In large and lofty halls, stone arches were thrown across and, on these, either flat or laid to a pitch, rested the wooden covering.
In this way a broad span was accomplished in a manner both impressive and economical.
This was an ancient Asiatic system, perhaps Syrian in origin, which was much used in northern Italy and in Provence during the Middle Ages.
The type abounds in the provinces of Galicia, Estremadura, Catalonia, and Valencia (the last mentioned once a part of Catalonia).
In Catalonia, where churches and civic buildings are remarkable for their extraordinary span, it was especially appropriate, as the walls were well bonded by the transverse arches.
Where the roof was ridged in form, its decorated underside often served for the ceiling, as in the church of Santa Agiieda, Barcelona.
In other cases the actual roof construction was distinct and the exposed ceiling flat, as seen in the Lonja, Barcelona This latter is set out in an unusual manner. The hall is of great width and, instead of the typical transverse arches, it is divided longitudinally into three naves by two rows of arcading supported on lofty piers.
In all these old arch-supported ceilings, the corbels are either of stone or wood, carved in one piece and passing directly through the stone arch, thus rendering it unnecessary to embed the beam- ends — a method which leads to dry-rot.
For additional security, however, the beam-ends are clamped together by long iron dogs. In a hall long enough to permit of a succession of transverse arches, a noble ceiling results, whether decorated or not, as may be seen in the famous long dormitory of the monastery of Poblet.
Among examples with stone arches there is one instance where the arches themselves are profusely painted — the ancient sola capitular or chapter-room of the monastery of Sigena in Aragon.
The beamed ceiling is more intimately seen in domestic work, where a few refinements were indulged in, both constructive and decorative, which would have been entirely lost on a work of larger scale.
It seems a general rule that the smaller the room the greater the depth of the ceiling treatment.
The Concealed Beam Type: Setting aside for the moment the Renaissance coffered ceiling, which structurally was of this type, and analyzing only the Mudejar product, it will be seen that the latter was nothing more than the nailing of boards to the underside of the beams either at right angles or diagonally.
Moldings were then applied in a pattern of geometric figures or interfacings, and in the small spaces or shallow coffers thus created, were nailed rosettes, pendants, shields, etc.; or, as was often the case, the flat panel was left to the painter to decorate.
The whole fabrication was simplicity itself, and the diversity of ornamentation very great, as a glance at the illustration will show (Fig. I).
Where this type of ceiling covered a large area it was often braced by diagonal struts at the wall. These in turn were similarly boarded over, creating a covering which was three-plane in section.
Ceilings are distinct structurally, it will be seen, from the three-plane peaked ceiling to be described presently.
The Peaked Type: For domestic work, the Mudeiar ceiling offering most inspiration to the modern architect is this of open rafter construction (Fig. 10).
Primarily, it is as easy to build as our own open timber ceiling and has, moreover, certain points of superiority.
First, by truncating the crown of the ridge, a pleasanter and more domestic-looking form is created; second, by coupling up the hip-rafter
greater interest is secured than by the use of our single hip-rafter; moreover, additional interest is imparted by featuring the tie or collar-beams and supporting them on carved corbels.
These are often the only decorated item.
The Vaulted Type: The richest and most exaggerated expression of Moorish carpentry is found in vaulted, domical or media naranja, and polygonal ceilings.
Palaces, otherwise intact, have lost the lofty wooden dome over the stair-well and can show nothing but a flat modern boarding. This is unfortunately the case in even so carefully a preserved home as the Alba Palace in Seville.
Over square rooms where height would permit, a variation of the dome is found in the shape of the lofty eight-sided ceiling. The octagon is created by canting the corners, and the sides are projected upward toward a common point until they intersect a truncating panel.
The result might be described as a polygonal dome. The exposed peak whether in a square or oblong room, was always distasteful to the Spanish ceiling-maker and the improvement secured by truncating justifies his aversion.
To what extent the top panel could be developed, decoratively, may be seen in the charming ceiling of San Pedro in Cuenca.