. At
Ascalon and Caesarea granite and marble columns were reused as lateral ties in the fortification walls.
A number of quarries have been identified and surveyed over the years at sites including Montfort and Destroit, and most recently at Nebi Samwil, Vadum Jacob and Blanchegarde.1 The quarrying technique that can be observed in these quarries appears to differ little from that of earlier periods. With the use of hammers and iron chisels the stone was cut into cubes and then tooled on the quarry site. To facilitate the process of freeing the stone, quarries were often located at sites where a limestone bed only about one metre thick lay on a harder layer of basalt or a softer layer of chalk. Vertical V-shaped channels were cut through the limestone down to the level of the harder or softer stone, from which it could be pried free with relative ease. This technique can clearly be seen at Vadum Jacob, where the limestone bed lies on basalt, and at Blanchegarde, where soft chalk is located under the harder limestone.
Treatment of the stone
Once it was freed from its surroundings, the ashlar was shaped by the mason and then carefully tooled to give it a smooth finish (Plate 8.1). Ellenblum noted that this often took place in the quarry rather than at the building site, and worked stones are occasionally found on quarry sites. The quality of the tooling varied with the type of building under construction. In the case of fortification walls and rural domestic buildings the tooling was generally fairly coarse, whereas in churches and urban public and domestic buildings the workmanship was usually very fine. The Franks introduced to the East a method of dressing stone with fine diagonal striations, particularly common from the thirteenth century on in France and England (Braun 1968:65). Clermont-Ganneau was the first to recognize its use in the East, identify it as a characteristic of Frankish construction and consequently realize its value as a means of identifying Frankish buildings (Clermont-Ganneau 1899:40).
In the doorway of the now destroyed farmhouse at Har Hozevim, Jerusalem, a number of unfinished stones displayed this surface treatment. From these examples we can see the stages of the tooling process. The stone was first roughly smoothed with a tool which left round impressions about 4 mm wide and 2 cm long and 2-3 cm apart. Subsequently similar but finer tooling was carried out, leaving impressions 3 mm wide and 1 cm long and spaced about 3 mm apart. In the final stage a serrated tool was applied to the surface leaving impressions of about 2.5-3 cm long but carried out consecutively, so that they appear as continual diagonal lines.
Other techniques frequently used by Frankish masons involved tooling of the entire surface of the stone except for the margins of the face (usually about 10 cm wide), and in other cases tooling only the margins and leaving the remainder of the stone unworked as a rough, pronounced boss. The use of marginally tooled stones is not limited to the medieval period, but the Franks do seem to have been
Plate 8.1 Frankish stonework: diagonal tooling (photograph by the author)
Responsible for cases where it is restricted to the quoins, window frames and door frames, with the remainder of the construction being of roughly worked fieldstone (Ellenblum 1992:72).
Masons’ marks
Letters and symbols are frequently found incised on the surface of worked stones in Frankish buildings (Plate 8.2). Various interpretations have been suggested for the function of these marks, including the possibility that they were quality
Plate 8.2 Frankish stonework: masons’ marks (photograph by the author)
Marks made by masons accepting responsibility for the accuracy of stones they had hewn (Braun 1968:64), or that they were assembly marks labelling stones prepared at distant quarries for positioning in a building (Ellenblum forthcoming). In most cases, however, they appear simply to have been the tallies of individual masons that enabled them to identify and count the stones they had cut in a certain period in order to receive payment for their labour. The use of masons’ marks in Frankish buildings was first recorded in 1669 by the Franciscan Father Morone da Maleo (da Maleo 1669: 209).2 Their importance in identifying Frankish construction was once again first noticed by Clermont-Ganneau (1899:1-38).
Construction
In roof construction the Franks generally adopted the flat roofs that are typical of Eastern architecture. This is true even of buildings which in other aspects were typically Western, such as churches. There is, however, occasional evidence for the use of gabled tiled roofs. We find them in a building constructed by the Ternplars beside the Templum Domini in Jerusalem which Theoderich described as having a high-pitched roof, contrary to the local custom (Theoderich 1891: 31). Roof-tiles have occasionally been found in Frankish buildings such as at the farmhouse at Har Hozevim near Jerusalem. Here, as in earlier periods, large, flat, rectangular tiles with raised edges (tegulae) were used together with narrower, arched riders (imbrices). The tiles were set in place and sealed with plaster.
Domed roofs are unusual in Frankish buildings except for occasional use in churches, where the transept crosses the nave, and in small constructions such as ovens. For roof construction, both in domestic and in monumental buildings, the Franks generally employed vaults. They adopted the slightly pointed Eastern arch before it became popular in Western Gothic architecture; it became one of the distinguishing features of Romanesque architecture in the Latin East, while in Western Romanesque arches and vaults remained rounded. The Franks used both groin vaults (cross vaults) and barrel vaults (tunnel vaults). The barrel vault, which has been described as ‘a continuous arch resting on the side walls of a building’ (Mitchell and Mitchell 1908:292), was used to cover rectangular spaces. It was comparatively easy to construct but had some disadvantages: it was limited to a certain width, about 7 m, and the side walls had to be extremely thick in order to support the weight and downward thrust of the superstructure. This necessitated limiting or avoiding altogether the opening of doors and windows in the side walls. Consequently, this type of construction was preferred for cellars or ground floors but not for upper storeys. In order to construct a barrel vault, continuous, half-wheel-shaped wooden frames were inserted into the upper part of the side walls on to which a wooden vault was constructed. On this the stone vault was built, and after its completion the framing was removed and the holes made in the side walls to support the framework (putlog holes) were blocked.
In the excavation of the farmhouse at Har Hozevim in Jerusalem it was possible to examine the make-up of a typical barrel vault. A cross-section of the collapsed main vault was exposed. It contained seven distinct layers: a grey plaster which covers the interior of the vault, a layer of large, roughly shaped, vertically placed stones which was bonded with the same grey mortar, a fill of terra rossa and fieldstone, a layer of yellowish, sandy gravel, a thin layer of terra rossa, a second thin, yellowish, sand layer, and finally a layer of grey plaster which apparently formed the floor of the upper storey.
With the groin vault the thrust was concentrated on the piers; this meant that, unlike with barrel vaults, the walls could have large openings on all sides. Groin vaults were usually constructed of brick-shaped stones of varying size set in mortar and covered with plaster. In addition to its attractive appearance, the advantage of the groin vault lies in the fact that the limitation to its dimensions could be overcome by using several connected groin-vaulted bays supported on piers. In Gothic architecture the rib-vault was often used; it is so-called because the arris (the meeting apex of two vault planes) is projected in a rib-like form (Plate 8.3). The ribs were often supported on small ‘elbow’ columns that extend out from a wall and immediately bend at a right angle, supporting a small capital which in turn supports the rib of the vault. At the junction of the ribs at the centre of the vault there was often an elaborately carved keystone bosset.
Another means of roofing occasionally employed by the Franks was a flat wooden roof supported on stone transverse arches. This was easier to construct
Plate 8.3 Rib-vaulting in Crac des Chevaliers (photograph by Jonathan Phillips)
Than stone vaulting but had neither the strength of the barrel vault nor the beauty of the groin vault, and its construction was dependent on the availability of timber. More often transverse arches were used to strengthen barrel vaults and to support the divisions between naves and aisles in churches or between bays in groin-vaulted halls.
The construction of walls in Frankish buildings, particularly the side walls of barrel vaults, was carried out by building an outer and an inner wall of solid ashlar masonry (or alternatively of fieldstone with marginally drafted quoins) and then filling the space between the two walls with rubble andmud mortar. Floors in public buildings were often constructed of well-cut pavers. In much
Plate 8.4 Moulded arch on the door of St Anne’s Church, Jerusalem (photograph by Yael Sternheim)
Private architecture, however, floors were of either packed earth or lime, or if the building was constructed directly on the bedrock the builder simply worked the rock to a reasonably smooth finish and occasionally covered it with a lime surface.
In Frankish architecture doors and windows have both rounded and pointed arches or have a flat lintel. Occasionally there is use of interlocked or joggled voussoirs, a technique which gained great popularity in Mamluk architecture. Shallow relieving arches were frequently used to take the weight off monolithic stone lintels. Embrasure windows are characteristic of both public and private buildings, as are double windows. The use of mouldings (hood mouldings or drip mouldings over doors and windows, cornice mouldings and mouldings on imposts) was a popular means of accentuating the architectural form (Plate 8.4). As in the West, windows may have been covered by wooden shutters or oiled leather, but certainly glass was also used. Fragments of plate glass are occasionally found and circular panes of blown glass about 20 cm in diameter, generally greenish in colour, were occasionally used (Benvenisti 1970:386). Examples of such panes have been recovered at Beit She’an (see p. 190, n. 10). Doors had wooden panels, usually two, and were supported by an axle which fitted into sockets behind the thresholds and lintels. The sockets were lined with bronze, lead or iron to facilitate the movement of the doors.3 Shallow channels on the thresholds allowed the axle post to be slipped into place; these channels were necessary because the height of the axle post was greater than that of the door. The doors opened inward and could be secured by means of a bolt mechanism and a wooden beam which was drawn out of a channel in the side wall.
Staircases were constructed either of wood, in which case they have not survived, or of stone, and were carried on half-arches. In the kingdom of Jerusalem there is little use of the spiral staircase which is common in the West. In castles, churches and manor houses, staircases were often built within the thickness of walls in order to save space. Cisterns were present in most buildings and deemed a necessity in castles and private dwellings. They were fed from pipes leading from catchment areas such as roofs and paved courtyards. The cisterns were usually barrel-vaulted or, if cut into the bedrock, bell-shaped. They were lined with hydraulic plaster and were often attached to a sump shaft.
Notes
1 Publication of the latter three sites is now under way.
2 Masons’ marks have been discussed by Clermont-Ganneau in some detail. See Clermont-Ganneau 1899:4-38, and for a more up-to-date discussion see Pringle 1981:173-99.
3 At Vadum Jacob lead was found in some of the door sockets.
World History
